Formula 1: Homebuilt for Speed! KITPLANES

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05 Groppo 2015

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May 2015 | Volume 32, Number 5 Flight Review 6 Orso d’Italia: While it’s not exactly a Cub clone, Groppo’s new Trail kit shares some of the same DNA as Piper’s classic. By Paul Bertorelli. Builder Spotlight 14 K R Airplanes—Affordable, Fun Flying: Chino KR Fly-In showcased this sporty, economical airplane. By Dave Prizio. 18 Formula 1: Getting 260 mph out of an O-200 Continental just for fun. By Tom Wilson. 26 split Decision: Building a vertical-split cowl for an RV-7A. 18 By Roger Kellogg. 32 V inyl Graphics: Colorful alternatives to the plain plane. By Eric Stewart. 38 near the Finish Line: When your plane is almost completed, it’s time to shop for insurance. By Shanna Linton and Jennifer Cummins. 40 Where the Rubber Meets the Runway: Understanding gyroplane nosewheels. By Roy Beisswenger. 68 a sk the DAR: Data plate questions, airworthiness certificate errors, complying with service bulletins. By Mel Asberry. Shop Talk 46 maintenance Matters: Spark plugs: A window into how your engine is running. By Dave Prizio. 66 The New Guy: Getting advice from the Internet. By David Boeshaar. 75 Home Shop Machinist: To launch a Light Sport–redux. By Bob Hadley. Shop Tips 56 Easier Panel Wiring: By David Boeshaar. 65 Camera Mounts: Jim Fleischman. Designer’s Notebook 62 Stressing Structure: Algebra and the control system. By David Paule. 78 Wind TunneL: Spring systems. By Barnaby Wainfan. Exploring 6 2 editor’s Log: Where in the world? By Paul Dye. 5 What’s New: Loyd’s Rivet Drill Guide makes rivet removal easy. By KITPLANES® staff. 52 The Dawn Patrol: “Was he packin’ heat?” By Dick Starks. 57 Risky Business: Distractions—stay focused in the air and the hangar. By Sid Mayeux. 60 Checkpoints: Limitations. By Vic Syracuse. Kit Bits 4 Letters 69 lIst of Advertisers 70 builders’ Marketplace 80 Kit StufF: Drawing on experience. By cartoonist Robrucha. 32 On the cover: Groppo Trail over Florida. Photographed by Paul Bertorelli. For subscription information, contact KITPLANES® at 800/622-1065 or visit www.kitplanes.com/cs. KITPLANES May 2015 1 Editor’s log Where in the world? I guess I learned basic navigation back the head. Today’s GPS would appear no if they believed you at all. To be able to in my Boy Scout days. As a young lad, I less than magic to a navigator from the pinpoint your position anywhere on the learned to get from point A to Point B days of sailing vessels—and probably planet with an accuracy of a few feet using a map and my eyes (we’d call to our much-more-recent ancestors is, in fact, magic to anyone born much that pilotage) as well as a compass and steering aircraft across the vast oceans before 1950. counted paces (the equivalent of ded in WW-II. To tell them as they struggled As we build our own airplanes, we reckoning). I moved on to navigating with maps, charts, circular slide rule are faced with numerous choices. If we via roadmap, nautical chart, and aero- and sextant that all you need to do is winnow away the choice of airframe nautical chart soon after that, always press a button and follow the magenta and engine, the third major expense for remembering that if you knew where line—they’d consider you to be Merlin many is the instrument panel and avi- you started and how you had moved, onics. When it comes to navigational then you must know where you are. information, we have numerous options Aeronautical navigation has pro- ranging from that old-fashioned pilotage gressed in much the same fashion since (looking out the window) to VORs, NDBs, the days of the Wright brothers. From and—yes—the magical box known as looking out the windshield (if there was GPS. For a historically brief time, we could one) to see familiar landmarks, to trust- choose a LORAN receiver, but alas, that ing compass-watch-airspeed, to using has gone the way of the low-frequency fancy electronic aids—aviation naviga- range, airway lights, and the rapidly tion has always trended toward more dwindling number of non-directional precision, quicker navigational solu- beacons. But given that GPS receivers tions, and more reliability. are practically being given away in cereal Homebuilt aircraft have the same nav- boxes (take a look at your cellular tele- igation needs as their certified brethren. phone—it probably can tell you exactly Depending on the mission, the needs where you are right now!), we have to might be more or less complex, but reli- ask the question, “Why would you install ably knowing one’s position relative to a anything else?” departure point or destination is always It’s a good question—and one being the goal. Even when we leave the atmo- answered by many pilots today with a sphere and navigate in outer space, our shrug and a hearty “I wouldn’t!” A lot navigational needs boil down to that depends on how you are going to use same thing—figuring out where in the your airplane, of course. A day-VFR flight world (or the universe) you really are. requires little more than looking out Follow the magenta line—Imagine We are living in a magical time. Arthur telling pilots from long ago that instead that window. But for the modest price of C. Clarke once said that “Any sufficiently of struggling with maps, charts, circular a handheld GPS, you can reliably tell the advanced technology is indistinguish- slide rule or sextant, navigation in the world that you are “7.7 miles southeast able from magic,” and relative to navi- 21st century is as easy as pressing a but- of the field” on your inbound radio call. gational technology, he hit the nail on ton and following a line on a GPS display. If you are flying IFR, you will probably

Paul Dye retired as a Lead Flight Director for NASA’s Human Space Flight program, with 40 years of aerospace experience on everything from Cubs to the space shuttle. An avid homebuilder, he began flying and working on airplanes as a teen, and has experience with a wide range of construction techniques and materials. He flies an RV-8 that he built in 2005, and an RV-3 that Paul Dye he built with his pilot wife. Currently, they are building a Xenos motorglider. A commercially licensed pilot, he has logged over 4800 hours in many different types of aircraft. He consults and collaborates in aerospace operations and flight-testing projects across the country.

2 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes be looking at a certified GPS navigation that “you need to be able to use that So what about backup navigation? box installed in your panel—at least if VOR (or NDB, or low-frequency range!),” For VFR flight, there is always that won- you want to fully utilize the system as it it is hard to beat an actual picture of derful window, a map in your hands (or, works today. ADF approaches are rap- your situation—and modern magic has if you choose, on your iPad). For IFR navi- idly being decommissioned, as are ILS given us that option. gation, it is probably prudent to keep a approaches at many smaller airports. ADS-B and Next Gen are totally reli- VOR receiver for at least a little while GPS overlays with vertical navigation ant on the GPS system—and that is true longer—although I know of pilots who exist for most airports, and the intent whether you are flying a homebuilt or a state that their GPS backup under IFR of the FAA appears to be to change big Boeing. We can argue about if that conditions is radar vectors and a GCA “most” to “all” in very short order. GPS is reckless or not, but the truth is that (ground-controlled approach) at their approaches allow the government to do GPS receivers are extremely reliable, and destination—and believe it or not, an away with expensive and finicky ground the constellation of GPS satellites and argument can be made that this is legal stations and the people who build and their associated ground stations—well, (imagine your com radio being a backup maintain them. they aren’t bomb-proof, but then again, navigational tool!). Let’s not forget that GPS enables neither are VORs or ILS stations. Yes, So, as you lay out that wonderful all sorts of benefits when it comes to the government likes to fiddle around instrument panel, take a look at what cockpit situational awareness, such as with GPS spoofing in the great western is available today and what is coming moving maps and synthetic terrain. For expanses of the United States, but will in the near future before you make those operating in the mountainous they be allowed to do that when Ameri- your choices. Make those choices west, the advantages to modern naviga- can, Southwest, United, and Jet Blue are based on your realistic needs—not tion methods include marvelous safety forced to fully rely on the system for the on old wives’ tales or what used to be enhancements. Knowing where you are safe delivery of the general public to their the norm. Have a reasonable backup relative to, well, anything is information destinations? I think there will be some to make sure you can get down some- that generations of older pilots would serious discussions about that when the where safely, and build the panel that have given anything to understand. public realizes that all of our eggs are in you need, not just what others think No matter how much they might argue that (extremely reliable) basket. you should have. J

Photo: Courtesy of Garmin International, Inc. KITPLANES May 2015 3 EDITORIAL Editor in Chief paul Dye [email protected] Wag-A-Bond needing to consider the aerodynamic Managing Editor mark Schrimmer Ray Hill has built one beautiful air- Art Direction Dan Maher loads for a real analysis. And your sug- Editorial Director paul Bertorelli plane [“Ray Hill’s Wag-A-Bond,” March gestions as to which might be relatively Contributing Editors larry Anglisano, Roy Beisswenger, 2015]. However, the author, Dan Horton important are valid. I deliberately didn’t David Boeshaar, Chuck Berthe, leRoy Cook, Robert Hadley, Dan seems to have gotten carried away with include them since all I wanted to do was Horton, Louise Hose, Ed Kolano, his descriptions. He mentioned that the introduce the concept of the free-body dia- amy Laboda, Dave Martin, Sid airplane has a skylight for steep turns. mayeux, Robert Nuckolls III, gram and show how the Z-brackets carry David Paule, Dave Prizio, Dean Looking at all of the pictures, a skylight the shear load. However, that was beyond sigler, Dick Starks, Eric Stewart, doesn’t show in any of them. I did enjoy the scope of the article. Vic Syracuse, Barnaby Wainfan, Jim Weir, Tom Wilson. reading the article, and it made me want The whole subject of calculating aerody- Web Editor Omar Filipovic one. Ray Hill should be very proud of his namic loads is one that I am not planning Cartoonist Robrucha beautiful little airplane. to get into in the series. All I’m doing is ADVERTISING Richard Warner showing ways to analyze the structure for Sr. Advertising Manager chuck Preston 805/382-3363 those loads once they are there. [email protected] Dan Horton responds: You have a sharp BUSINESS OFFICE eye sir…no skylight in Ray’s Wag-A-Bond. Always Belvoir Media Group, LLC I can only assume my memory was some- With all due respect, the airplane pic- 535 Connecticut Avenue Norwalk, CT 06854-1713 how compromised by the photo plane’s tured on page 52 of the March 2015 skylight (Rans S-7) or my friend’s Leg- edition [“Checkpoints: Fly-In Gems”] EDITORIAL OFFICE 535 Connecticut Avenue end Cub. Until reviewing my photo file, I is not an A-20, but rather an A-26. Norwalk, CT 06854-1713 could have easily passed a polygraph test After the retirement of the Martin 832/851-6665 [email protected] on the matter. B-26, the A-26 was given the B-26 designation. This is how it was known CIRCULATION Circulation Manager Laura McMann Z-Brackets during the Korean War and beyond. David Paule wrote a good article on George Swinford SUBSCRIPTION DEPARTMENT 800/622-1065 Z-brackets [“Stressing Structure,” March www.kitplanes.com/cs 2015], but where is the lift load? He Just wondering if anyone else remem- P.O. Box 8535, Big Sandy, TX 75755-8535 For Canada: Box 7820 STN Main, London, ON N5Y5W1 stated that he ignored the aerodynamic bered Richard Dreyfuss et al. in the loads. I do not know the specifics of movie Always actually flying an A-26 BACK ISSUES P.O. Box 22251 the RV-3B, however, with a very rough Invader rather than an A-20 as men- Beachwood, OH 44122-2251 calculation, given that airfoil lift is con- tioned in the caption and Vic’s text. The 800/571-1555 www.kitplanes.com/backissues centrated near the nose and wing lift , tail feathers, and canopy pro- is concentrated at mid span, I estimate file are clearly that of an Invader; maybe REPRINTS FOR PUBLICATION AND WEB POSTING AVAILABLE that the aerodynamic lift will nearly, just a typo? Minimum Order: 500 if not more than, offset the fuel load. Chip Mauldin Contact Jennifer Jimolka, 203/857-3144 I agree it is customary to ignore some Change of address? minor loads to reduce calculation com- Vic Syracuse responds: My bad. We Missing issue? plexity. However, here I think the aero- Subscription Question? all called it an A-20, and so did Dave dynamic load is the major load. Andrews, but it is registered as a TB-26C, Visit www.kitplanes.com/cs. Daniel MacPherson and in fact is the one in the movie. Google Or call 800/622-1065 from the U.S. and Canada. TB-26C and you will see the actual air- David Paule responds: First off, I want plane N4818E in the Fire Eaters paint job Foreign 903/636-1112 or fax 203/857-3100. to say that you’re entirely correct about and the name “Always” on the nose. J

Back Issues: Call 800/571-1555 Web site Information: General homebuilt aircraft information, back issue availability, online directories ordering info, plus a Kitplanes® article index and selected articles can be found at www.kitplanes.com. Unsolicited manuscripts: are welcome on an exclusive basis, but none can be acknowledged or returned unless accompanied by a stamped, self-addressed envelope. No responsibility is assumed for loss or damage to unsolicited material. Kitplanes® (ISSN 0891-1851) is published monthly by Aviation Publishing Group, LLC, an affiliate of Belvoir Publications, 535 Connecticut Avenue, Norwalk, CT 06854-1713, Robert Englander, Chairman and CEO; Timothy H. Cole, Exec. Vice Pres./ Editorial Director; Philip L. Penny, COO; Greg King, Exec. Vice Pres./Marketing Dir.; Ron Goldberg, CFO; Tom Canfield, Vice Pres., Circulation. Periodicals postage paid at Norwalk, CT, and at additional mailing offices. Copyright ©2015 Aviation Publishing Group, LLC. All rights reserved. Reproduction in whole or in part is strictly prohibited. Printed in USA. Revenue Canada GST Account #128044658. Canada Publishing Agreement #40016479. Subscriptions: One year (12 issues) is $29.95 U.S. $41.95 in U.S. funds in Canada, includes GST. $41.95 in U.S. funds for Foreign Surface Mail or $57.95 in U.S. funds for Foreign Air Mail. Single copy price $4.99 U.S., $5.99 Canadian. POSTMASTER: Please send address changes and subscription inquiries to: Kitplanes®, P.O. Box 8535, Big Sandy, TX 75755-8535, or call 800/622-1065. Kitplanes® is a registered trademark of Aviation Publishing Group, LLC.

4 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes Loyd’s Rivet Drill Guide Rivet Removal? No Problem!

Few airplanes are built that have no sheet metal parts, no matter what their primary construction material. That means that most homebuilders will have to deal with rivets at some point. And if you have to deal with rivets, you will—sooner or later—have to remove some. While flush-head rivets are easily removed using a center punch to start the drill in the right spot, getting started in the center of a round-head (AN470) rivet can present a greater challenge. Technique and experience count a lot in getting the factory head to come off clean, and many builders are frustrated along the way with off-center holes that require up-drilling holes to the next bigger rivet size. Loyd’s Rivet Drill Guide is a kit that will greatly accel- erate the learning process and reduce the frustration. The nicely packaged kit contains a set of cylindrical guides for 3/32-, 1/8-, 5/32-, 3/16-, and ¼-inch rivets, matching drill bits to go with the guides, Boelube lubricant to keep the bit from galling in the guide, and a rugged case to hold all of the parts together. The kits are produced by the Loyd family in Ferris, Texas and are available from Aircraft Spruce & Spe- The kit is packaged in a rugged case with five cylindrical guides, cialty and Aircraft Tool Supply. matching drill bits for each guide, and Boelube lubricant to keep We tested the kit in our own shop after watching the the bits from galling in the guides. video on the company web site and found it to be virtual- in another project. In fact, the only danger we found with ly foolproof. It worked well on AN470-3 and -4 rivets that this tool is that no rivet is safe—we almost started to take we had handy, as well as on some 1/8-inch Cherry rivets set apart an innocent toolbox simply because it had some rivets showing that looked like tempting targets. The guides are easy to use—select the appropriate size cyl- inder and chuck the matching drill into your tool. The guide has a depression machined into the bottom face that fits snugly over the rivet, perfectly centering the drill on the head. Lubri- cate the drill with a dab of Boelube, hold the guide flush to the surface with one hand, and drill with the other—you’ll be through the factory head in no time. Our preferred method of rivet removal is to drill just deep enough to remove the factory head, then to pop the remaining tail from the hole. Others prefer to drill all the way through. Regardless of what works best for you, this tool will get you centered and straight on the rivet head every time. An instructional video is available on the company web site at www.rivetdrillguide.com. The complete set retails for Each guide has a depression machined into the bottom face that fits $129.95 and will be a welcome addition to any shop that has snugly over the rivet, perfectly centering the drill bit on the head. the need to remove round-head rivets. J

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KITPLANES May 2015 5 Orso d’Italia

While it’s not exactly a Cub clone, Groppo’s new Trail kit shares some of the same DNA as Piper’s classic. By Paul Bertorelli

There’s a reason—actually a lot of the basic Cub concept remain a durable export and ship the kit, which I got a reasons—why a Cub looks like a Cub. idea more than 80 years after the first E-2 look at last fall. Any designer (other than Burt Rutan) appeared in a world then still dominated Like the Cub it resembles, the Trail who confronts a clean sheet wanting an by biplanes. The Trail is the work of is a simple airplane, both in systems airplane that’s easy to build, practical to Nando Groppo, an Italian designer who and construction, and is a delight to maintain and flyable with no nasty hab- has been involved in aircraft and compo- fly. Where some LSA designers haven’t its will put the basic strutted high-wing nent design since the 1970s. seemed to pay much attention to how planform on the short list. Whether it’s The Trail—a Rotax-powered tan- the airplane feels and handles, Nando a tandem or side-by-side may be a toss- dem taildragger with the option of Groppo has and it shows. Consistent up, but to look right, the thing ought to a nosegear—has been making the with its European roots, the Trail is also have a tailwheel. rounds of the U.S. shows for about a one of a handful of light aircraft with a And that, in brief, describes why the year. Groppo will offer it as an E/A-B quick wing fold and trailering option. Groppo Trail (www.groppotrail.com) kit, an ELSA and an SLSA, and is just Whether that will prove popular in the looks like it does and why reiterations of now setting up the mechanisms to U.S. is an unknown, but the option is

6 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes (L) Like the Trail, the Dui has folding wings and is designed to be trailered. (R) Nando Groppo broke into aircraft design with ultralights, beginning with the Gropino ultralight. there for builders who want their air- He branched into heavier ultralights are used for towing gliders in . plane to live in the garage next to the with the Dui, whose resemblance to There’s also a float option for those Mercedes. (Alright, the Jeep.) the Trail is unmistakable. Rather than interested in amphibious ops. the Rotax 912 found in the Trail, the History Dui had a Rotax 503 and later an early Construction Nando Groppo has been at the airplane Jabiru powerplant. The Dui had fold- The Trail is designed to be a quickbuild business for a long time. Trained as an ing wings that pivoted into the ver- that requires neither extensive rivet- aeronautical engineer at Italy’s Politec- tical plane chordwise, so it could be ing/metalworking skills nor composite nio di Torino, Groppo worked in the trailered. About 30 of them were com- layup experience. With the exception of aerospace industry through the 1970s pleted in Europe. the provided fiberglass engine cowling, before experimentation with Rogallo The Trail is the latest refinement in wingtips and empennage trim, the air- wings led him to form his own com- Groppo’s line and the most numerous plane is entirely metal. pany. Following the trends of the day, to date. The Trail is definitely a minimalist Groppo designed ultralights whose The first version of this model was airplane. It’s probably a stretch to call it basic features shaped his design philoso- built in 2005 and Groppo says about a Cub clone, but it shares the basic idea. phy in developing the Trail. 112 have been produced with 75 flying The cabin is a welded cage of 4130 During the early 1980s, Europe was in 11 countries, many of them kits. In square-section chromoly tubing which, experiencing a wave of ultralight activ- an inteview last fall, Nando Groppo said à la Mooney, provides crashworthiness. ity that persists yet today. some 37 kits are underway in Germany, That cage comes complete to the builder One of Groppo’s first designs was , the U.K. and Russia. and provides a ready core to start con- the Gropino, an ultralight trike in the Most of these have been Rotax pow- struction. It even has the metal fuel lines Quicksilver mold. (Groppo was an early ered, although there are some Jabiru from the wing tanks to the engine com- Quicksilver dealer in Europe and later 2200 completions, too. As with the Cub partment tacked in place. took on Zenith and Czech Aircraft paradigm in general, Groppo intended Aft of the cabin section, the airframe Works as well.) the Trail to have a utility role, thus many is conventional stressed-skin riveted

Although it can’t be accurately called a Cub clone, the Trail’s tandem taildragger design shares some of the same design points as the Piper classic.

Photos: Paul Bertorelli KITPLANES May 2015 7 The wings fold from a pivot point a third of the way back from the . To make this a single person job, a locking pin at the tip performs the final release, allowing the wing to be walked back and folded. A pin locks the wing in place. aluminum construction over bulkheads own. Besides, Steve Bensinger, Groppo’s a better option and Bensinger told me and stringers. first U.S. dealer, told me a quickbuild there’s no reason a builder couldn’t do Many of those rivets are pop rivets, wing would bust the 51 percent limit. that. (I would.) which speeds and simplifies construc- While the European version of the At the tail is a heavy fabrication tion. There are a few bucked rivets at aircraft has only 15 gallons of fuel capac- that ties the fuselage and empennage the trailing edge of the and ity, the U.S. kit models will have 26 together and provides a beefy attach flaps, for example, but most of the rivet- gallons, recognizing that U.S. pilots fly point for the tailwheel and an optional ing is blind. longer distances. (Or at least they want towing hook. This evidently makes The wings are conventional alumi- the option, bladder capacity notwith- the tail hell for strong because Nando num skin over aluminum ribs with fuel standing.) From the two tanks in the Groppo delights in sitting on the stored in molded nylon tanks in the wingroots, the fuel flows through the horizontal stab for photos. Bensinger wingroots. The ribs are two-piece and aforementioned metal fuselage tubes repeated the feat for my camera. riveted fore and aft to the spar web that via a flexible line that runs through the comes pre-assembled from the factory. cabin. The flexible line is necessary to Folding Wings The factory offers a quickbuild wing allow the wings to fold, but as a crash- If there’s a signature feature to Groppo’s option for European customers, but it worthiness element, it’s none too com- designs, it’s folding wings. While there doesn’t want to ship wings to the U.S., forting to have it just a few inches from are hangars at European airports, there so builders will have to construct their your head. An armored hose would be aren’t many and they tend to rent for

8 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes GROPPO TRAIL

Price ...... $26,250 Estimated completed price ...... $55,500 Estimated build time ...... 500 hours Number flying (at press time) ...... 75 Powerplant . . . . .Rotax 912ULS, 100 hp @ 5800 rpm Propeller ...... GT Propeller 2-blade, fixed pitch ...... Ground adjustable props in testing Powerplant options . . Jabiru 2200, 85 hp @ 3300 rpm

AIRFRAME Wingspan ...... 27 ft 11 in Wing loading ...... 11.84 lb/sq ft The Trail’s panel real estate is adequate, but not generous. In the demo model, to accom- Fuel capacity ...... 26 gal modate the AvMap display, the com radio and transponder were installed on a subpanel. Maximum gross weight ...... 1300 lb Typical empty weight ...... 720 lb what a U.S. monthly mortgage payment Those fixtures will likely be options Typical useful load ...... 580 lb might be. So trailering to and from the for the LSA Trail, as will floats, a full Full-fuel payload ...... 424 lb airport is popular in Europe and that control set for the rear seat, a belly pod Seating capacity ...... 2 Cabin width ...... 30.7 in requires folding wings. luggage compartment, and the parts Baggage capacity ...... 50 lb Bensinger says he isn’t sure if kit to convert to trigear, which requires a builders or North American customers few hours’ work. In the kit version, rear PERFORMANCE for the SLSA version will warm to traile- brakes, controls, and a starter/ con- Cruise speed ...... 87-100 kt ring. “We’re leaving it up to the buyer at trol box are also options. Maximum rate of climb ...... 1200 fpm Stall speed (landing configuration) ...... 30 kt this point. Because the tail doesn’t fold My view is that most U.S. builders will Stall speed (clean) ...... 40 kt yet, it’s still a bit tricky to trailer,” Bens- prefer to park their airplanes in an airport Takeoff distance (to 50 ft agl) ...... 450 ft inger said. Groppo is designing a folding hangar rather than dragging them back Landing distance (from 50 ft agl) ...... 450 ft tail which might complicate construc- and forth between home and the aero- Specifications are manufacturer’s estimates and are based on the tion slightly for the benefit of reducing drome. Hangars just aren’t that expen- configuration of the demonstrator aircraft. the airplane’s width to the gear track—5 sive in the U.S. after you’ve dropped feet 7 inches. At that width, it will eas- eighty grand building something. large. In the SLSA version I flew, the ily fit into one bay of a two-car garage or Second, the nosewheel option. Think steam gauge panel had a single AVmap into a small shed. of what a Maule looks like with its display, a German-sourced radio/inter- It takes one person about five minutes optional nosewheel or what a Cub would com and a Sandia STX-165 transponder. to fold the wings, whose design is really look like on trigear. (Not for nothing But to fit, those had to be placed on a quite well thought out. do they call Tri-Pacers milk stools.) I’m sub-panel under the main panel. The push-tubes disconnect, not a tailwheel purist by any means, but An additional option is the MGL Avi- and there’s a removable pin to fasten yuck. The airplane just looks better drag- onics Xtreme EMS, EFIS, and engine each wing into the spar carry through. ging its tail. monitor pair, plus an iPad mini with The flexible fuel lines remain attached. ForeFlight for navigation. An E/A-B The wings rotate to the vertical—chord- Avionics builder could install about anything wise—and pivot toward the back, where Like other tandems, the Trail cockpit from a Dynon suite to a Garmin G3X; a fixture secures them for towing. is narrow so the panel isn’t generously there’s certainly room to squeeze it in.

Like most tandems, the trail doesn’t have a large baggage area. But it can have a belly pod, which provides generous carrying space.

KITPLANES May 2015 9 The Trail’s interior is no frills, but is relatively spacious for airplanes of its class. To ease ingress, the front seat pivots forward. The welded square section fuselage cage is visible in these photos.

But depending on other instrumenta- doesn’t support that yet, but a builder I’ve been in, especially the front. It’s tion, it may require the sub-panel. could go that route.) definitely more commodious than a J-3. While the space may be a little tight, Visibility from the front seat is excel- the weight certainly isn’t. The Trail is Trail Flight Trial lent and not bad from the back, albeit the a relatively light airplane. In the SLSA It’s no surprise that all of the Cub clones front-seat pilot blocks the view. From the version, its gross weight limit is 1300 look similarly and fly similarly. How front, no S-turns are required during taxi; pounds, not the usual 1320 pounds. could they not? There’s only so much you the view is expansive. Even from the back, Against an empty weight of just 720 can do with 100 hp attached to a top- you can look around the front pilot with- pounds, that’s a useful load of 580 mounted wing with struts. So the Trail out having to sashay the airplane much. pounds. That’s a couple of 200-pounders, is perfectly competent in the company it The Trail has a full-swiveling Matco full fuel and an overnight bag. Not bad. keeps. But it does have a couple of nice tailwheel and Matco toe brakes, so But don’t get the idea that the Trail, qualities, which I’ll get to in a moment. ground handling should be crisp. In the despite the off-road pretensions of First, getting in and out. The Trail version I flew, turn radius was somewhat its name, will haul a bunch of stuff. solos from the front, so it’s easy enough hobbled because the wheel wouldn’t While the luggage area behind the to do the butt-first cabin entry and swing break loose. It took a lot of brake and aft seat beats the Cub’s canvas bread- your legs over the center stick, which is, power to do tight taxi turns. That might box, it won’t hold much volume. (The thankfully, just the right height. take some tuning. weight limit is 50 pounds.) If you had Getting into the rear is another mat- Compared to a Cub, or even Legend’s in mind a little outback camping at ter. The seat is positioned just behind version of it, the Trail’s tail is a little mountain airstrips, the optional belly the cabin walls and would be difficult to slower to wake up. It might feel a little pod might be the way to go. With that get into if Groppo hadn’t thoughtfully different solo, but just as you’re wonder- in mind, a turbocharged 914 Rotax put the front seat on a pivot, so it swings ing when it will come up, it does. From might be a nice engine choice. That easily out of the way. Once ingressed there on, it’s just another Light Sport, would make the airplane a stellar per- into either the front or the back, the with typical climb rates of about 750 former for mountain flying. (Groppo cabin seems wider than other tandems fpm initial and 500 to 600 fpm after

To accommodate the wing fold, the Trail’s fuel lines are flexible Engine and flap controls for the rear seat—optional—are pro- and pass through the cockpit to metal fuel lines attached to the vided via a ceiling-mounted box. fuselage cage.

10 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes that. We easily got to the 1000-foot pat- pitched enough to float a fire extin- the pitch force was so light I couldn’t tern altitude by the mid-downwind. guisher through the glass.) even measure it. One thing I noticed—and liked— The Trail proved a pleasant alterna- As a result, the Trail seems to go about the Trail is its control forces. In tive. In roll, it’s heavy enough to offer where you want it to with no encourage- about half the Light Sport airplanes just the right amount of resistance—like ment to overpitch it. The stall is mild I fly, the control forces range from a heavier airplane such as a Decathlon and doesn’t seem to bite even if aggra- feather light to almost non-existent, or a Diamond DA40. When I clamped vated. When the pitch is disturbed, the with the Czech Sport Cruiser being a fish scale to the stick for an informal airplane finds its trimmed airspeed in the worst in this regard. Light control check of this, it revealed a pound of less than three cycles, which is not atypi- forces are not a good thing, necessar- breakout (including friction) for roll cal of other LSAs. ily. They invite overcontrol and, if the and a little over two pounds for pitch; The Trail has two-thirds span elec- airplane is abused badly enough, actual close to ideal. Someone more expert tric flaps deployed by a momentary structural damage. (A reader sent me a than I would have to refine and confirm switch in the cockpit, from either the photo of a gaping hole in a Light Sport the data, but it felt far more comfortable front or rear. With two aboard, I didn’t canopy, the result of a student who over than say a Remos I once flew, in which notice an appreciable pitch change What’s in the (Big) Box? Unlike other manufacturers, Groppo doesn’t offer the Trail in subkits. When the kit arrives, it’s likely to be a jaw-dropper. It’s in one giant crate as long as the main wingspar for one wing, with all the parts and pieces inside. The welded fuselage section arrives with it, but outside the box, bolted into a protective cover. Plan on unloading a big, 900-pound crate. Current price—firewall aft only—is $26,250 for the taildragger ver- sion, $27,500 for the trigear variant. You can buy a trigear conversion kit for $2,200. Add to that about $1,335 for the engine mount, $820 for the cowling, $215 for a spinner, about $1,200 to $1,400 for a prop. A Rotax 912 will add another $22,000 or so. That’s about $52,000 all-in, less the avionics package and paint. (Prices are FOB to the dealer’s location.) All the kit materials are CNC cut, and sheet stock, with very few exceptions, is pre-drilled for rivets. The hardware is individually Fasteners and small parts are provided in plastic bags, each numbered to correspond to line items in the builder’s manual. packaged in labeled bags that correspond to numbered items in the assembly manual. All of the parts are metal, with the exception of the windshield, the The construction manual itself doesn’t have any explicit assembly or fiberglass cowling and the wingtips, all of which are included in the kit, order of events instructions, just detailed drawings and photos along primed and ready to paint. (As noted, the cowling is an additional charge.) with a checklist to make sure everything gets done. The order of events Wiring harnesses are available as an option, otherwise that’s left to is up to the builder. the builder, as is any additional lighting beyond the basics. Bensinger The Trail kit requires no special tools other than common shop tools, says the estimated build time is about 500 hours. and there’s no requirement to build large jigs or fixtures to assemble it. —P.B.

The kit includes everything from the firewall aft. All the sheet stock and fabricated parts are CAD cut and pre-drilled undersize.

KITPLANES May 2015 11 during flap extension; that might be different while solo flying. At this juncture, I could paste in the same performance paragraph I’ve writ- ten to describe every other Light Sport airplane with a 100-hp Rotax and a 1300-pound weight: About 100 mph on 4.5 to 5 gph. That will vary with prop and engine. The airplane I flew had a two-blade wooden/composite prop, which Steve Bensinger said was overpitched a little. Coarser pitch may get a little more For U.S. kits, the Trail will have Matco brakes and tailwheels. Brakes have simple toe controls. speed. Besides the Rotax 912, the air- plane can also accommodate a Jabiru and added just a taste of power dur- When I asked about support and war- 2200 or a Sauer S 2200. Paired with ing the fly on and stuck it with a little ranty information, he said the details other props, these may or may not forward pitch. It stayed stuck. Overall, were still being worked out. During improve cruise speed. I found the Trail a pleasure to fly and my research for this article, the factory Landing anything with spring gear land and could have motored around was responsive, but for a builder with a can be a piece of cake or a bounce fest, the pattern all day. burning question, there are time zone depending on the pilot’s skill or lack and language barriers to deal with. thereof. The Trail has a single-piece Work in Progress Bensinger says he’s prepared to field any aluminum spring that bolts to the out- Compared to more established kit man- support questions, but again, the experi- side of the belly. As taildraggers go, ufacturers, at least in the U.S., Groppo ence base isn’t filled in much yet. I thought the Trail was easier to land and the Trail is still a work in progress. For experienced builders, this might than most. Bensinger had suggested While Groppo is prepared to ship what not matter, given what appears to be a an approach speed of about 70 mph, appears to be a complete, competent kit, complete kit with good documentation but I found the airplane felt like it was the support structure is still in the con- and a design that isn’t festooned with being forced to fly that fast. So I let it struction phase. weird quirks. It’s E/A-B building 101. settle back to where it wanted to be— But it looks like this is coming For a builder in need of a lot of sup- about 60 mph indicated and 55 over together rapidly. When I flew the Trail port, it might be wise to delay purchase the numbers. In a three-pointer, that last fall, Steve Bensinger’s Lone Palm until Groppo has more kits fielded and a resulted in a satisfying this-airplane- Aero was the only U.S. dealer, and he more mature support structure. J is-done-flying plop on the runway with hadn’t yet completed his own Trail from no impulse to stab the brakes to get a kit shipped to him by Groppo. Since Paul Bertorelli is editorial director of stopped. Wheelies take a defter touch, then, two other U.S. dealers have joined Belvoir Media Group’s aviation division. but not much. I used the same speed the effort, one in Ohio, one in Maryland. He flies his Cub in Florida.

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22032 G3X Connext Ad-Kitplanes.indd 1 1/6/15 7:47 AM KR Airplanes: Affordable, Fun Flying

Chino KR Fly-In showcased this sporty, economical airplane. By Dave Prizio

How often is heard the lament, from time to time, but Glover has come Mark Langford, another attendee, “There are no affordable kit airplanes to terms with the arrangement. He runs has about as much time in KRs as any- anymore, and the ones that come close nVAero out of his hangar at Chino Air- one, with over 1100 hours in make. He don’t even look like real airplanes.” port (KCNO) in Southern California, created a webinar for the EAA web site Many hundreds of KR builders know where he makes parts, options, and featuring a broad overview of the vari- better. Some 40 or so gathered recently complete kits for a loyal cadre of build- ous KR models and their construction. at Chino, California, to show off their ers around the country and around the This would be a good stop for anyone planes, compare notes, attend a few world. At their recent fly-in, a crate hold- thinking about building a KR. You can seminars, and visit a pair of great muse- ing a new kit was addressed to a builder find it at:http://tinyurl.com/ouufu32. ums in their spare time. The proof in Belgium. KR builders are also located Colin Hales flew his KR-2 from Eng- that these little planes can cover some in Brazil, Canada, , United land as part of what he calls the KR-2 real ground is that they came from far Arab Emirates, and various other points World Tour. For more information on and wide—New Mexico, Pennsylvania, around the world. his odyssey, you can check out his blog England (yes, all the way across the Marc Baca, a relatively new KR at kr2worldtour.blogspot.com. He is liv- Atlantic), and more. builder from nearby Los Angeles, did ing proof that a KR pilot can fly almost much of the work of organizing the fly- anywhere he or she wants to go. The People in. He was able to gather KR owners The owner of nVAero, the distributor from far and wide. The two-day event The Planes of the KR plans and manufacturer of featured workshops, aircraft judging, KR planes have been around since the the kits and parts is Steve Glover. The and lots of hangar flying. Eleven planes 1970s, built from plans, and are currently plans are actually still owned by Jea- from seven different states, plus the available in three models. Ken Rand was nette Rand, the widow of the original UK, graced the Chino flight line at one the original designer, and he was rather designer, which can present challenges point, and each plane was unique. small at 5 feet 4 inches tall. He thus

14 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes KR Aircraft KR Airplanes: Model KR-1 KR-2 KR-2S Length 12’-9” 14’-6” 16’-0” Wing Span 17’-0” 20’-8” 23’-0” Wing Area 62 sf 80 sf 82 sf Empty Weight 375 lbs 480 lbs 520 lbs Gross Weight 750 lbs 900 lbs 980 lbs Cruise Speed* 180 mph 180 mph 180 mph Affordable, Fun Flying Stall Speed 52 mph 52 mph 52 mph Typical Engine 1835cc VW 2100cc VW 2180cc VW or Corvair 100 hp

* Cruise speeds reported vary widely depending on the engine used. Colin Hales used a Jabiru 2200 for power. This engine is ASTM certified for Light Sport Aircraft and produces 85 hp. size of each model increased, build- are not for big people, as is evidenced ers looked for more powerful engines by their relatively limited useful loads. designed a plane that was fast, efficient, to maintain climb performance and Two 170-pound people and a reason- fun, inexpensive, but not too roomy. The reach for ever faster cruise speeds. In able amount of fuel will fit if the builder original design was a takeoff of the Tay- fact, claims of fantastic cruise speeds, is careful with the empty weight, but lor monoplane, but has since evolved into some believable, other less so, domi- there is no room, let alone useful load, its own very distinctive design­—or, more nate KR conversations. Of course, an for big guys who push the scale past 200 accurately, set of designs, with different RV driver or two has been known to pounds each or are unusually tall. gear configurations, different sizes, dif- stretch the performance of their plane The standard KR-2S kit sells for ferent engines, and different airfoils. a bit, so we won’t hold that against the $17,500, or you can just buy a set of plans The KR-1 is a single-seater typically KR builders. It’s just hangar flying and for $325 and make everything yourself. powered by an 1835cc Volkswagen all in good fun. Grover also offers a number of options engine. The KR-2 is a somewhat larger Above is a rundown of the various and kit components. It is possible to put a two-seat version that usually gets its models. All are fixed gear and can be KR together for under $20,000, but most propulsion from a larger, 2100cc Volk- built as a trike or taildragger. Informa- people should probably budget about swagen engine or a Corvair engine. tion is from nVAero. $35,000 or so for a complete airplane. The latest version, the KR-2S, is bigger Many builders report empty weights With a stall speed a little over the Light still and can be powered by a number in excess of those listed above, since they Sport limit, a number of builders have of different engines from a 2180cc have made their own improvements Colin Hales and his KR-2, G-BYLP, always Volkswagen, to a Corvair, to a Jabiru, and additions to increase the comfort drew a crowd anxious to hear about his or even an O-200 Continental. As the and utility of their planes. These planes ’round the world tour.

Photos: Dave Prizio, Steve Glover, and Jeff Scott KITPLANES May 2015 15 The sides of a KR-2 fuselage being assembled. Note plywood sides The bottom of the KR fuselage is constructed just like the sides. with wood longerons and . Here the bottom is being glued to the sides. made slight modifications such as using from plans it takes 400 or so hours lon- challenges. If you want a kit that sim- smaller, lighter engines or other creative ger. Of course, build times vary depend- ply requires assembly, along the lines of modifications to comply with the Light ing on skill level and the ability to stay an RV-12, the KR may not be your best Sport Aircraft rules. In recognition of focused on the project. choice. On the other hand, if you enjoy the obvious opportunity to capture these Most builders keep instruments and the company of innovators and tinker- pilots, Glover has been working on a new avionics to a minimum to stay within ers, you may well find a happy home KR-2 design to better comply with the the recommended empty weight and to among your fellow KR builders. rules. No details are available on this new keep costs down. These builders are defi- kit at this time, but expect to see some- nitely not engaged in a battle to see who Flying the KR thing in the near future. can create the most expensive panel. Your author, due to his extra-large size, Most every KR owner flies VFR only, cannot give you a firsthand account of Building a KR and their planes are outfitted accord- the KR’s flying qualities, but a survey The basic KR airframe is pretty simple ingly. As a group they are cost-conscious of the assembled builders and various to construct. The fuselage employs and creative in getting the most perfor- comments on the krnet.org forum paint wood longerons with plywood sides and mance for the least amount of money a good picture of what it’s like to fly a bottom to form the basic structure. The out of their projects. KR. Keep in mind that every KR is a rounded turtledeck is made of shaped The wide variety of engines employed little different from every other KR, so foam covered with fiberglass. The cowl by KR builders can bring some inter- general comments about flying charac- is also typically fiberglass. The wings are esting challenges when it comes time teristics are just that—general. truly composite with wood spars and to get the airplane’s mass within the Builder Adrian Carter talks about ribs mated to fiberglass skins. In the kit prescribed weight and center of gravity the KR’s stall characteristics: “It [the version, the skins come preformed to envelope. Builders must use ingenuity stall] can be quite sudden. You will ease construction and better maintain and more than a bit of custom crafts- feel a buffet, and then next you’re look- the shape of the airfoil. The kit can usu- manship to make everything work ing straight at the ground. Neutralize ally be built in about 1000 hours, but out, but this is a crew that rises to such the stick and pressure back gently—

This KR features the traditional (for KRs) VW engine adapted for The Corvair engine is also popular with KR builders. After many airplane use. These engines typically produce 80 to 100 hp. years of refinement, these engines are proving to be reliable and affordable for builders needing a 100-hp engine.

16 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes more of an engineering challenge than it is with other, more forgiving designs. This challenge is nonetheless met by builders all the time as the wide assort- ment of engines powering KR airplanes will attest. Is the KR for you? If you are a real experimenter who loves the company of other real experimenters, you may find a happy home with other KR builders. If you want to build something that is con- Jeff Scott’s KR-2 in flight. He flew in from Los Alamos, NM. ventional and conventionally powered, something that will hold some baggage and maybe even fly a little IFR, you prob- you don’t want to take the wings off. this phase. I will never land my airplane ably need to look elsewhere. That is not Remember, this is nothing like you have above 60 mph. If I try, and for the first what KRs are about. If you are a big guy flown before. Each aircraft has its own 60 hours I tried all the way up to 80 mph, like your author, the KR is probably not characteristics. Stall speeds vary, and it I will bounce.” a good choice. However, one 6-foot-4- just handles slightly differently.” Other builders describe the KR as inch KR builder simply added 24 inches Another builder, Jim Faughn, talks very light on the controls, slippery, to the length of his fuselage and found about landing the KR: “The KR is prone to floating on landing, and pos- a way to fit himself in, which is the true so close to the ground that you will sessed of a rather abrupt stall. It is very KR spirit—make it your way. J encounter ground effect in avery big sensitive to center-of-gravity loading way. You can and should use this to your due to the very short distance between For more information see these web sites: advantage in making the perfect land- the wings and the tail surfaces. This www.nvaero.com, http://fly-kr.com, and ing. Patience is a huge virtue during makes different engine installations www.krnet.org.

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KITPLANES May 2015 17 Getting 260 mph out of an O-200 Continental just for fun. By Tom Wilson

Racing is about the most fun you can traits that transition well to main- Stephen Partridge-Hicks is English, but have with anything internal combus- stream homebuilding. he races a patriotic Miss USA. For 2014 tion, but it costs everything you’ve got Of course, occasionally the innova- Stephen’s team extensively reshaped and lightened Miss USA’s aft fuselage, with the and just a little bit more. Which is why tion in F1 is overt. Pushers have come horizontal tail next in line for updating. At there is Formula One. When it comes to and gone, and there once was an F1 racer Reno he was removing the rather thick vinyl racing airplanes around pylons, there is with the two mandated maingear tires stars from the cowling as their edges were no less expensive flight plan, other than set in tandem in the fuselage belly, like a apparently catching the wind. That, and a maybe running your spare Pitts in the two-wheel . In the modern era the prop change, netted Stephen first in the Silver race at 221.850 mph. slower biplane heats. path to speed seems paved with com- The working man’s racing class posites, where smooth, carefully shaped motivator. Currently the F1 ranks are since they were called Midgets right skins offer drag reductions. Near-radical dominated by a carefully engineered after WW-II, the Formula One class wing design is another F1 hallmark; the and beautifully executed design known sets hard limits on expensive items last two decades seeing unusually high as Endeavor. It is followed by a gaggle of such as engines and propellers, leav- aspect ratio wings for high-G, maneu- serious-minded developing racers, along ing plenty of room for innovation by verable racers. with a backfield of heritage rag-and- homebuilders. An O-200 Continental But for every wild F1 racer in the tube designs most often run for fun, but engine is mandated, along with a fixed- avant-garde, there are three traditional still capable of amazing performance. pitch prop, 500 pounds minimum models banking on careful build quality And maybe most exciting for budding weight, and no less than 66 square feet or the odd airframe tweak to give them racers, languishing in the rear of han- of wing area. The emphasis is on reduc- an edge. Or maybe they are there just for gars across the country are a legion of ing drag and increasing efficiency, fun with cost containment as the main F1 racers waiting for a little love. Mainly

18 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes Start with a Cassut 111M, couple your imagination to your building skills, and you’ll have an excit- ing time pylon racing. Here Kent Cassels of Salt Springs, Florida, demonstrates his take on the home-brewed hot rod Cassutt; he and Margaret June finished third in the Silver at 207.349 mph.

Cassutts—a plane that’s still well sup- pilot-owner Steve Senagal in 2008, at 260.775 mph, set at last September’s ported—these planes represent one of Endeavor is based in Hayward, Califor- races. That’s just a little faster than the the most approachable paths possible to nia. The wing is foam core and carbon similarly powered Cessna 150. rounding the pylons. fiber, the fuselage Kevlar and carbon With its skinny-stick landing gear, In 2014 we visited the F1 pits at Reno fiber. Ly-Con supplies the thoroughly razor-narrow rear fuselage, and slen- to recalibrate ourselves with grassroots detailed O-200 engine, while the leg- der wing joined at textbook right racing developments. Our partial sam- endary Al Marcucci at Savage Magneto, angles, Endeavor eschews any roman- pling of the racers below are arranged also in Hayward, blesses the old-school tic notions of streamlining in favor of fastest qualifier first. ignition with trick internal timing. The whatever the engineering handbook prop is a Steve Hill Twisted Composite says. Under Steve’s ownership it’s also Endeavor of admittedly not overly new technol- something of checkbook engineering, “Everyone thinks we have a secret, ogy, but, as Steve puts it, “We’ve tried as he and the crew quickly point out but we don’t,” pleads Endeavor crew some pitches over the years, and this they’re the caretakers, not the original chief Cash Copeland. “We fly it before one is the best compromise between builders of Endeavor’s speed. They’ve we come here and it’s ready to go. We acceleration and top speed.” Race pace carefully maintained Endeavor’s win- un-cowl and check for leaks, things is a humming 4400 rpm, resulting in ning capacity, but the breakthrough missing…This has been a very reliable the current 267.289 mph qualifying improvements were there when they airplane.” It’s a familiar story in air rac- record. Steve also holds the race record bought the plane. ing: An exceptional design is well built and paces the field without modifica- tion for years before the competition hammers out a faster unit. Designed by Mike Arnold, first raced by Dave Hoover, and bought by current Formula One Rules Engine O-200 Continental Propeller Fixed-pitch, wood or composite only Minimum Weight 500 pounds Landing Gear 2 x 5.00-5, non-retracting Cash Copeland wheels Endeavor out of the F1/Biplane hangar at the Reno air races Wing Area 66 sq. ft. for another windless, early morning heat race. As smooth as if it was dipped in a vat of —T.W. aerodynamic speed sauce, Endeavor is the current F1 untouchable at 267 mph.

Photos: Tom Wilson KITPLANES May 2015 19 “F1 is for the guy who fiddles all the time. It’s a builder’s class. If you want a working hot rod, this is your thing,” says owner/pilot Steve Temple in Madness’ cockpit. True enough, as Steve and crew chief “Fix It” Chris Dickerson run-in four new cylinders as part of an unplanned, in-the-field top overhaul. All modifications to the class-mandated O-200 Continental engine are tightly regulated to contain costs. A dispropor- nurtured in the quest for F1 gold. This right at the airport for handy unsched- tionately large number of F1 engines includes taking it “down to the mother uled dead-stick landings. come out of Ly-Con in Visalia, California, material,” modifying the tail, adding At Reno Madness qualified second, such as Madness’ shown here. Four-into- one headers into a tunnel air exit are fillets to the horizontal stabilizer, and but then the fun continued with an universal on the fastest F1s. smoothing the wing. unexplained “washboarding” of the cyl- It’s also meant plenty of engine work, inders. Ly-Con delivered four replace- Instead of hardware, the improvement and recently, travel. Steve was invited ments, but ultimately the troubles story with Endeavor is one of the most to an F1 race in Lleida, Spain last sum- continued for an off-pace eighth place privately held topics in aviation and sits mer. A fantastic event with large crowds in the Gold feature race. Not what Steve in the pilot’s seat. Steve came to Reno out just to watch the F1s, it also proved or his team were hoping for, but part of after a childhood ambition for airliners work-intensive for Steve when Madness’ running hard at the front of the field. took him from Watts, to flight instruct- cowling partially delaminated, pop- For homebuilders it’s a lesson that exper- ing, to his own 135 charter operation, ping an 8-inch hole in the carbon fiber. imenting at the limit of performance is and finally, to the left seat of American Cowling bits stood up into the slip- occasionally character building. Airlines iron. All that commercial flying stream as air brakes while other shrap- meant next to nothing when it came to nel sliced the ignition system out of Wasabi flying something light and responsive commission. “The explosiveness of the Like burning magnesium chaff, Elliott down on the deck in traffic, and Steve hole opening up felt like a rod blowing Seguin is one bright wick. Not ful- acknowledges the recent improvements or something,” says Steve, who was no filled with putting on the Mojave have come from his growth as a pilot, doubt appreciative that races are held Experimental Fly-In, plus arranging rather than from the wax and tape Saying it’s silly to build a plane strictly for racing, deep-chested Wasabi was designed for tweaking they’ve given Endeavor. “It’s both long-distance record setting and pylon racing by Elliott Seguin and Jennifer Whaley. taken a while to get out of the mindset of It will take a fresh race engine to realize Wasabi’s full potential as it has been running on a staying away from the ground and other well-used stocker. airplanes,” says Steve, before noting that, parked at the gate, the cockpit of his day- job 747 is the same height as the pylons at Reno. It’s a strong reminder that while fabrication skills grow when building airplanes, flying skills do not—and all the heavy time in the world is of little help in sport planes. Madness Steve Temple’s 240+ mph Madness is one of two Robbie-Grove-designed Boyd GR-7s built. The second met an early end, but Steve has been lovingly

20 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes This trick tool caddy atop Wasabi’s fuselage is more crafty than Crawling under Wasabi shows the new cooling air/exhaust tunnel exotic. The only custom parts are the two curved sections designed added for 2014. Every fast F1 racer uses such a tunnel with the to fit Wasabi; the main portion is a bit of common plastic shelving, a 4-into-1 exhaust exiting through it. They also like to place a fan task lamp and power strip outlets. A single extension cord provides blowing backwards into the tunnel during post-race cool downs power to the lamp and numerous outlets on either side of the unit. when not de-cowling the airplane. a speed week for record setters at Reno 2014, job one was a major belly- Fraed Naught Mojave, and organizing non-stop dectomy, where the fuselage was stood Immersed in aviation for play and work— flights to AirVenture—not to men- on end and gutted like a perch. The flying P-2 fire fighting tankers—owners tion his day job at Scaled Compos- idea was to move the landing gear rear- Lowell and Judy Slatter enjoy the com- ites—Elliott is also a blossoming F1 ward 4 inches to reduce tail weight for petitiveness of F1 racing, but ultimately, racer. Working a shoestring budget faster acceleration during the stand- “We come here to have fun,” says Lowell. (no, not that Shoestring), Seguin’s ing starts. Typical of F1s, Wasabi has To speed up the fun they pur- one-off compositeWasabi is a mixture precious little rudder authority at low chased Dan Gilbert’s second, smaller of advanced sport flying and F1 racing speeds and needs brake intervention for and lighter F1 design three years ago, concepts with a hard-working ama- directional control, something to avoid named it Fraed Naught, and have been teur’s small budget. like a tax audit when starting a race. making what detail improvements As such, Seguin’s engine program is Seguin reports the newly aft gear did they can between all their other com- a wheezing lack of compression await- the trick, with only minimal braking mitments. Some of this was simply ing attention, hopefully this winter. now required. making the airplane a little less of The airframe, however, was designed Of course, “If you’re doing the gear, a handful. As Lowell explains, the by Elliott and his girlfriend Jennifer you might as well do everything down racer is, “…always out of trim and has Whaley (also an Experimental avia- there,” so a new air exit scoop was built no trim tab. It’s only trimmed at 220 tion pro), and is craftily designed for in the belly between the gear legs, à la record-setting, as well as F1. Sleekly the original Nemesis. The new gear is Like almost every small race plane, Fraed molded and constantly updated, for shorter as well for less total drag. Naught’s elevators are over-eager at speed and although the side stick is but 6 inches Fraed Naught’s new owner, Lowell Slatter, wasn’t sure he would be able to attend tall, it is “still incredibly light. I would like to Reno (in the end he did), so young gun Justin Phillipson of Chico, California flew it change the geometry, but that takes time,” at Reno in 2014. In 2013 Justin piloted Outrageous, so he’s quickly building good F1 says owner Slatter. And yes, by F1 standards, experience. Fraed Naught is flying proof a fast wing need not be thin. this is B-1B bomber instrumentation.

KITPLANES May 2015 21 Being active in aviation is the best way of preserving its future. Miles Phillip Goforth had a corner of Knotty Girl’s voluminous 16.5-gallon Conklin was so consumed with assembling his Zero fighter model, gas tank split at the races. He temporarily fitted this plastic he paid the camera no attention. Although his dad Matt had just 5.1-gallon tank out of the Summit Racing catalog, but ended up sold Miss Demeanor, we think Miles will end up flying the real ones getting the original aluminum tank repaired in time, so it proved someday soon. all for drill. mph, otherwise it’s out of trim nose interchange. “Chasing nano-knots,” At Reno this year Matt qualified down. The stick forces are so light, you Lowell calls it. Miss Demeanor at 230.663 mph, then really can’t feel it. Every pilot who’s Unlike many in F1, A&P Lowell stepped aside to let friend Chet Har- flown it remarks that this airplane is assembles his own engines. “I prefer to ris have his first taste of pylon racing a little difficult to fly in the approach build my own engines because that way, as part of a deal where Chet got Matt phase because it wants to run away.” if I win, I can brag about it,” he jokes. In some de Havilland Beaver seat time. Slippery, you could say. 2014 that would have been some bragging Chet also qualifiedMiss Demeanor Slipping to a landing would help, but as his race engine ran hot and the $2,500 and ran it through the heat races Fraed Naught’s long wings and small, back-up engine substituted because there before letting Matt have his one last low-authority rudder didn’t have the was no time to fix the bullet. go in the Gold. Matt knew it was his leverage, so Lowell added 1 inch to the Intercontinental logistics keeps Swiss rudder’s chord and shortened the verti- Miss Demeanor racer and Flying Bulls technician Vito cal tail no less than 8 inches. Now it “has Matt Conklin’s story with his Catto- Wypraechtiger in F1. Vito lives in Salzburg, way too much rudder to race, but you winged Cassutt is a classic tale of every- Austria; his racer hangars at sponsor have to land!” man’s racing. He’s run it as a family Ly-Con’s shop in Visalia, California. Busy In other changes for 2014 Lowell effort, and after all the fun and effort of with Red Bull and unable to come to the U.S. to work on his race plane, Vito could reshaped the fuselage just aft of the competing in the Gold class, he’s selling only add spraybar water to the oil cooler cowling to clean the cowl/fuselage/wing it for family reasons as well. this year. A drive for inventive technology, small frontal area, and max horsepower keeps his vintage Cassutt 111-M consis- tently in the 240 mph range. Vito finished second in the 2014 Gold race.

22 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes After welding, Knotty Girl’s fuel tank Ease of maintenance is one reason for passed a bicycle pump induced pressure Knotty Girl’s sharply tapered teardrop test. The sofa in the background is just canopy fairing. It allows the entire aft one of the comforts of home teams turtledeck to come off the fuselage, bring to Reno’s austere F1/Biplane/Sport meaning easier inspections and repairs hangars. It gets used all race week long. should anything be amiss. last race because he had already sold Predictably, Chet found pylon racing a the plane to another party based in blast and wants to return, even though he Mojave, California. He was “sell- doesn’t have his own race plane (yet) and ing Miss Demeanor because it’s the Reno’s September race dates interfere with responsible thing to do as a parent, not hunting season (he’s based in Alaska). because I’m not having fun.” Our bet is he’ll be back! The pair reported no large techni- cal issues, but did stay busy with small Knotty Girl items, replacing all the engine mount Another grassroots racer, Phillip Goforth cushions during race week, along is a corporate pilot operating out of with the tailwheel. The latter is a Midland, Texas. His Knotty Girl is a consumable because, like many other Cassutt II with an Owl wood wing, but small racers, Miss Demeanor sports like any good racer it’s been modified a Rollerblade tailwheel. The plastic so many times we’d best think of it as a wheels eventually break, but without one-off at this point. harm, and they’re easily replaced from An older design, Knotty Girl is, the stash of Rollerblade wheels Matt fabric, metal and fiberglass, although keeps handy. some parts, such as the just-added 2014 Formula One Gold Race Results

Finishing Position Aircraft Pilot Race Speed Qualifying Speed

1 Endeavor Steve Senegal 252.090 267.289 (record)

2 Scarlet Screamer Vito Wypraechtiger 241.904 239.112

3 Fraed Naught Justin Phillipson 233.883 233.109

4 Wasabi Elliott Seguin 229.256 235.554

5 Quad Nickel Jay Jones 224.100 232.363

6 Miss U Kevin Anderson 223.626 231.048

7 Miss Demeanor Matt Conklin 223.441 211.244

8 Madness Steve Temple 223.290 242.334

KITPLANES May 2015 23 Knotty Girl’s fashionable flat black fuselage Short-span, long-chord wings, such as the classic Cassutt silhouette of Creighton King’s is actually a vinyl wrap right over some Last Lap Player were once thought the fast way. But as Steve Senegal’s sailplane-like rough fabric. The vinyl was an expedient Endeavor illustrates (along with every other fast F1), high aspect ratio wings rule, espe- when there wasn’t enough time to get to cially at Reno’s 5,000 foot altitude. Last Lap Player qualified at 171 mph; Endeavor went the painter’s prior to Reno. 267 mph. Robby Grove horizontal stabilizer, With the gear relocated, the cowling, Phillip builds his own engines, and are carbon fiber. For 2014 the empha- turtledeck, canopy, and upper horizon- while these have remained close to stock, sis was weight reduction, with Phillip tal deck were all reworked or rebuilt for he’s building something racier with ECI trimming a smart 30 pounds from both smoothing and reduced weight. cylinders, stock rods and pistons, and a Knotty Girl. This included Grove Phillip also made the turtledeck easily Pacific Continental camshaft. They make gun-drilled landing gear (runs the removable for maintenance. The belly an exact profile of the F1-spec cam that brake fluid through internal passages will be reworked later; for now empty eliminates the production tolerances of in the spring aluminum gear), and weight is a svelte 553 pounds. the stock bumpsticks; with fiscal good like Wasabi, part of the new gear was Eventually Phillip wants to trade the fortune Phillip hopes for roller rockers to move the CG forward of the gear to wing for a carbon fiber version of the and ported cylinders in the new engine. get the tail up faster during the race- Snoshoo unit, so a few more pounds Besides Reno racing, Phillip sport flies horse starts. may be shed yet. Knotty Girl a fair amount to airshows Pylon Racing for Homebuilders Reno, Nevada, during the National Championship Air Races is the place Phantom can only be beat by the next person willing to build a for pylon air racing, and it offers a wide variety of classes to suit differ- pure-race biplane. ing budgets. The Jet, Unlimited and T6 classes are either millionaires’ In contrast to the somewhat liberal Biplane rules, Formula One is clubs or require an antique Air Force trainer, while Sport, Biplane and international, with strict mandates from the FAI cookbook specifying F1 are homebuilder-friendly. nearly every aspect of the design. This can distort the importance of Sport is an exciting, vibrant class highlighting the best of modern some areas because they are the only ones left open to interpretation, Experimental aviation. The only meaningful engine rule is a 650 and as a consequence, when talent and money combine in a Formula cubic inch displacement limit allowing serious power and speeds, and class, the result is often very difficult to beat. In F1 air racing that plane unfortunately, champagne budgets for the average Joe. So far big-inch is Endeavor, currently piloted by Steve Senegal. Before that, Jon and Lycomings and Continentals fitted to fairly stock Glasairs and Lancairs Tricia Sharp used loads of personal skill, labor, funds, and Northrop rule in Sport, with an emphasis on state-of-the-art engines. If making Skunk Works talent to craft the all-conquering Nemesis. Before them it 700 hp and 1200 pound-feet of torque from a twin-turbo IO-550 Conti- was Ray Cote and Shoestring. nental intrigues, Sport is the class for you. That said, F1 has always had a garage-built backbone. Assembling a Biplane is far more approachable. Pitts Specials in various stages safe, reasonably powerful O-200 Continental is easily obtainable, and of racing specialization are the standard fare, with the odd Skybolt all but the raciest propellers are well understood, so obtaining a work- and Mong Sport making the show. The rules are actually quite able unit need not be financial suicide. There’s no need for an electrical liberal, especially when it comes to modifying the up to 360 cubic system, instrumentation barely bests the Wright brothers, and the inch engines, but it’s still mainly a place to bring your hotted-up sprint races are so vanishingly short nothing wears out. There’s even an Pitts, tape off the top ailerons and have some fun. The exception unofficial spec-racer—the Cassutt—which offers an easy, well-paved is Tom Aberle, who morphed a Mong Sport into the one-off carbon path to flying the pylons. True, a to-the-plans Cassutt is not Gold mate- fiber Phantom. Packing nuclear Ly-Con power from a pure-race 360 rial anymore, but simply assembling a clean, straight example can put Lycoming, along with almost all carbon-fiber construction (the you squarely in mid-field. After that it’s an experimenter’s playground engine mount, center fuselage and lower wingroots are steel tube with any number of airframe tricks to try. in deference to the rules requiring a sport biplane starting point), —T.W.

24 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes to promote F1 racing. Thus, he’s got a larger than normal fuel tank, and the panel boasts UAV EFIS screens, one side for engine stuff, the other for navi- gation. It’s a touchscreen that emulates an HSI, so Knotty Girl definitely out- panels the competition. A constant work in progress, like many in the F1 hangar, Knotty Girl shows her rough spots. But as Phillip says, “It’s not as perfect as we’d like, but it’s here flying.” Last Lap Player Creighton King, owner of timeless F1 make Cassutt and recently featured in KITPLANES® [“Cassutt 111M: The need for (affordable) speed,” September 2014], has a new bond with his race plane: stitches. True to the Cassutt’s heritage as both a sport and race plane, Creighton was ferrying the factory demonstrator to the races when, en route to Wassau, Wis- consin, his cell phone slipped to the floor. Reaching for it, Creighton inadvertently de-latched the canopy, which holed the wing, fuselage, aileron, and vertical tail on its departure. It also gashed his fore- head above the left eyebrow, so along with the Cassutt’s fabric, Creighton himself took a few stitches to retain his skin. Trailering the racer home, Creighton dug through the pile of parts acquired with his purchase of the Cassutt type to come up with a KR-2 bubble canopy that, turned backwards and laid up with a carbon fiber edge, replaced the miss- ing Cassutt lid. Next, race pilot Dave Holmgren found the fuel boost pump (maintains fuel at the carburetor when fuel sloshes to the rear of the tank dur- ing race starts) not free-flowing as much as necessary during cruise flight, so that meant installing a new pump and bypass at Reno. The system powers off a tiny motorcycle battery, which is suf- ficient for the 10-minute pylon races in this otherwise non-electric aircraft. No threat to F1 front runners with its classic Hershey bar wing and everyman’s budget, Holmgren placed the Cassutt sportster fifth in the F1 Silver race at 181.795 mph. Lesson to homebuilders: A (secure) place for everything, and everything in its place. J

KITPLANES May 2015 25 Building a vertical-split cowl for an RV-7A. By Roger Kellogg Four years ago I was at the stage of fit- Placing and attaching the lower cowl that most Sonex aircraft cowls are split ting the engine cowl to my Van’s RV-7A when working alone was quite a chal- vertically, rather than horizontally like project. The engine and prop were in lenge, and I dreaded repeating the oper- the RV cowls. I took several photos and place so that the cowl could be accu- ation after the parts were painted. One started sketching possible vertical-split rately aligned to the spinner. My project post on a popular online forum showed cowl solutions for an RV-7A. is a nosewheel “A” model and uses the a special wheeled cart that a builder cre- horizontal induction cowl, affection- ated just so he could install and remove Vertically Challenged ately known as the slick cowl. The cowl the lower cowl on his nosewheel RV It is not without diligent consideration supplied with the kit is configured as an without needing an assistant. I didn’t that a prudent builder deviates from upper half and a lower half. It was easy like the sound of the problems related to established practices. I wanted an air- to work with the upper cowl half, but fit- installing and removing the lower cowl. plane that would be trouble-free, easy ting the lower half was difficult because Strategically, a week at AirVenture to live with, and could be trusted for the nosegear slopes forward, pushing gave me a chance to chat with a famous thousands of hours of safe adventure. the cowl into the back of the spinner airshow pilot, and over his shoulder I I did not want to create a development as the cowl is lowered. This creates the noticed that the right half of his engine project, or worse yet, a cautionary tale. need for a long slot in the lower cowl, cowl was removed. It immediately looked I recognized that a top seam would pass which is typically covered by a separate like the solution that I needed. Later, directly over the pressurized air volume gear leg intersection fairing/cover piece. while touring the grounds, I observed of incoming cooling air. Air leakage

26 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes The plane that sparked the idea. The author noted that the Top half of cowl as delivered with kit. At this stage, the author vertical-split cowl on this famous airplane might be a better was intending to build a conventional horizontal-split cowl. solution for his RV-7A cowl problem. Challenges associated with installing the lower half of the cowl lead to a quest for a better solution. through this seam would reduce cooling During the creative stage of the where the engine cowl is attached to effectiveness. A seam across the pressur- study, I sketched up two-piece, three- the airframe at the firewall. Piano ized zone might be weaker than the con- piece, and four-piece solutions. Some hinge “zippers” appeared to be most tinuous honeycomb composite part. In sketches showed diagonal seams. Each efficient for joining two fiberglass addition, rainwater on the cowl might solution had a certain quantity of nega- pieces and minimizing the notice- leak through the top seam and soak tive attributes, but the vertical-split able seam. This was the strategy I had the top of the engine. I posted a pro- two-seam solution appeared to be the been pursuing with the horizontal- posal about a vertical-split cowl on an best compromise. At one point, I fabri- split cowl, and appeared to be the best RV builder forum, and as I recall, every cated a bracket at the nosegear leg struc- attachment strategy for the vertical- response was negative, but without sub- ture that used two eyelets to engage the split configuration. stantive supporting logic. lower seam hinge pin, effectively join- So it was set: I had decided on a vertical- Undeterred, planning continued. The ing three bodies on the same hinge pin. split, two-piece cowl with quarter-turn lower seam would need to be offset an That idea was abandoned as it became fasteners at the firewall and piano- inch to the right of centerline so that obvious that it was creating an over- hinge half seams. The piano-hinge seams a single hinge pin could bypass the constrained system. would be offset one inch to the right to nosegear leg. Coincidentally, the top Three years of lurking on an RV avoid the nosegear leg and quarter-turn seam would also be offset an inch to builder/flier forum, as well as discus- fasteners. In addition, the seams would the right to register with the quarter- sions with other builders, lead me to be overlapped and reinforced to avoid turn fastener brackets that were already believe that quarter-turn fasteners aforementioned problems of air leakage attached at the firewall seam. were more durable and easier to use and strength.

The top cowl half was cut into two quarters, and the two top The two bottom quarters have been joined by piano hinge. quarters were joined by a piano hinge. The seam is offset one Cosmetic finishing and the gear intersection fairing remain to inch to the right from centerline. be completed.

Photos: Roger Kellogg KITPLANES May 2015 27 The process of fitting the silicone baffle seal was made easier Modifications to the inner surface of the cowl were necessary to by being able to remove one quarter of the cowl at a time. This create suitable surfaces for the silicone baffle seal to strike against. picture was taken before the top hinge was attached. Two white patches of micro are visible at the center seam, creating a strike surface for the front and rear baffle seals. In every case, internal pressure pushes the seal against the strike.

Making the Cut inner skin along each side of the seam other places it added challenge. The baf- Eventually the studying was done, and and tapered the edge of the honeycomb fles around the left inlet and engine air it was time to commit. New seam lines back 45 degrees. When the inner fiber- filter snorkel were especially challenging were drawn on the cowl. The old hori- glass surface and Nomex honeycomb due to lack of space. Some pieces of sili- zontal seams were temporarily fastened were ground away, the remaining outer cone baffle are attached to the cowl half together with Clecoes and aluminum fiberglass flange went wild and wavy. and mate against an aluminum strike strips. With a certain amount of trepi- Exposed honeycomb cells were filled on the engine, while most are mounted dation, I took a razor saw to the grace- with dry micro and layered in two stag- to the engine and strike against the ful composite cowl halves and turned gered strips of glass tape to provide an inside of the fiberglass cowl. The transi- them into cowl quarters. The razor saw edge that would support the riveted tions between baffle seal mounted to the was slow, but afforded the smallest kerf piano hinges. To correct the wavy edge engine and baffle seal mounted to the width, making reconstruction easiest. problem, thin flat strips of oak were cowl were the real challenge. These are Once cut apart, the cowl pieces showed a clamped to the inner and outer surfaces the points that will see relative motion small, but manageable, amount of stress- of the layup during cure, using Visqueen as the engine rolls about its longitudinal relief relaxation. Most of the cut length as a release ply. Results were pleasing. axis. Careful study, multiple attempts, was through the honeycomb-stiffened The engine airflow baffles would need minor adjustment, and testing eventu- area of the cowl, which would need to be re-engineered to work efficiently ally led to a working solution. In all reinforcement before attaching piano with a cowl that would now approach cases, the high-pressure air energizes the hinges at the new seams. I ground away from the side rather than from the top. In silicone baffle seal against its respective an inch-wide zone of honeycomb and some places this simplified the baffles, in strike surface. Having the cowl cut into

This view looking toward the left inlet shows a gap remaining A pocket was created for the top pin badge. Eventually quarter- between two pieces of seal. This was eventually corrected by a turn sockets were riveted to the two blue holes. larger replacement piece.

28 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes At first glance, a split cowl would not surprise the typical RV The new right cowl half after joining the side seam. The left cowl builder—until he realized it was split vertically! Shown here are half is visible on the plane. the left and right halves with piano hinges riveted into place. quarters at this stage made engineering eliminated all external evidence of the testing. The engine was run several and fitting the engine baffles much easier former side seams. The top seam, which times to check for contact between the than working with a two-piece cowl. was fabricated with an overlap to hide engine and cowl, resulting in minor the hinge eyes, was tightened up with corrections. An industrial-strength leaf Final Adjustments micro and mold release wax to mini- blower was used to pressurize the cowl With the baffles completed, it was time mize cooling air loss and visual distrac- and study deflection and air leakage to make final adjustments at the side tion. The inside of the cowl was shaped expected in high-speed flight. Deflec- seams and turn the cowl quarters back so the rear baffle would seal cleanly tions were small, and no leakage was into cowl halves. The quarters were across the hinge seam. seen. With insight from ground testing Clecoed to the fuselage, and the exte- A split nosegear intersection fairing in hand, fabrication continued. rior seams were glassed. After cure, the was built up with clay, micro, and cloth. A flush badge was fabricated out of inside seams were glassed to provide Both halves of this intersection fair- aluminum to hide the access point for strength. Trial fitting of the vertical- ing are integral with the cowl halves. the top seam pin. The badge was formed split cowl halves was promising. All but The process of adding and removing to match the contour of the cowl and one strip of the silicone rubber baffles material continued until no fastener wraps over the front edge behind the naturally fell into proper position as the was needed at the gear leg intersection spinner. The badge is attached with two cowl halves were installed. That problem seam. In retrospect, a bit of clearance small quarter-turn fasteners to reduce baffle strip still requires special thumb should have been left for the thickness the number of loose pieces that must be action for proper positioning. of paint on the gear leg fairing. installed and removed. Additional fiberglass work contin- Before painting, the vertical-split The lower hinge pin is installed and ued on the cowl. Micro and sandpaper cowl system was subjected to ground removed from the rear of the air exit

Final beveling and trimming of the side seams before joining. Wow! Even with just a witness coat of primer it looked good! Joining the side seams was delayed as long as possible since being able to remove a single quarter of the cowl at a time made work on the baffles much simpler.

KITPLANES May 2015 29 Initial ground testing to check for contact between cowl and This view looking into the rear of the exit scoop shows the seam engine. Several minor changes were made to improve baffle offset to the right of the nosegear. The yellow bent end of the hinge sealing. The plane was anchored to a pickup truck (not shown). pin is the self-retaining feature, passing through the small strike on Pictured are the author and his sons, Andrew and Jon. the left to prevent the pin from working its way out of the hinge. scoop. The pin is retained by a springy multi-tool. This system has no loose from the front. It is on a silver surface, loop that hooks into a hole in a strike screws that must be fumbled with when and I didn’t spend as much time finess- plate on the left cowl. A thumb press installing/removing the cowl. ing this joint, since it is not part of the loop is formed into this end of the pin I did not want to have to climb in and air leakage issue. A bit more attention to make it easy to squeeze the spring out of the cockpit to remove or install at the paint prep stage might have made loop to latch/unlatch the pin. This rear the cowl, which eliminated the possi- this seam disappear also. exit pin access eliminated the need for a bility of a rear removal top pin. Van’s cowl alternative to the slick beauty badge to hide the lower pin, but Initially, my beauty consultant/ cowl is a cowl with an integral engine requires one to kneel beside the plane to financial backer expressed some con- air intake snout under the spinner. This install/remove the lower pin. cern that the top seam would be an cowl is typically used with carbureted eyesore on the world’s most beautiful engines. Since this inlet snout is on the Additional Considerations airplane. Since it has been painted, all centerline and flairs into the exit scoop, When removing the cowl, it takes a bit she sees is the graceful absence of the the lower seam on a vertically split cowl of thought to find a safe place to put the side seams that a horizontal-split cowl becomes a bit more complicated. A ver- cowl halves and hinge pins/badge, espe- would have. The top seam is relatively tical split would probably require three cially on the ramp. Painted surfaces must unobtrusive, partly because the top seams between the cowl halves: a top not be scratched. The hinge edges must color is a deep blue, but mostly because seam, a seam at the bottom of the snout/ not pick up dirt. Cowl halves with a low the eye is viewing the seam from a tan- scoop, and a short seam between the CG are less likely to play tumbleweed gential angle, and not facing the gap as snout and the spinner. Even with this when the neighbor’s T-6 taxies past. you would on a side seam. The lower complication, a vertical-split solution The hinge pins are lubricated and seam is somewhat more obvious, at least would be simpler than a horizontal split tend to pick up dirt and leave black aluminum oxide stains on fingers and clothing. Perhaps a wax lubricant will be cleaner. There are times when speedy removal is valuable; think carburetor fire. Hinge pins typically come out quickly. Fewer fasteners and captive fasteners win this contest. Easy access to fasteners is good. A cowl that is easy to remove/install makes it more likely that visual inspec- tions will occur frequently, which should enhance flight safety. A perfect cowl would be removable without the need for tools. Removal of this cowl requires just a #2 Phillips screwdriver for the quarter-turn fasten- Inspection following first taxi test. Additional clearance was created for nosegear fairing ers. I typically use a stubby or a Gerber and exhaust system. The cowl needed less correction than the wheelpants did.

30 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes A wraparound badge covers the access to the top pin. Badge is Lower seam splits the nosegear intersection fairing. The two halves retained by two captive quarter-turn fasteners. interlock and eliminate the need for loose fasteners. through the air inlets, which has four more than adequate, but the weather with the compromises made by this con- seams that must be joined. The author has been pleasantly cool during testing. figuration. Removal and installation is graciously leaves the development of Theoretically, either half of the cowl quick and simple, especially compared to this possibility to others. can be removed independently, but in several horizontally split cowl airplanes practice it is easier to remove the right that I have worked with. Not having to Preliminary Test Results half first since the oil dipstick door pro- fight gravity while fastening the lower The airplane presently has 80 hours vides a convenient handhold. Once the cowl is wonderful. Elimination of the on the Hobbs, and the cowl has been right half is removed, grabbing the edge seams (and loose screws) at the inboard installed and removed perhaps a hundred of the seam provides a handhold for side of the air inlets is a huge satisfaction. times, both during building and the test removing the left half. At installation, Aircraft performance is equal to the flight phase. The cowl shows a bit of wear the left half goes on first. horizontal-split configuration. It is obvi- between the fiberglass and the quarter- ous that the vertical-split cowl concept turn fastener brackets. This likely would Was It Worth It? works. I would do it again! be the same for a horizontal-split config- It is an accepted truism within the uration. No deflection or pillowing of the homebuilt aircraft community that any More Improvements cowl top seam has been evident in flight. departure from the designer’s plans will If I were to repeat the process, I might Minor evidence of air leaking through take longer than staying between the lines. worry less about reinforcing the edges the pressurized top seam has been seen, My experience with the vertical-split cowl of the composite cowl, as it is remark- as witnessed by dust/soot tracks. The on an RV-7A certainly has not disproved ably stiff. This might have saved a bit of volume of air leakage is small, but justi- the rule. Every design is a compromise. weight. A cooling plenum might have fies the effort in creating a tight seam in After living with the vertical-split cowl simplified the baffle issue a bit, but at this location. Engine cooling has been for a short period of time, I am pleased the expense of introducing other main- tenance compromises into the system. Having lived with this configuration for 80 hours, it seems preferable to access the bottom hinge pin from the front, rather than from the rear. A sec- ond badge would be needed below the spinner. This small change would allow cowl installation and removal without the need to kneel on the sometimes soggy ramp. J

Much of the content of this article is a result of responses to a posting that I made on the VansAirForce.net forum about the completed vertical-split cowl project. It is good to have friends, even ones you haven’t Finished product, after first flight. really met yet. You may contact the author at [email protected].

KITPLANES May 2015 31 Vinyl G raphics Colorful alternatives to the plain plane. By Eric Stewart

Vinyl graphics guru Karl Grove in DragRacer at the National Championship Air Races in Reno. (Courtesy of Tim Adams Photography)

With the advent of CNC vinyl cut- has brought this expertise to DragRacer, applications, but for aircraft, what you ters, decals—be it N-numbers, tail art, and we sat down to ask him how a want to look for is a vinyl with non- or holographic purple flames—have homebuilder goes about getting custom permanent adhesive. This is because become readily available and affordable graphics on their plane. permanent adhesive decals can be very for pimping your ride. At Reno 2014, KITPLANES®: Let’s begin with the hard to remove, and if you do get it off, KITPLANES® caught up with graphics- vinyl itself. What kinds are there and it tends to leave a lot of residue. You are meister Karl Grove in the biplane pits. which are best for aircraft use? then forced to use a solvent to remove If there’s a plane with more decals on Karl Grove: There are a lot of differ- the adhesive, which can then harm the it than Karl’s Pitts S1S DragRacer any- ent substrates to choose from. A sub- aircraft finish, especially on a fabric-cov- where in the world, we haven’t seen it! strate is the material upon which the ered aircraft like my Pitts. Karl works for E-Z Up, a company printer prints. It could be something as Depending on your decal design, you that specializes in instant pop-up struc- simple as banner vinyl or some type of will either be digitally printing artwork tures for indoor and outdoor trade high-end air-release substrate for cop- in full color or simply die cutting from shows and business. These structures ing with compound curves to mitigate a solid color vinyl. An example of the typically feature a company’s logo, and wrinkles and bubbles. You’ve got some former would be custom artwork for Karl has extensive experience in mar- very modern substrates from companies the tail or nose, while an example of the keting and branding. It’s clear that Karl like 3M and Orafol for lots of different latter would be N-numbers. One of the

32 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes nice things about custom vinyl decals is that they are backed up to a transfer tape. The transfer tape holds all of the letters, numbers, and images in correct position to each other so that every- thing transfers to the aircraft exactly as it came off the printer. KP: Are there any particular brands or year-ratings of vinyl that you recommend? KG: Yes, you want to buy a vinyl with a UV or aqueous coating, which most exterior-rated vinyls have. If the aircraft Karl Grove’s pit belies his work for E-Z Up: In addition to numerous vinyl decals on DragRacer, spends much time outside a hangar, the his rail skirts, backdrop, chairs, and even team shirts all feature digital graphics. (Courtesy of Karl Grove) decal will turn yellow, crack, and peel if you do not have these coatings. The year I am not an expert on high-speed appli- So you want to avoid harsher chemicals ratings [vinyls and substrates are typi- cations, but I would imagine there are like acetone, since they will eat through cally given year ratings, for example a 3-, some safety considerations regardless of the laminate or any vinyl for that mat- 5- or 10-year rating, with higher-rated aircraft, such as not putting a graphic in ter. If you buy a pre-made vinyl sticker vinyls being more expensive] are more front of an air intake or where it could like a flag or whatnot, most likely it will meaningful for the vehicle industry jam a control surface if it came off. But have been laminated. However, if you since cars are typically outside a lot more as for me, I’ve never had one peel off. have a graphics store custom print your than aircraft. As I previously mentioned KP: Will washing the plane damage graphic, you need to specify to them to though, if your airplane is tied down the vinyl? laminate it after printing. outside, you may want to spend extra KG: Not at all. I recommend using a For removal of both permanent and for a higher quality exterior vinyl. On mild soapy solution, and you can actu- semi-permanent decals, use a heat gun the other hand, if you are keeping your ally wax over the decal as well. You just to soften the adhesive. I would not rec- airplane hangared, any quality vinyl need to be careful not to lift up the ommend using a hair dryer—it’s not should last forever. Some of the decals edges. As long as the digitally printed the right tool. With a good heat gun on my Pitts have been on for four years, decals have been laminated, you are you have more control, and you know and they still look brand new. not going to damage the printing. That exactly how much heat it is putting out As far as peeling, I’ve never had a is an important point; after decals at the different settings. If it is a metal problem with the semi-perm adhesives. go through the printer, they then go aircraft, it’s not so crucial—you can get We are going over 200 mph and have through a separate process on a lami- it fairly hot. But on a fabric or compos- never had a problem. I know some of nating machine, which essentially clear ite aircraft, you obviously don’t want to the jets are using vinyl graphics as well. coats the decal with a protective layer. get it too hot or you could cause serious

Karl Grove demonstrates the ease of applying a transfer tape vinyl decal. Only the red and blue sections are vinyl—the white background is actually the airplane. First peel the wax backing from the sticky side of the decal. Position the decal and, starting at one edge, press it against the surface with a flexible applicator (available at any hardware store). The translucent transfer backing holds the elements in the correct relative position while you rub. Once the vinyl is adhered, the backing is peeled away to reveal the transferred image. It’s as easy as that, and many of the new vinyls have micro channels within the adhesive to prevent bubbles forming under the decal as you squeegee. For decals that require positioning, try this: fill a spray bottle ¾ full with water and add either 2-4 drops of baby shampoo or rubbing alcohol (approximately 1 part alcohol to 10 parts water), and lightly mist both the location where the decal will go down as well as the back of the decal. This will allow you to slide the decal around a bit before squeegeeing. You should be able to squeegee out most of the solution, and what little remains will eventually evaporate through the decal.

Photos: Eric Stewart KITPLANES May 2015 33 The left edge of this decal lost color when Bruce Eicher’s RV-8 Hula Girl is an excellent example of all that can be done with vinyl. exposed to a mild solvent because it had Amazingly, the only paint on the entire airplane is the yellow cowl and spinner. Every- not been properly laminated. thing else is vinyl. Although it features a variety of WW-II motifs, Bruce says Hula Girl’s color scheme is not based on any particular warbird. (Courtesy of Bruce Eicher) damage. So use a low setting, hold the decal with an even larger one, I would there is some software out there that gun six to eight inches from the surface, recommend against this. can scale up rasterized images, but only and keep the gun moving over the whole KP: Can you give some tips for creat- so far. When it comes to logos, you are decal for 30 to 60 seconds. It should ing the artwork itself? almost certainly going to be designing be hot to the touch, but not burn your KG: Regardless of whether you do something that is a vector-based image fingers. That is the point where you can the artwork yourself or have a graphic because you might want to scale that grab an edge and it should just peel off in artist do it, the first thing is to make sure image down for a business card or scale one go if it is semi-perm. you understand the difference between it up to put on a billboard. The size limit With a perm adhesive, if you are lucky a vector-based image and a rasterized is really only the size of the machine the decal will lift. But more likely than image. A vector image is scalable with- printing the image. not it will break, and you’ll spend a sig- out becoming pixelated or loss of resolu- There are numerous software pack- nificant amount of time peeling it off tion. A rasterized file, on the other hand, ages for creating images. Photoshop is flake by flake. Although I suppose some is an image of fixed resolution that will OK, but Adobe Illustrator is the tool might be tempted to cover the offending lose definition if it is scaled up. Now, of choice, and that is where you design Victory Girl Custom Nose Art Artist Jerri Bergen of Victory Girl (www.victorygirl.com) has created nose for airplanes and is what I prefer to use. If the client has an image that art for hundreds of clients. We asked her to explain what’s involved. doesn’t require repainting or only minor design work, it may be as little KitPlanes®: What’s the basic process for creating a custom image? as $150 to $300. It just depends on how much time we spend. To put it Jerri Bergen: I usually first make a quick sketch or use a sketch pro- in perspective, I like to tell clients, “You are probably going to pay less vided by the client, and then make a painting from the sketch once the for this than for one set of tires that may last you three years—and this client gives their approval. I then send the file to a local vinyl shop to could last the life of the plane.” I also give the client the electronic files print and cut. What takes the most time, of course, is painting; creating so that they can do reprints if necessary in the future, or use the image the sketch is not terribly hard, especially when a client already has an elsewhere, like on a shirt or business card. image sketched or printed out. But a lot of times they say, “Put my wife KP: If a client brings in an image from a book or the Internet—say in front of a Corvette,” and that’s where I draw on my creative skills as a Vargas girl—is that legal to use? How do you distinguish between an artist. I understand the anxiety some people feel by being unable to public domain and copyrighted material? get an image out of their head and onto paper. So my job is to help with JB: That’s an excellent question, and the answer is often fuzzy. Much that, to envision what they are after. Once they have a sketch in front of nose art we see today is derived from artwork put on WW-II combat air- them, it’s much easier for them to say, “That’s exactly what I wanted,” craft, and that art was re-creations of pinups by Vargas and other pinup or “No, that’s not it—can we do something else?”. artists of the time; those images have become public domain. The most KP: What is the typical turnaround time and price of a project? important distinction is whether the end use is personal or commercial. JB: Timewise, I try to work by the client’s schedule. Depending on A design for your personal plane is considered personal use and does the complexity of the project, turnaround is typically 10 to 15 business not violate copyrights. However, once I create that design, I would not days. I have clients all over the country, so most of this is done via email. be able to sell it, nor could the client use the image commercially for a A full image may run between $600 and $1,100, which includes company logo, web site masthead, T-shirt design, etc. decals on a high-performance vinyl called Arlon—it’s a great material If the client did want to use an image commercially, we would either

34 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes (L) The Hula Girl artwork was a purchased Photoshop art file (no longer available) from an online stock house, while the Hula Girl font came from a shareware (free) download called Brush Stroke Fast. (Bruce married his wife Katie in Hawaii; hence she is his Hula Girl and G.I.B. [Girl in Back]). (R) As anyone who has polished an airplane knows, polishing the underside can be a headache. Wrapping the wing bottom precludes this. Although Hula Girl’s invasion stripes stop at the leading edge, some polished planes run the stripes over the top as well to reduce potentially canopy-melting reflections from the polished wing. Note the machine gun ports, which Bruce photographed on a museum P-51 and then had printed at a local sign shop along with the rest of his graphics. (Courtesy of Bruce Eicher) vector-based imagery. Everything you before investing in Illustrator, but if you want to wrap the aircraft, I’d suggest see at my booth—airplane decals, par- don’t have any experience at all, it might a company that specializes in aircraft tition walls, shirt logos—was designed just be better to go to a professional. wraps like AircraftWraps.com. on Illustrator. In fact, I drew the air- If you are looking to outsource the As far as copyright issues go, you need plane in Illustrator to meet the RARA artwork, I’d suggest talking to a car to be careful. A lot of large companies requirement to show egress and location wrap company to begin with. Often are very aggressive against intellectual of the battery and fuel. those companies can do simple decals, property infringement and do not want However, if you’ve never used Illustra- and they understand vehicle applica- you printing their logos. I can’t imagine tor before or have no design experience, tions. They’ll know the best substrate why you would want to put someone’s there is a pretty steep learning curve. for the local climate, and they should logo on your aircraft that isn’t a sponsor, There are some free, simple programs have access to graphic design resources but it’s not recommended. Especially at out there if you want to give it a try or personnel. That said, if you actually a place like Reno where there is so much

change the image enough to be considered original, or get permission KP: Any particular subjects to be careful with? from the original artist. We’ve done both here at Victory Girl. And there JB: Yes, we have had clients receive negative feedback on images are always exceptions: Disney created over 1200 squadron insignias that were deemed anti-Semitic or misogynistic; some people are simply for the military during WW-II, yet today the Disney Company does not not aware that German kill markings or Vargas-type nose art are his- permit recreating those images for commercial use. For example Disney torical images. My best advice is that if it’s the least controversial, show denied our request to recreate a “Dopey” nose art image for a P-38 the artwork to an objective third party for their impressions. national association T-shirt design. —E.S.

(L) Precious Paula’s nose art started out as a sketch of the pilot’s wife. (R) The final image in full color vinyl on the plane. (Courtesy of Jerri Bergen)

KITPLANES May 2015 35 In keeping with Hula Girl’s military color scheme, the fuselage sides sport typical WWII- markings. Bruce notes that he applied the major pieces of vinyl before polishing, but not the detail graphics such as lettering or stars and bars. This worked out fine, but he did note that polishing before applying vinyl might have saved time spent masking. See the June/August 2014 issues of KITPLANES® for a two-part article on polishing. (Courtesy of Bruce Eicher)

media exposure, you are asking for trou- the aesthetic that you are looking for. ble if you have copyrighted logos with- Having colors and letter fonts already out permission. chosen is also something that is easy to KP: What are vinyl graphics likely do ahead of time and will reduce the to cost? billable hours. KG: If you have the image file KP: Your pit looks like one of the already, a simple decal or logo the size Unlimited camps—you’ve got decals of a business envelope will run about not just on the plane, but on chairs, back $10. Expect to pay slightly more if it’s walls, partitions… to be die cut, which I highly recom- KG: Yes. E-Z Up is one of my major mend over cutting it out yourself with sponsors, and they’ve been behind Drag- an X-Acto knife. Racer since we first came to Reno four Design work is where it gets expen- years ago. So the partitions, rail skirts, sive—anywhere from $45 to $85 per shirts, etc. not only give an instantly hour. For just a simple text-based recognizable look to the DragRacer logo, this could probably be done in pit, they also allow me to showcase my an hour. If it’s a custom image that other sponsors. So if you come up with requires tweaking of size, colors, and some custom artwork or logos for your I commissioned an artist (my father, David wrapping with text, 5 to 10 hours is airplane or business, companies like E-Z Gamble) to draw a nice picture to put on not uncommon. However, even if you Up can provide an integrated package of the nose of my RV-6, more or less to play leave the artwork to someone else, pro- products to add some pop to your han- along with the military fighter motif. The viding examples of similar artwork gar or workshop. J resulting picture was delivered as a col- that you like, examples that you don’t ored pencil drawing on coarse paper (Top). like, or even a hand-drawn sketch can Check out Karl’s future Reno rides at The first step was to digitize it using a digi- help the designer quickly pinpoint www.groveaero.com tal camera. That was the easy step— the next step was to spend many, many hours making the colors clean and solid. This necessitated a foray into the exotic and esoteric skills needed to work in a complex digital editing program called GIMP, which is a fantastically powerful tool in addition to its best feature: it’s free. Working at what felt like the molecular level (i.e., pixels) was the only way to get the crisp edges for a high-quality image. After printing the image in color and taping it to the airplane to confirm the dimensions, Glasair III full wrap by Plane Vinyl, Inc. Company owner Dan Black recommends full wraps I contacted a vinyl printing outfit and had be done by professional certified aviation wrappers, since other retail wrappers may not the final image printed up (Bottom). be aware of special requirements for aircraft (not covering static ports, providing for drain – Dave Gamble, N466PG holes in control surfaces, etc.). (Courtesy of Dan Black)

36 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes

Near the Finish Line When your plane is almost completed, it’s time to shop for insurance. By Shanna Linton and Jennifer Cummins

Many homebuilders are caught off insure the fly-off period may be smaller. Pilot Hours guard by the often stringent training For example, Kitfox, Rans, Glasair, Minimum pilot hours are an impor- requirements and cost of insurance Sonex, and Lancair may only have two tant factor in the process of insuring for the first year of flying coverage. A or three companies insuring them, a recently completed plane. Required higher potential for loss drives insur- depending on the model type. Some hours vary, depending on which model ance companies’ strict requirements, of these models could only have one. you are building. It can be quite shocking but with knowledge and planning, you It’s much harder to place insurance for to complete your aircraft and be ready to can meet their conditions. Here’s some uncommon kit aircraft, as there are not fly, just to be told you do not meet the pre-completion advice to those of you enough flying for insurance companies insurance companies’ minimum pilot still in the build phase. to decide rates, so fewer are willing to requirements. The table shows sug- Right now, Van’s Aircraft is among quote them. gested minimums for ratings and hours the most popular of homebuilts. Cur- The fly-off period generally comprises for a few popular homebuilt aircraft. rently, eight companies offer insurance the first 40 hours the aircraft will be Note these suggested minimums will for Van’s RVs. However, out of those flying after you complete it. The fly-off not necessarily exclude you from getting eight, only a few offer coverage dur- hours required can sometimes be lower quotes, but are just recommendations to ing the fly-off period without cover- depending on the propeller and engine acquire the best price for your first year. age restrictions. For other kit aircraft, combination or if your plane is classified In order to obtain coverage with a stable, the number of companies willing to as a Light Sport Aircraft. dependable insurance company for more

38 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes complex aircraft such as a Lancair, you’ll need to be a higher-time pilot with time in the aircraft you wish to insure. If you do not have any time in your type, how- ever, there are a few newer insurance Near the Finish Line companies willing to offer quotes. Types of Coverage Not all insurance is the same. Make sure If you’ve built a Van’s RV, you may be able to train in any Van’s model with the same gear you understand the different kinds of type (tailwheel or trigear) as your aircraft. (Photo: George Ford and Stephen Christopher) coverage available. • Ground and Flight: Provides physi- insurance broker for full flight insur- in a model that you are not building, cal damage and liability coverage ance quotes well in advance of the time however, it is advised that you verify while the aircraft is flying, taxiing, you’ll need them—three to six months instruction in the planned model will and on the ground. as a rule of thumb—so you can gauge the be approved by the insurance com- • Ground Not in Flight: Provides time and expense of training require- pany. For more complex aircraft like physical damage coverage only while ments. Once your broker works with you the Lancair Evolution, you will need the aircraft is taxiing (off the active to select an insurance carrier, you will to plan on a more extensive training runway) and while on the ground. know how much dual instruction the program. There are several places for The liability portion of the coverage insurance company requires. The quote you to do this; ask your broker for applies while flying, taxiing, and on may also list solo requirements, which more specific information. the ground. you must fulfill in your aircraft prior to For Glasair, Sonex, and Rans air- • Ground Not in Motion: Provides carrying passengers. craft, the insurance companies likely physical damage coverage only while will require you to train in the same the aircraft is not in motion (under its Transition Training model you have built since these manu- own power). The liability portion of After you receive the quotes and select facturers are not as common and do not the coverage applies while flying, taxi- a carrier, you can start planning tran- have as many similar models available. ing, and on the ground. sition training. The insurance com- Understandably, this is a lot of infor- • Liability Only: Provides no physical panies that insure the fly-off period mation to digest, especially when com- damage coverage, only liability while understand that this can be difficult, pleting the aircraft is your first priority. By flying, taxiing, and on the ground. and may provide some leeway on the planning ahead, you can make the transi- • Storage: Provides hull and liability model in which you train, depending tion from workshop to cockpit smooth. coverage only while the aircraft is on the aircraft. The new Additional Be sure to contact your broker for any not in motion (under its own power). Pilot Program may help in some cases, questions or concerns you may have. J The liability portion of the coverage and more kit companies are commit- excludes passengers. ted to helping with transition train- Shanna Linton and Jennifer Cummins ing all the time. If you’ve built a Van’s are homebuilt insurance specialists with Dual Instruction RV, for example, you may be able to NationAir Aviation Insurance. You can Another variable that inevitably comes train in any Van’s model with the contact them at: [email protected], up is how much dual instruction is same gear type (tailwheel or trigear) as (877) 577-8267 or jcummins@nationair. required. We suggest you contact your your aircraft. If you plan on training com, (855) 538-8267.

Suggested Minimum Suggested Minimum Additional Suggestions Certificate/Ratings Total Logged Hours

Van’s RV-10 Private pilot 300 Have IFR rating

Van’s RV-12 Student Varies Private license preferred

Van’s Other A Models Private pilot 100

Van’s Tailwheel Models Private pilot 250 (25 tailwheel)

Lancair Evolution Private/Instrument 1,000 100 hours in type, at least 100 retractable hours

Lancair Legacy Fixed Gear Private/sometimes Instrument or Retract 350 to 400 If retractable gear: 100 retractable gear hours

Photo: Richard VanderMeulen KITPLANES May 2015 39 Where the Rubber Meets the Runway Understanding gyroplane nosewheels. By Roy Beisswenger One of the big differences between relative wind to build rotor speed for earn a mechanical engineering degree gyroplanes and helicopters is the land- takeoff. The transition from ground in order to design wheels. That lack of ing gear. That’s because helicopters don’t to flight in a gyroplane is actually a lot excitement doesn’t take away the impor- need landing gear, other than skids to more similar to an airplane than it is to tance of wheels, steering, and shock rest a while on the ground. After all, a helicopter. So all you airplane build- absorption in aircraft design. the big advantage of a helicopter is its ers—stick with us! In fact, gyroplane wheels have to be powered rotor, which gives it the ability far more versatile than the wheels on to lift off vertically to a hover and then Wheels Aren’t Glamorous your car. True, a gyroplane is designed build forward speed for a climb. Unfortunately, on a gyroplane wheels to fly, not to taxi around, but taxi it On the other hand, the gyroplane are often looked upon as a necessary must. The wheels don’t have to be able with its free-spinning rotor needs a evil. Actually, to be honest, wheels are to endure thousands of miles of road takeoff roll. The takeoff roll allows all-around seen as rather boring. There wear, but they do have to be lightweight. the gyroplane to take advantage of the aren’t too many kids going to college to Even more important, gyroplane wheels

40 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes DIRECTION OF TRAVEL TRAIL

DIRECTION OF TRAVEL NEGATIVE RAKE NO RAKE POSITIVE RAKE NEGATIVE CASTER NEUTRAL CASTER POSITIVE CASTER SWIVEL

WHEEL FORK

Caster can be affected by the rake of the fork. Positive caster is when the steering axis extends in front of the vertical. Positive caster creates a lot of align torque (the force that straightens the steering when you taxi forward), which improves straight-line stability of the gyroplane. Negative caster is when the steering axis extends behind the vertical. Aircraft do SWIVEL AXIS not use negative caster. It will lighten the steering effort, but decreases steering stability. SWIVEL RADIUS have to make the transition from rolling airplanes. The measure of the caster For smaller wheels, offsetting the rolling to flying and back to rolling again. And in this instance is the amount of the axis from the swivel axis is an effective way preferably they should make the transi- displacement or the trail. No displace- to achieve caster. tion without trying to force the gyro- ment at all would be a neutral caster. If plane off the side of the runway! somehow the wheel swings around in found in light sport aircraft, there are With so much attention being the other direction, that would be neg- definite limits to the amount of positive focused (and properly so!) on flight sta- ative caster and very unstable. A wheel caster you can achieve by just tilting the bility, ground handling may have been with neutral caster will shimmy even at pivot axis. And too much tilt can cause given short shrift. With the industry low speeds. That’s why the good folks problems of its own. and pilots beginning to understand at the grocery store invest in castering What positive caster does for the the physics of flight stability, it is time wheels that automatically pivot to a gyroplane is that it works to steer the to look at the lowly landing gear. After positive caster! front wheel back to center. The larger all, there seems to be a disturbing trend Another way to achieve caster is to the trail, the greater the centering effect. of aircraft getting involved in incidents angle the pivot axis of the wheel assem- This really helps on landing when the after executing a landing. Some of this bly. This angle is called rake. As the front wheel may not be lined up with can be addressed with training, but steering axis is tipped forward, then the direction of travel of the aircraft. As part of training is understanding the some positive caster is achieved. That’s soon as the front wheel touches down, a machine and its systems. because again the pivot axis of the properly castered nosegear will work to Lesson number one is that gyroplanes wheel assembly is forward of the turn- pull the wheel into alignment with the handle differently on the ground. This ing axis of the wheel. In this case the direction of travel. Since presumably the generally varies make-by-make since trail is a function of the steering pivot direction of travel is directly down the often the same landing gear designs are angle from vertical and the diameter runway, this is definitely a good thing! used on similar models, even if other of the wheel. If you have a large wheel The good news is that most all things are changed. Our focus with this like those on a bicycle or motorcycle, gyroplanes have at least some positive article will be on the front gear of tricy- you can achieve a lot of trail using this caster. The bad news is that normally cle-style gyroplanes, which are far more method. But with the smaller wheels there isn’t nearly enough forward common. In tricycle-geared aircraft, the one pivoting wheel is at the nose of the aircraft. With a tailwheel aircraft, the trailing wheel is the one that pivots. Caster, Rake, and Trail The first thing to understand about front landing gear is caster. Caster can be positive, neutral, or negative. An example of positive caster can be found on the front wheels of a shopping cart. The caster is achieved using a displaced axis. The displacement is called the trail and is also a typical tailwheel design on

Photo: Cindy Peters, Illustrations: Roy Beisswenger KITPLANES May 2015 41 Tilt angle on the nosegear is defined as the angle in a vertical plane between the wheel axle and the local surface on which the tire is operating. These views from the front of the wheel show that when a wheel with rake is turned, the tilt angle increases also. The greater the rake, the greater the tilt angle effect. caster. This is clearly indicated by the between maneuverability and stability. number of gyroplanes—both modern But since most of us prefer stable land- designs and not so modern designs— ings, it is a trade-off worth making. that dart off of the runway after land- ing at higher speeds. Three Variables The questions become how much There are three variables that designers caster is enough, how do you achieve it, can use to achieve positive caster. Those and can there be too much? are: rake, wheel diameter, and offset. Before addressing those questions, All three are part of the geometry it is important to first talk about the that can increase the trail of a caster- downside to positive caster. The big- ing wheel, which is what ultimately gest downside is that as you increase improves the caster in a nosegear design. positive caster, you also increase the Rake is the most common way of amount of force needed to turn the increasing castor in bicycles, motorcy- front wheel. It is the classic tradeoff cles, and even motor vehicles like cars. Yaw angle for a wheel is defined as the It is also common in aircraft design, angle in a horizontal plane between the including gyroplanes. However, there wheel axle and a line perpendicular to are limits to how much rake you can the direction of motion of the wheel axle. introduce into wheel geometry before These views from above show a wheel with no rake in a turn. Below that is a view you start increasing side loads. of a wheel in the same turn, only with This is because as you increase rake, exaggerated rake. you also increase the tilt angle of the wheel when it is turning. Small tilt that rely on rake for caster. As the wheel angles are acceptable, but large tilt angles gets larger, the trail also increases. After introduce large side loads on the wheel, the practical limits of nosegear rake have which can actually counteract the posi- been reached, designers often use larger- tive forces of the caster. diameter wheels to increase caster. Side loads already exist on a nosegear Larger wheels are what makes wheel on touchdown if the wheel is not smaller rake angles work for automo- aligned with the runway. This force biles, motorcycles, bicycles and even is called cornering force. Even while airplane nosegear. When a tire touches the runway, there is a caster properly works to straighten the However large wheels have limits in force to the rear that acts to begin turning the wheel. But when a wheel touches wheel out, cornering force tries to pull aircraft design, too. Larger wheels typi- down and it isn’t aligned with the runway, the wheel farther into the direction the cally weigh more. And landing forces on other forces also come into play. These wheel is turned. As rake is increased, narrow and tall tires that aren’t aligned forces tend to pull the gyroplane to the the effect of cornering force can over- with the runway are extra damaging side that the wheel is already turned. Side come the self-centering effect of the because of the moment arm between the force is defined as a force in the tire foot- print parallel to the wheel axle. Cornering caster and pull a gyroplane further and surface of the tire touching the runway force is defined as the component of the faster to the side. and the axle. side force that is perpendicular to the Wheel diameter, along with rake, is Gyroplanes have another issue with direction of motion. what actually determines trail in wheels tall front tires. Taller tires usually mean

42 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes DIRECTION OF TRAVEL

Trail Increases with Wheel Size

With the same rake, caster trail can be doubled by doubling the size of the wheel. raising the center of gravity. It isn’t nec- Purchase your ticket to essarily true, but design aesthetics also the most unforgettable aviation experience. come into play. Offset works by simply moving the BUY NOW AND SAVE! wheel axle behind the steering axis with- Visit EAA.org/tickets out using rake. Offset works with wheels of all sizes, which means that it is partic- ularly well suited for the small nosewheel sizes used in gyroplanes. Another advan- tage of offset is that it works without any of the disadvantages created by rake. Putting It All Together Remember, the point of caster in the first place is to straighten out a nosewheel when it touches the runway. There are three tools in the toolbox. We already know that rake and wheel size work together to achieve trail. However, designers can also integrate offset along Copyright © 2015 EAA with rake and wheel size. This is not uncommon in aircraft design.

RAKE ANGLE

TRAIL An even better trail can be obtained by offsetting the axle from the steering axis.

KITPLANES May 2015 43 Shimmy dampers are similar to shock absorbers and are used on some aircraft to prevent shimmy.

used to steer the rudder. After all, most pilots only have two feet. This is not a problem while taxiing and not a prob- Differential braking is one way to make castered wheels steer easier. lem when flying. However, the dual purpose of the Steering Another solution is to steer by turning steering mechanism can create problems As mentioned earlier, steering a high- the front wheel, knowing that steering for a pilot during a crosswind landing castering nosewheel is more difficult is going to take more force as the caster when the direction of the rudder needs than a low-castering nosewheel. But is increased. This is the solution that is to be different from the direction of the there are ways to get the job done. used by a lot of gyroplane manufactur- runway and the front wheel. One solution to steering a gyro- ers. The differences lie in how much This is where a significant positive plane with a lot of caster is to allow the caster is designed into the front wheel. caster shines. At the moment of touch- nosewheel to freely caster and steer with An analogy for motorcyclists is the down, it becomes more important to differential braking. This is again simi- rake of the front fork. Generally, the have a front wheel rolling straight down lar to a shopping cart or many tailwheel greater the angle of the front fork of the the runway than anything a rudder can airplanes. Instead of incorporating any chopper, the more stable the freeway do. A positive caster allows the runway kind of steering mechanism to the cast- ride. However, what comes along with to grab the front tire and straighten it ering wheel, the pilot just pushes on one that is a more difficult time turning and out as soon as the wheel touches down. side of the aircraft and pulls on the other cornering. European and Japanese bikes The greater the caster, the greater the to make it turn. value cornering more, so you generally effect. So, for a manufacturer who wants Of course the placement of the push see less caster. Luckily with a gyroplane, to design an aircraft that is controllable (prop thrust) can’t be changed, so steer- pilots aren’t as concerned about corner- at different touchdown speeds, this is a ing is accomplished by slowing one ing abilities, well, at least while taxiing. big advantage. wheel down by braking and allowing Ultimately, some designers want to the other wheel to turn. The moment make the ground steering manageable Shimmy created between the pushing on the while incorporating as much caster Front wheel shimmy is an unfortunate center of the aircraft and the pulling of as possible. But it isn’t just about the byproduct of a steerable nosewheel. the brake on one wheel usually has little strength of the pilot. Steering assemblies Everyone has had the unfortunate problem overcoming any caster. have to be strong enough to take the experience of pushing around a shop- This method requires two separate higher turning inputs from the pilots. ping cart with a shimmying wheel. braking systems (since presumably you That experience is annoying, but not want to turn leftand right, as well as Dual Purpose dangerous. On the other hand, a shim- slow down), along with the expense and For most gyroplanes using a steerable mying nosewheel can be damaging to mechanical complication that comes with nosewheel, that nosewheel is steered the entire airframe since it is a violent such a system. However, it is very effective. using the same foot pedals that are form of vibration, akin to flutter in

44 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes flight controls. Like flutter, it may only appear at higher speeds. Also like flut- ter, it should not be accepted as normal. Shimmy prevention is part good design and part good maintenance. Steering and the wheel itself should be tight, with no undamped movement (other than rolling of course!). Damping can be achieved in a lot of different ways. Friction can be used as a damper and there are even specific shimmying damp- ers, which are similar to shock absorbers and are used in some applications. From a pilot’s point of view, it is important to know that shimmy is just not acceptable. Issues for Builders It is important for homebuilders, and even manufacturers, to focus design con- cern on the undercarriage of gyroplanes. No matter how well an aircraft flies, they all have to land regularly. Mak- ing that landing a stress-free event for both the aircraft and for the pilot is important. Many nosewheel designs are simply not up to the task, and that is something that manufacturers should address. Issues for Students and Instructors The main thing here is to know your aircraft. If you are shopping for an aircraft, take into account how it taxis and how it transitions from flight to landing. If the design is not optimum, you are simply going to have to increase your skill set. A workaround for gyroplanes with little caster is to land at very low speeds and to avoid crosswind situations as much as possible. Instructors have a bigger challenge, as should be expected. Not only do instruc- tors have to understand their train- ing aircraft, they should educate their students on the differences in landing gear. This is especially important if the student is planning to transition to a dif- ferent model of gyroplane than the one being used as a trainer. Wheels may have been around for over 5,000 years, but that doesn’t mean that they are any less important or should be taken for granted. J

KITPLANES May 2015 45 maintenance matters Spark plugs: A window into how your engine is running. Spark plugs can tell an operator much Champion distributes a publication stands for a 5/8-inch 24 thread on the bar- about how an engine is running. In return called Aviation Service Manual AV6-R rel, the M stands for ½-inch reach (length they need some regular care to keep that explains their numbering system of threads into the cylinder head), 38 them working well. They are at the work- and contains much useful information is the heat range, and finally the last E ing end of the ignition system that will about their spark plugs and oil filters. It stands for two massive electrodes. A include magnetos or electronic ignition is usually available for free at any airshow higher heat range number would be a systems, wires, and the plugs themselves. where Champion is present, or they hotter plug, and a lower number would Plugs get blamed for many problems, but will send it to you if you contact them. be colder. If the last E were an S, it would they often only provide the visible indica- The main thing to remember is to run be a fine-wire or iridium plug, and if tion of a problem, rather than cause it. the recommended spark plug in your it had BY at the end instead of E or S it engine. Using spark plugs of different would be a massive electrode plug with Types of Spark Plugs heat ranges or thread lengths can cause an extended core nose. Most aviation spark plugs have 18mm problems, some of them serious. Tempest uses the same numbering threads that screw into the cylinder A common plug type is Champion’s system except their numbers have a U heads, although some come with 14mm REM38E. The R stands for resistor, the E added at the beginning. Thus a Tempest threads, a size more common in auto- motive spark plugs. The use of actual automotive spark plugs that thread into adapters as parts of electronic ignitions by companies such as Light Speed, E-Mag, and others is becoming much more common in the Experimen- tal world. These plugs are constructed somewhat differently than aviation spark plugs and are much less expen- sive. Auto plugs are preferred by elec- tronic ignition makers because of their ability to run at wider gaps and thus handle higher voltages. Among aviation spark plugs there are massive electrode plugs (most com- mon), extended reach (a type of mas- sive electrode plug), and fine-wire or iridium. Plugs are further distinguished This combination spark plug tester and cleaner by Aircraft Tool Specialties runs about by how long the threaded portion is $600. It uses compressed air from your shop compressor to test the spark plugs under (reach), heat range, and the threads on pressure. This is considered the definitive test of whether or not a plug is good. The the barrel (where the plug wire attaches). plug cleaner portion is on left.

Dave Prizio is a Southern California native who has been plying the skies of the L.A. basin and beyond since 1973. Born into a family of builders, it was only natural that he would make his living as a contractor and spend his leisure time building airplanes. He has so far completed three—a GlaStar, a Glasair Sportsman, and a Texas Sport Cub—and he is helping a friend Dave Prizio build a fourth, an RV-8. When he isn’t building something, he likes to share his love of aviation with others by flying Young Eagles or volunteering as an EAA Technical Counselor. He is also a member of the EAA Homebuilt Aircraft Council.

46 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes Massive electrode plugs are best gapped with this special tool available from many Mechanic Ed Zaleski uses a Champion plug Massive electrode aviation spark plugs. aviation vendors. The screw device on the gap gauge to set the gap on a spark plug. The standard plug is on the right and the top presses the ground electrode closer to extended nose ‘BY’ plug is on the left. the positive electrode.

UREM38E is equivalent to Champion damage. A word to the wise: place some- recognize this as a valid test, saying that REM38E. Of course, both manufacturers thing soft under your engine when you the resistors in their plugs are voltage insist that their plugs are better than, are removing your plugs, especially irid- dependent. That means that a resistance rather than equivalent to, the other ium plugs, just in case you get a case of reading at the voltage a typical multi- brand. I’ve had good luck with both the butter fingers. It is a bitter pill to swal- meter would provide is not the same as brands, the main difference being the low to throw away an iridium plug ($70 the 10–20,000 volts an ignition system cost advantage held by Tempest. to $95 each) just because you dropped it. would make. Unfortunately Champion’s Needless to say, if your plugs are not spark plug tester and cleaner costs $1,790 Maintenance Time firing well, even after cleaning, no mat- retail. Even a low-cost copy costs about Spark plugs should be cleaned and ter what the wear, it is time for new ones. $600. Unless you have a shop where you gapped at each yearly condition inspec- A spark plug tester that places the plug are cleaning and testing plugs all the tion or every 100 hours if you are fortu- under pressure is the best way to test a time, the ohmmeter test will have to do. nate enough to fly more than 100 hours plug, but a cheaper way is to measure the Spark plugs clean up nicely with media per year. They should also be checked resistance through the center electrode blasting, either in a blast cabinet or by whenever you fail to get a good mag with a standard ohmmeter. Any plug using one of the popular cleaning and check during runup. Plugs should be with resistance over 5000 ohms should testing units available from your favorite replaced when half or more of the elec- be replaced according to Tempest, with aviation parts and tools vendor. The main trode has been worn away by sparking 1000–1500 ohms being common read- thing to remember with media blasting and corrosive combustion gasses. An ings for good plugs. Champion does not is to take it easy. Excessive blasting will easy way to see this with a massive elec- trode plug is to note the oval shape of the center electrode. When the oval is half as wide as it is long, it is time for a new plug. You can also buy a gauge that will take any guesswork out of the pro- cess. With a fine-wire or iridium plug, it is time for a replacement when the wire is worn halfway through or more. BY plugs are finished when the ground electrodes are worn to a knife-edge point and the center electrode has a noticeable wear ring below the tip. Plugs should also be replaced if a cen- ter electrode insulator is cracked or after they have been dropped on a hard sur- face, which may cause internal insulator Normal spark plugs recently removed from a smoothly running engine.

Photos: Dave Prizio and courtesy of Champion Aerospace KITPLANES May 2015 47 erode the insulator around the center electrode, leading to premature failure. The best way to measure the spark plug gap is to use a wire-type spark plug gauge such as the Champion CT-450 or a similar one by ATS. Most aviation spark plugs should have a gap of somewhere between .016 and .021 inches. Thus the .015 wire should fit between the ground and center elec- trodes, but the .022 wire should not. Be sure to consult your plug manufac- turer’s literature for the correct gap for your engine and spark plugs. The Champion Aerospace Aviation Catalog AV-14 has an extensive table showing spark plug gaps. It is available online at: An array of tools and materials needed to service spark plugs. Included are: spark plug tray, www.championaerospace.com/assets/ torque wrench with plug socket, spark plug anti-seize compound, fine-wire plug-gapping AV-14-Jan2010.pdf or in paper form tool, copper spark plug gaskets, spark plug gap gauge, and a massive electrode gapping tool. through Champion or Amazon. Do not use machinists’ flat feeler gauges to gap that make the process better than just With all the plugs out, it is time to look massive electrode spark plugs because grabbing a wrench and taking the plug things over and see what’s happening in of the curved gaps they employ. out. It is common for a little dirt and each cylinder. Plugs should be a caramel Champion and ATS make special tools debris to collect around the base of color with the edges often somewhat for adjusting spark plug gaps. While it the top plugs, so a little squirt of com- darker than the tips. There should be is possible to adjust gaps with ordinary pressed air can help to remove this no signs of oil, lead, or carbon fouling, tools, it is not a good idea, because material and keep it out of your engine. no cracked electrodes, and no excessive it is very easy to damage plugs with When removing the plug wire, you typi- gaps between the center and ground improper tools and techniques. Fine cally use a ¾-inch wrench to loosen the electrodes. What is more common in wire plugs are especially prone to dam- cap, but if you take the time to also grab the real world is that some plugs will age from improper gapping due to the a 7/16-inch wrench and hold the center show signs of carbon or oil fouling and brittleness of iridium used in their elec- portion, you will save some wear and others will look pretty good. Some or trodes. Aircraft Spruce and other aviation tear on the wires. A spark plug tray is a all plugs may show signs of lead accu- vendors have spark plug gapping tools must for keeping track of which plug mulation down inside the plug between starting at around $10. came out of which cylinder. This is the center insulator and the body of the important because plugs need to be plug. You will have to decide how much Changing and Reading Plugs rotated at each changing to even out of each of these problems you are will- Removing spark plugs is simple enough, the wear caused by different polarities ing to live with. Less is better, but as an but there are a few steps you can take in the ignition system. engine ages, it is pretty common to see

These plugs show signs of lead fouling. Note the tiny balls of lead These plugs are oil fouled. It is pretty obvious when plugs are inside the plug between the body and the insulator. A dental pick oil fouled because they are oily. It is less obvious what should is the best tool for removing lead balls such as these. be done about it.

48 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes A mechanic uses a dental pick to remove lead from a spark plug. Carefully pick out lead fouling and never try to remove lead with just blast cleaning. more and more of these things show lighter and cleaner than more traditional up on your spark plugs. Lead fouling is rich-of-peak operation. Excessively rich almost a universal problem unless you running can cause carbon build-up in have access to unleaded auto gas with- the cylinders and contribute to sticking out ethanol. Few people are so fortunate. valves, in addition to simply wasting fuel. Carbon fouling is a sign of running For these reasons it should be avoided. too rich. Aggressive leaning will usually Oil fouling is more common on older cure this problem completely, unless engines and especially on the bottom the plug is simply not firing well. With plugs. It is caused by oil getting into the a carburetor, where even exhaust gas cylinders through worn rings and cyl- temperatures are difficult to achieve, it inder walls. It can also come in through may not be possible to cure the prob- worn intake valve guides. The only sure lem 100%, but aggressive leaning dur- cure for this is to overhaul the offend- ing taxiing and proper leaning in cruise ing cylinder, but if the engine is running will help a lot. Running lean-of-peak will well and plug fouling is manageable, it usually produce a spark plug color that is may be acceptable to wait until it gets

This plug shows 1446 ohms resistance through the positive electrode using a standard multimeter. This is well within the acceptable range. Plugs with more than 5000 ohms resistance should be replaced according to Tempest.

KITPLANES May 2015 49 These plug wires show signs of deterioration from years of service and possibly some not-too-careful plug cap removal. This chart shows Champion’s recommended rotation for spark plugs in four- and six- new copper gaskets. These gaskets are Mag Check cylinder engines to minimize the effects of inexpensive, so get a bag of them and The mag check during runup is the stan- polarity on the spark plug wear patterns. store them with your spark plug tools. dard test in the field for spark plug perfor- worse. If you are really worried, a bore- Champion says that annealing will not mance. After all, no matter what the plugs scope examination is the next step. With fully restore these gaskets, so it is best to look like or how they test on the bench, that information you will be able to make just toss them out after they have been if they don’t work during a mag check, a better decision. This becomes a judg- used. Plus, threads need to be treated their performance is simply unacceptable. ment call that you must make yourself. with anti-seize compound before instal- However, not all poor mag checks come A consultation with a trusted mechanic lation. Do not forget this important step. from bad plugs. As the name implies, a may be in order. The spark plug can tell A seized spark plug can be a real head- mag check is also a test of the magnetos. you about the problem, but obviously, a ache to remove and potentially damage If your mags are approaching or past 500 clean plug will not cure it. your cylinder head. With anti-seize and hours since their last inspection and/or Lead fouling will be with us until we a new gasket in place, the plug should overhaul, you may well have a magneto get lead out of aviation gasoline. Little be threaded by hand into the head. If it problem that no amount of new spark balls of lead can short out plugs and does not go in easily remove it and find plugs will cure. Get out your logbook and cause them to fail. It is best to remove out why. The threads on the plug and in see when your magnetos were last ser- these lead deposits with a dental pick the cylinder head need to be clean and viced or replaced. It may be time to pull that will fit down into the tight space undamaged. You can use a small trian- them off and give them the once-over. between the center insulator and the gular file to touch up the threads on a Minor magneto work such as replac- plug body. Carefully pick out each piece spark plug, but you will need a thread ing the points and condenser, and set- and then blast the plug clean. Do not try chasing tool to clean up cylinder head ting the internal timing are well within to remove lead fouling by blasting alone. threads. The thread chasing tool is much the capabilities of most amateur build- If lead fouling becomes a real nuisance, preferred over a machinist’s tap for this ers and can be done without a lot of a switch to extended-nose BY plugs may work. The idea is to simply straighten out expensive special tools, but more seri- provide some relief. Your dentist will damaged threads, not cut new ones. If ous work will be easier to pass off to a often have used picks that will work for spark plug threads are extensively dam- repair station. you but are no longer suitable for his aged, you will need to get a new spark A multi-cylinder EGT is a great way work. That can be the silver lining in your plug. If cylinder heads will not clean to track down a spark plug or plug wire next teeth cleaning experience. up with a thread chaser, you will need problem. When you do your mag check, some professional help. In any case, do note the EGTs for each cylinder. A misfir- Installation not force a spark plug into your cylinder ing cylinder will have a lower EGT than Once the plugs are properly cleaned and head. Fix what you can, but also have the the rest. That will save you removing gapped, it is time to reinstall them. Every good judgment to know when the prob- and checking all your plugs. By switch- time spark plugs are changed they need lem is bigger than your ability to solve it. ing from one mag to the other, you can

50 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes If a spark plug will not easily thread into the cylinder head, it may help to restore the threads in the cylinder head with a spark plug thread chasing tool. This is much preferred over a standard tap. pin the problem down to one spark plug fairly easily. Plug wires do not often go bad, but they can. If you have a weak cylinder, but the plugs check out fine, you have two options. Switch the plug you suspect with one that you know is good. If the prob- lem follows the spark plug, you know you have a bad plug. If the problem remains, you most likely have a bad plug wire. You can also measure the resistance of several wires and see if one of them has much higher resistance than the others. If it does, it probably needs to be replaced. Don’t forget that other things unre- lated to the ignition system can also cause a cylinder to run poorly. Clogged injec- tors, burnt or sticking valves, and intake tract leaks are other possible culprits, but those are topics for other articles. J

For more information see: Champion Aerospace Spark Plugs http://tinyurl.com/cd8j6wg Champion publications: Aviation Service Manual AV6-R and Aviation catalog AV-14

Tempest Aviation Spark Plugs http://tinyurl.com/lr95gvp Tempest Aviation Spark Application Guide: http://tinyurl.com/l9ddm6z

KITPLANES May 2015 51 The Dawn Patrol “Was he packin’ heat?” It had started out as a typical July day “Did he have an earpiece and was he Landing International Airport and get us at Liberty Landing International Airport. talking to other people?” all in a dither, we wanted him to look the The normal Missouri mind-numbing, “Nope.” part. We wanted the whole nine yards. We high-humidity summer heat had settled “Did he act mean and menacing?” wanted drama. We wanted intimidation! in. The airport had been deserted except “Nope.” We wanted the proverbial man in black. for Big Bad Bob Loyd. He was semi-doz- “Well…how did you know he was who We wanted a big guy with wide shoulders, ing, sacked out on the ratty old moth- he said he was?” narrow hips, and standing about six-four eaten couch in his hangar, listening to “Well…he had this very impressive weighing in at a lean and mean 240. We the radio. Bob was taking a break from badge he showed me.” Bob replied, “It wanted a black suit with a bulge over the replacing the burned front piston on the said U. S. Secret Service.” left breast pocket. Where was the throat Rotax 582 on his Avid Flyer “A” model. Bob was getting frustrated at all the mic with earpiece? We wanted a stern no- Then a strange car pulled into the shouted questions. nonsense face, firm chin and steely blue airport. The car drove around ’til the “You mean he wasn’t wearing black, eyes hiding behind mirrored sunglasses. driver found Bob’s open hangar. The car didn’t have shiny sunglasses, wasn’t car- This was a rip-off. We wanted Jack Reacher! stopped. A stranger got out and looked rying heat, didn’t have an earpiece radio, The questioning continued. “Well, around. Then he went into Bob’s lair. but he was an actual, real U.S. Govern- why was he here?” Now, we need to jump ahead about ment Secret Service Agent? Then Bob dropped the bomb. “He three hours. That’s when the rest of the “Yep…that was it.” was here to give us a copy of the NOTAM usual mob of airport bums descended Well…Hell! We was robbed! If a secret (Notice To Airmen) about the upcom- on the airport to find Bob in a jumping- service agent was going to come to Liberty ing visit of the president; he’s getting in up-and-down state of agitation. This set into motion a unique, never-happened- before, out-of-the-ordinary event that sent Liberty Landing International Air- port into a state of turmoil. It wasn’t quite pandelirium, but it was dang close. The excited airport bums surrounding Big Bad Bob were all shouting questions at him faster than he could answer them. “Was he packin’ heat?” someone asked. “Not that I could see.” “Not even in a shoulder holster?” “Nope, he wasn’t in a suit.” “You’re kidding…He wasn’t in a black suit? ” “Nope. He was just dressed like a normal guy. He was in slacks and a sport shirt.” “Was he wearing mirrored sunglasses?” Sharon removes a spark plug from one of the two cylinders on her Valley Engineering “No.” Big Bad Twin.

has written two books about the joy of flying; “You Want To Build And Fly A What?” and “Fokkers At Six O’clock!!” He was the recipient of Flying’s 2001 Bax Seat Award “for perpetu- ating the Gordon Baxter tradition of communicating the excitement and romance of flight.” Dick Starks Dick and his wife, Sharon, both fly WW-I replica aircraft.

52 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes per hour. (’Course, 60 mph is our actual groundspeed on a hot, high-humidity, zero-wind day.) Some days we’d actu- ally get some limited air time in, just as the sun was going down. On those days, about sundown, the designated “bump dummy” was called on about every twenty minutes to take a trip around the patch to see if the bumps were dying down. It only took 15 minutes some days to go from bouncing-your- guts-out to silky smooth. Some days, the bumps never did go away. On those days we’d all put the birds away and go home to sulk. Besides that, flying on a hot, high- humidity day is hard on planes, engines, and pilots. On some days, the higher we Jerry (The Rotaxman) Sharp traces down an electrical problem on Vernon Petre’s went, the hotter it got. The hotter it got, Quicksilver MX. the bumpier it got. On those days, the here about 6:30 tomorrow and is leav- flying for 24 hours starting at 6:30 p.m. realization that this is a hobby was really ing about 6:30 the next day. The bot- the next day. brought home. Finally deciding to give it tom line is, from 6:30 tomorrow night till Well…poop! That dropped a big black up, quit, and go home is the best option he leaves nothing can be in the air. No cloud of gloom over everyone. The next you have. On those days, getting in the planes, choppers, drones, any kind of RC day was forecast to be one of the best days air-conditioned car for the sullen drive aircraft, balloons, model rockets, … for flying we’d had in over two months. home was a blessed event. nothing goes in the air.” The typical Missouri summer had The day the NOTAM was scheduled to I asked, “And that was it? He didn’t do kicked in with stunning impact. We go into effect, we were all out at the field anything else?” were experiencing days of mind-numb- flying at 3 p.m. We were trying to get in “Nope…he said, ‘Have a nice day,’ got ing heat, wet-wool-blanket humid- as much airtime as we could before the in his car, and left.” ity, and spar-bending, wire-twanging NOTAM’s hammer dropped. It was nice “Did you say anything to him concern- thermals during the day. This made and cool with winds zero, gusting to two. ing politics?” Now, this was a loaded flying our lightweight little WW-I repli- So even this early in the afternoon, it question. Bob is a U.S. Army vet and cas seem like you were driving your car wasn’t that bad. Scattered bumps aside, his political viewpoints (like just about over a freshly plowed field at 60 miles it was perfect WW-I flying weather. everyone at the airport) run about five miles to the right of Attila the Hun. “Nope,” Bob said. “I bit my lips till they bled but kept my mouth shut.” There was a big sigh of relief from all of us. We’d really miss Bob. We all gathered around the big table in the back of the hangar and tried to make sense out of the NOTAM. We were looking for some kinda loophole, so we could get some flying in. The NOTAM’s map was filled with different interlocking colored circles that covered the entire Kansas City area. There were different times noted for each circle when the president was going to be in different areas of the city. Unfortunately, our little airport Vernon Petre took over while Jerry went to his house to try and find a part. Vernon is a was inside every one of those circles. very good mechanic, too. But, the care and feeding of a Rotax is The Rotaxman’s specialty. Consensus: We weren’t going to do any We all defer to him concerning those frustrating beasts.

Photos: Dick Starks KITPLANES May 2015 53 Some bitterness became apparent as the shut-em-down time approached— the flying was just too great to quit! Vernon Petre flew in with his Quicksilver MX from his little 600-foot strip about two miles away to get in on some of the action, too. About 5:30 he got ready to fly back to his field, and his engine wouldn’t start. We were frantically taking turns yanking on his engine’s starter rope, try- ing to get that obstinate little so-and-so to run. Time was growing short! Many new words were tried out, but none of them convinced the recalcitrant little engine to start. Dave Laur brushes the final coat of red on the right upper wing’s roundel of his Graham Six-fifteen rolled around, so we just Lee Nieuport 16. made room in the hangar for Vern’s bird, pushed it in, and went home. Vernon’s Next, she was going to change the was getting on her nerves. Pretty soon wife Carol drove over and took him back spark plugs on her Morane’s Big Bad her left eyelid started to twitch. Sharon’s home. We’d have all day tomorrow to Twin 48-hp engine. Pretty soon the fuse finally burned out. She yelled some fight with the engine and try to figure usual semicircle of chairs occupied by rude new words at us. Most of us chose out its problem. an avid group of airport bums with the safer, prudent route and went to do So, what did we do on a perfect flying nothing else to do was watching her something else, far away from her glare. day when we couldn’t fly? We still went while she toiled away. While she was Only Fred Porter, the sweetest guy at to the airport to sniff around. There was toiling away doing all this, they offered the field, stayed to help her out. Fred- hangar talk flowing like a turgid stream scintillating educational commentary die’s our big teddy bear, and no one’s with the rest of the airport bums. After as she was talked through removing, ever going to be mean to Fred. He was a while even this got boring, so some cleaning, changing (if needed), gap- safe entering the red-tinged force field of us decided to do some past-due air- ping, applying anti-seize compound to shimmering around Sharon. craft maintenance. the threads, and reinstalling the new I adjusted the brake cables on her Morane Sharon cleaned all the bird poo off spark plugs in the engine. I don’t think and my replica Graham Lee Nieuport 11. her Airdrome Aeroplanes replica 1915 our commentary was helping much. I Dick Lemons installed disk brakes on Morane-Saulnier’s wings, fuselage, and guess getting contradicting opinions his Airdrome Aeroplanes Fokker E-III. tail feathers. Then she washed it and did from six different sources all at the same He also adjusted the belt tension on his some touch-up painting. time on how to do what she was doing Valley Engineering Series 3 PSRU on

Sharon’s Morane is ready for a “smoke test” where we start it up and check for any leaks, seepages, or problems before the final buttoning up.

54 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes Dick Lemons works on installing the brakes on his Airdrome While Mary Batson and Sharon watch, Big Bad Bob gets ready to Aeroplanes Fokker E-III replica. replace the front piston on his Rotax 582. the Big Bad Twin engine he had in his Two-Cycle Engine Toss,” KITPLANES®, Vern’s engine transformed from a sul- Fokker E-III. October 1997.) len lump of inert metal into a scream- I changed the oil and installed new And, the engine that got the heave- ing fire-breathing beast. It was starting spark plugs in my Nieuport 11. ho was one of Jerry’s engines. It had on the first pull, running about 800 rpm Mark Pierce was tracking down a small failed on him at least eight times with more than usual, and Vernon was one fuel leak in a fuel valve on his 1945 Piper no warning and displayed no symptoms happy camper. The Rotaxman had tri- L-4 Liaison. when it was back on the ground. Now, umphed again. As usual with most Dave Laur was painting the roundels Jerry’s got a fuse about 1/16-inch long, two-stroke engine issues, there were on his recovered Graham Lee Nieuport impregnated with fulminate of mercury. multiple problems with the engine. In 16’s wing. When it finally burns out, the results Vernon’s case there were four different Other should-be-done stuff that had are instantaneous, educational, and things wrong at the same time. Fixing been put off because of the previous unbelievably entertaining. Since the one problem did not mean the engine heat and humidity was done on some word has been spread worldwide about was finally going to run. It just took a other planes. Jerry’s unbroken Olympic record in the whole day to track down all the engine’s Some guys with FAA repairman cer- two-cycle engine toss, other frustrated ills and get them dialed in. tificates did their Experimental aircraft’s two-stroke flyers have found their way The president finally left town in annual airworthiness condition inspec- to the airport just to stop by and shake Air Force One. When he was out of the tions, even if they weren’t due for a few Jerry’s hand. NOTAM’s airspace and it was cancelled, months. Good cool July weather in Mis- The NOTAM lasted for the full 24 we hit the sky. The good flying weather souri isn’t to be wasted. hours. That was a good thing ’cause continued for the rest of the week. We But the real drama was with the Rotax that’s how long it took to fix Vernon’s got a lot of flying in. engine on Vernon’s Quicksilver MX. A engine. Jerry, using some words none One last note, Tom Glaeser, our resi- specialist was required, and at Liberty of us had ever heard before, finally got dent pusher of the envelope, wanted Landing International Airport, we hap- pen to have just the man we needed liv- ing on the field. Yes-sirree-Bob, we’ve got “The Rotaxman,” Jerry Sharp. Jerry’s saved us on our Kolb Twinstar with its tem- peramental Rotax 503 many times. (The Kolb now has a Valley Engineering Big Bad Twin four-stroke muttering happily away, and it’s just what we needed.) Anyway, if Jerry can’t fix any ailing two- stroke engine, a Herculean heave off a bridge into the mighty Missouri River is in order. It’s only happened once in over 26 years of flying at LLIA. (See “The

KITPLANES May 2015 55 Airdrome Aeroplanes www.airdromeaeroplanes.com/ Avid Aircraft www.avidflyeraircraft.com/avid. php Culver Props/Valley Engineering LLC www.culverprops.com/ Dick Starks books on Amazon www.amazon.com/ (books, Dick Starks) Graham Lee Nieuport plans http://nieuports.com/ Hirth Aircraft Engines www.recpower.com/ With the NOTAM cancelled, Sweetie and I make a pass down the runway at Liberty Jack Reacher Series by Landing International Airport after a successful bit of maintenance. Lee Child www.leechild.com/ to get out on the runway during the well-armed Apache helicopters prob- Kolb Aircraft NOTAM and just run up and down with ably hiding just over the horizon. www.kolbaircraft.com/ just one wheel off the ground. He’s got Thankfully, that adventure didn’t happen. Quicksilver Aircraft the name on his plane, “le rebelle sans Because it looked like we would prob- http://quicksilveraircraft.com/ idée,” for a reason. (It loosely translates ably be in for another brutal Missouri to “The Rebel Without A Clue.”) winter, we got in as much flying as pos- Rotax Engines www.flyrotax.com/home.aspx We talked him out of it finally when we sible ’til the first snow flew. And then told him about the lookdown capability we hunkered down to see what winter The Kansas City Dawn Patrol www.kcdawnpatrol.org/ of the radar in the circling unseen F-16s would bring. index.php lurking high up there in the sky, and the The adventure continues… J Easier Panel Wiring SHOP By David Boeshaar TIPS

Building a multi-part panel allows for easier maintenance and changes later on. You can remove a few screws and pull just the section of panel you need to work on. To accomplish this, you need to make sure there is enough slack in all the wires to move the panels out. Even one wire that’s too short will To make wiring easier, temporary brackets Wiring each section away from the panel cause headaches. hold the left and right sections of this frame ensures that all wires will be long instrument panel a few inches in front of enough to make it easy to remove the sec- To speed up the wiring process and the actual panel frame. tions for future maintenance. prevent short wires, build some tempo- rary support brackets to hold the panel angle that has been cut to length and The temporary brackets also make it far enough away from its frame that it drilled for Clecoes to fasten into place. easier to bundle and anchor wires for a will be easy to remove the panel later. Precise measurements aren’t required— nice clean job before reattaching the You can make the brackets from scrap just eyeball it. panels to the frame. J

56 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes Risky Business Distractions: Stay focused in the air and the hangar. I could have kicked myself. Punching Mindlessly, I kept one eye locked onto she was quite easy on the eyes, but a hole into my RV-7A horizontal stabilizer the dimpling job, but I just couldn’t because the scene graphically illus- skin where a hole didn’t belong—how help but divide my attention with the trates a distraction’s hidden hazards at careless of me! I knew it was my fault, airshow outside. Punch! critical moments. although it would have been easy to I pressed the DRDT-2 handle down Air Force mishap investigators assign blame the F-22 demonstration pilot prac- with the dimple nipple not quite distraction to an accident’s list of factors ticing just outside my door. aligned with the rivet hole, making a when the individual suffers an interrup- I was in my shop, a carport/base- perfectly dimpled hole right next to tion of attention, or inappropriate redi- ment beneath my officers’ quarters where it should be, but precisely where rection of attention, by an environmental (aka “house”) at Langley Air Force Base, it didn’t belong. Insert Spock’s colorful cue or mental process that degrades dimpling my horizontal stabilizer skin metaphor here. performance. In other words, something with my DRDT-2. Ah, the DRDT-2…that’s How could I have pulled this bone- took their eye off the ball. In the Depart- another one of those great tools that I head maneuver? ment of Defense Human Factors Analysis love because it makes short work out of and Classification System (DoD HFACS), dimpling large sheets of Alclad. My shop Distraction: The Most Basic distraction falls under the Cognitive Fac- door faced north, directly toward the Human Factor tors category of mishap human factors if center of Langley’s airfield environment Remember the woman in the red dress cognitive or attention management con- only a quarter of a mile away, giving me in the movie, The Matrix? Our hero Neo ditions affect the perception or perfor- a great view of the F-22 demo team’s was undergoing his training under mance of individuals and result in human practice sortie. Morpheus, who used the lovely lady to error or an unsafe situation. I’m cruising through the dimple distract Neo’s attention long enough I buy that completely because that red process when the Raptor roared into to introduce him to the dangerous dress definitely impacts Neo’s attention the vertical and “hung on the blades” agents. As an aviation safety pro, I love management. “Are you listening to me, midair, blasting the sound of freedom. that movie scene, not only because Neo? Or were you looking at the woman

Elephant Walk—an F-16 four-ship taxis toward the runway. In a similar four-ship, the number 4 wingman got distracted while typing information into his aircraft computers and taxied into his element leader’s aircraft. (Photo courtesy of U.S. Air Force)

Sid “Scroll” Mayeux has over 25 years of experience in aviation training, safety, and risk management in the military, civilian, airline, and general aviation sectors. He cur- Sidney Mayeux rently trains Boeing 777 pilots, and he is building a Van’s RV-7A.

Photos: Sid Mayeux KITPLANES May 2015 57 in the red dress?” Cue the agent with the giant pistol. Any interruption to an established task flow constitutes a distraction. One cold January day in Florida (they do happen, I’m told…but don’t let that dis- tract you), an RV-6A pilot was only a few miles out from his home ’drome, knock- ing out his landing checklist. However, several ATC vectors and his airspeed management efforts distracted him so much that he missed the checklist step for engaging the carburetor heat. His ILS approach went well until about 1/3 “Squirrel!” Stay focused when you’re running the drill. mile and 200 feet agl, when the engine suddenly stopped producing power. He specifically cite distraction as a factor, pilot number 4 didn’t notice that num- momentarily tried switching fuel tanks, the report’s mention of ATC vectors and ber 3 had stopped until it was far too then concentrated on flying a success- airspeed tasks represent classic distrac- late, and he taxied his jet into number ful dead-stick landing. Thankfully, he tors to his checklist efforts. 3’s tail, damaging both fighters. Nobody and his passenger walked away from was injured. the crash. Driving While Distracted In a nutshell, the Air Force Accident FAA investigators found clean fuel I know—this is an aviation magazine, so Investigation Board found that the filters, blue fuel throughout the lines, bear with me while I set this up. As of this number 4 pilot was…well, texting and and no problems with the fuel system. writing, 44 states have laws of some type driving. Those are my words, not the However, weather observations at the that prohibit texting while driving. Does Board’s, but the parallel is inescapable. time of the mishap showed conditions the same restriction exist for aircraft? It While he was taxiing, the number 4 conducive to carburetor icing. The ought to, if it doesn’t already exist in our pilot was accomplishing additional air- pilot confirmed to investigators that standard operating procedures. craft system checks and typing infor- he had not turned on carb heat for the In Korea a few years back, a four-ship mation into his ship’s computers rather approach, although he would have nor- of USAF F-16s had started engines and than concentrating on the taxi task at mally. The NTSB assigned the probable were taxiing their elephant walk out to hand. He suffered a breakdown in his cause(s) to the pilot’s failure to use car- the runway. Per normal operations, they visual scan, failing to properly monitor buretor heat in conditions conducive to stopped at a spot so an airman could his aircraft position relative to the air- carburetor icing, which resulted in loss run an electronic check of their radar craft in front of him. The Board listed of engine power and collision with trees gear. The flight lead stopped in the several human factors including task and ground during the resultant forced parking spot, and number 2 and num- misprioritization, channelized atten- landing. Although the NTSB doesn’t ber 3 stopped behind him. However, tion, and distraction. Now, I have two really slick 10-inch Dynon SkyView EFIS screens waiting for their chance to dazzle me on my RV-7A’s first flights. As I consider this F-16 acci- dent, I can’t help but think: There, but by the grace of God, go I. In the spirit of the sterile cockpit, I must set myself some standard operating procedural rules regarding when I will (and will not) go heads-down to type stuff into my Sky- View. The distraction hazard is clearly there—time to devise ways to manage it.

Distractions and the Knock-It-Off Call Aftermath of an RV-6A lost to distraction. The engine failed in the pattern due to carbu- A few months ago you and I hangar- retor ice when the pilot forgot the carb heat. ATC vectors interrupted his checklist flow. talked the knock-it-off call. In a nutshell, (Photo courtesy of Daniel L. White) if you’re doing something, and it isn’t

58 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes going right, just stop doing it…call and investigator said that the pilot’s diverted to (hopefully) hide my mistake once execute a knock-it-off. Distractions are attention (distraction) contributed to his it’s painted. tailor-made for the knock-it-off. improper flare and his failure to recover However, I also learned that there is In another Experimental aircraft acci- from the bounced landing. definitely such a thing as “a bad time” to dent, the pilot was on downwind to Once you notice you have somehow work on the airplane. Since distraction is land on a 4,300-foot runway when he diverted your attention onto anything such a risky endeavor even to kitbuilding, noticed he couldn’t lift the flap handle other than the task or checklist at hand, I now manage that risk by never building beyond the half-flap setting. While still you really should stop, step back, and when some overwhelming distraction is on downwind investigating the prob- reset the activity. You know…call a knock- present. Building—and flying—an air- lem, he found that the seat belt had it-off. That applies both in the air, in the craft requires dedicated mental atten- wrapped around the flap handle, gum- hangar, and in the shop. Did you forget to tion. If something prevents me from ming up the motion. He released his slip the shrink tube onto the wire before concentrating completely on my work, seat belt to free the flap handle; how- crimping the terminal connector? Did you then the work needs to stop unti… ever, now distracted by the seat belt, he remember to sand the surface of that fair- ….sorry. My wife is calling me… J had dropped his airspeed control out of ing before mixing and applying the flox his crosscheck. and epoxy? Where is your tow bar; still on Note: All references to actual crashes are On his downwind-to-final turn, the the nose/tailwheel? based on official final publically-released RV-6A was 15 mph fast and high, but the So, as for me and my stabilizer skin, NTSB and Air Force Accident Investiga- pilot figured the 4,300-foot runway was I carefully flattened out the dimple on tion Board reports of the accidents, and long enough to fix it, so he proceeded that bad hole and redrilled it to #40 to are intended to draw applicable aviation with the approach. He leveled into the remove any edge crack. I measured its safety lessons from details, analysis, and flare fast, but the airplane landed hard edge distance from the correct hole: conclusions contained in those reports. It and bounced three times. The A-model It’s good, well enough away to avoid a is not our intent to deliberate the causes, RV’s nosewheel folded on the third crack. After dimpling the correct hole, judge or reach any definitive conclusions bounce, and the airplane nosed over. In then riveting and completing the stab, about the ability or capacity of any person, his final causal determination, the NTSB I filled the bad hole with epoxy sealant living or dead, or any aircraft or accessory. Kitplanes subscriber alert! several of our Kitplanes subscribers have received what appear to be “renewal notices” or “automatic renewal notices” from a company known as preMier subscriptiOn serVice, 5star subscriptiOns, rapiD MaGaZine cOllectiOn, MaGaZine billinG serVices, publisHer’s billinG serVices, circulatiOn billinG center or other similar names. Addresses for these firms include Dallas, tX; lincoln, ne; Omaha, ne; san luis Obispo, ca; salt lake city, ut; White city, Or and prescott, Fl. These firms have nOt been authorized by us to sell subscriptions or renewals for Kitplanes and we cannOt Guarantee that any order or payment sent to them will be forwarded to us. Kitplanes does nOt offer a subscription term of more than 2 years, nor do we retain your bank account information. if you see an offer for 3 or more years or if you receive a notice that references your subscription anD your banking information, it is nOt an authorized offer. We urge you to report these notices to us, as well as to your state’s attorney General and better business bureau. any offer you receive that does not bear our company logo or corporate/customer service address or 800 numbers should not be considered approved by us. the only autHOriZeD inFOrMatiOn for Kitplanes is: toll free via telephone 1-800-622-1065, Dial america renewal telemarketing, or www.kitplanes.com/cs Our texas customer service center: 1-800-622-1065, pO box 8535, big sandy tX 75755 Or our corporate offices at: belvoir Media Group, llc. aviation publishing Group 535 connecticut ave norwalk ct 06854 should you have any questions at all about mail that you receive, please contact us at our web site: www.kitplanes.com/cs or call us toll free to speak to customer service.

KITPLANES May 2015 59 CHECKPOINTS Limitations. Clint Eastwood (as Dirty Harry) once Aircraft for the RV-10. Unfortunately, I corner and came out only for cutting said, “A man’s got to know his limita- was one of those who experienced the rebar or other non-skilled tasks. tions.” I think that when it comes to problem with some pretty severe crack- For years I had been promising myself building and flying airplanes nothing ing, requiring removal of the engine and I would take one of the EAA SportAir could be closer to the truth. Yet I con- engine mount so it could be properly Welding Workshops, and these two tinue to see many push the limits of repaired by—you guessed it—welding! episodes told me it was time to act. So, their knowledge and skills in both areas. I not only didn’t have the equipment, I last weekend I managed to attend the Sometimes the result is an unreliable still didn’t have the skills. So the aircraft TIG course in Griffin, Georgia, taught airplane that is a hangar queen due to was down an extra day while the mount by Scott Skrjanc of Lincoln Electric. This poor workmanship. Sometimes it can was off to the welder. In the meantime was a very intense course with only two be outright dangerous. And in too many there also appeared a crack on the pilot’s hours of lecture. The rest of the two days cases, the outcome has been an acci- side step on my RV-10. Of course, it also were spent in your own booth with all of dent with injuries or even death. needed welding. Here’s my limitations the proper tools and equipment to learn In today’s world of the Internet, the getting in the way again! A neighbor how to weld 4130, stainless steel, alumi- EAA (including local EAA Chapters), and with a TIG welder offered to repair it and I num, and chrome-moly tubing. Scott is with the proliferation of homebuilt air- watched. Boy, that sure looked easy! See, probably the Leonardo da Vinci of weld- craft throughout the world, there really in the past the only welding I had done ing. I learned many things that weekend, isn’t any excuse for not seeking help in the on 4130 steel was with a torch, and I was including two important ones: I probably areas that might push an individual’s com- real good at creating lots of holes and won’t live long enough to ever weld like fort or experience zone. To ask for help is a scrap. Sound familiar? For the last few Scott, and I probably still shouldn’t TIG sign of maturity and wisdom. Use it. years, my torch was relegated to a dusty weld on an aircraft! It sure looks easy, as

Welding Even though I have built 10 airplanes over the course of many years, there are still a few skills that I know I am not com- petent enough to perform on an air- plane. Welding is the biggest example that comes to mind. Sure, I’ve dabbled in it, and even met the requirements for my A&P Certificate. I remember tak- ing the practical test for the A&P and explaining all I knew about welding and emphatically stating to the examiner that I knew I was not competent enough to weld on aircraft and didn’t intend to do it anytime soon. Some of you may be aware of the recent This is a good example of personal limitations being pushed. Lots of bad wiring practices nosegear service bulletin issued by Van’s here, all of which were hidden behind the panel.

Vic is a Commercial Pilot and CFII with ASMEL/ASES ratings, an A&P, DAR, and EAA Technical Advisor and Flight Counselor. Passionately involved in aviation for over 36 years, he has built nine award-winning aircraft and has logged over 7500 hours in 69 different kinds of aircraft. Vic Vic Syracuse had a career in technology as a senior-level executive and volunteers as a Young Eagle pilot and Angel Flight pilot. He also has his own sport aviation business called Base Leg Aviation.

60 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes These were all pulled out of the same RV-10: Solid copper wiring with splices, screw wire splices, repaired circuit breaker, and three splices within 18 inches of wire.

I acknowledge that I still need lots of robust and proper wiring practices, so learned to fly, and they primarily focused practice, but these are the best welds I don’t hesitate to get help. Consider one on the airplane. With the recent advance have done in my life, thanks to the EAA SportAir TIG Workshop. of the EAA Sport Air Workshops on wir- in avionics, especially automation, I ing as a starting point. believe there has to be just as much I mentioned earlier, and I did manage to focus on preflighting the pilot. In many get some decent welds by the second Operating Limitations ways today’s newest Amateur-Built air- day, but it takes lots of practice and expe- When it comes to operating limitations, craft rival and even exceed the capabili- rience. I’m pretty sure taking this class we’ve probably all seen a few people ties of the newest airliners. Autopilots was not unlike learning to fly—it’s really disregard them, whether it was flying can be engaged as soon as you dare a license to learn. As soon as I find a good with multiple people in the cockpit dur- on takeoff and then completely fly the deal on a TIG welder I will start practicing. ing Phase I or flying outside the test area route, the approach, and even execute prior to completion of Phase I. Some- the hold if a missed approach is neces- Electrical Systems times they got away with it, and some- sary. But that doesn’t mean the pilot’s Unlike welding, one of the areas I am times the outcomes were tragic. The skills, proficiency, and understanding pretty good at is the electrical system, FAA recently released Advisory Circular of the systems is on the same level. And and I’ve been performing a pretty fair (AC) 90-116 that now spells out when especially for newly-rated Instrument number of panel upgrades this year. it is appropriate to have an additional pilots operating in some of today’s com- I really enjoy that part. What I don’t pilot in the cockpit during flight-testing plex airspace, things can get ugly really enjoy is seeing some of the really poor of Amateur-Built aircraft. Unfortunately, fast. Much like welding, it takes practice wiring jobs on some aircraft. I’ve seen it is a little complicated in that there are to become proficient with the new sys- way too many recently where personal requirements for both the crew and the tems. Time spent in the cockpit on the limitations and skill levels were wildly airplane. I think the crew requirements ground is time very well spent and can exceeded. As an example, I assure you are very well spelled out and appropri- pay many dividends if things go wrong that there is no room for 14 AWG solid ate, but I think they will be hard to meet in flight, whether it’s a real systems fail- copper household wiring, screw-type in most instances due to currency-in- ure or expedited requests from ATC. wire splices, and repaired circuit break- type and total in-type experience. I bet It is important to know how to use the ers in any aircraft. Period. I had an RV-10 those who are pre-disposed to not fol- equipment, as well as ensure it is doing come through recently that was so bad low the rules will continue to not follow exactly what you want it to do, and if we agreed to rewire the entire aircraft. the rules. I hope I am proven wrong. not, how to stop it. I think the saying It’s really a shame, and almost criminal, to As a DAR I have begun adding the ver- that “the pilot is the final authority as sell an airplane in this shape to an unsus- biage to the limitations that allows an to the operation of the aircraft” is really pecting buyer. By the way, a pre-buy was additional pilot onboard when in com- pertinent here. done, and the buyer was told the wiring pliance with the Advisory Circular. All of this doesn’t mean we shouldn’t was fine! So sad. When you look at the delve into new areas, whether it’s build- picture, I hope you cringe as badly as I Pilot Skills ing, flying, or learning a new skill. Just did when I saw this. Yes, these came out The last area of personal limitations I take the time to ask whether you might of the airplane and were not “built” for want to highlight has to do with the be exceeding your personal limitations. this column. Bad practices aside, today’s actual flying. We all learned the proper No sense getting scared when we should interconnected avionics really require preflight procedures when we first be having fun! See you next month. J

Photos: Vic Syracuse KITPLANES May 2015 61 Stressing Structure

Algebra and the

This RV-3 elevator Elevator bellcrank illustrates a typical control system. The autopilot servo and pushrod were installed Control with mocked-up hard- ware that was replaced System before flight. By David Paule

We’re going to determine the loads what the loads are. The loads in a deter- elevator using a control stick, the limit in the major parts of an elevator con- minate structure can be defined by the load is 167 pounds. If we wanted a control trol system. The particular system here conditions of equilibrium. In an indeter- wheel, the elevator force would be 200 is similar to that of many aircraft, using minate structure, you’ll need to consider pounds. We’ve got a stick so our load is a pushrod back to the elevator. Another the relative stiffness of the various parts 167 pounds. On Experimental aircraft, popular approach would be to replace because they share the loads; we don’t it’s not necessary to follow the FARs, but the large pushrod with stranded wire know which part carries what load with- they embody lessons learned the hard way cables. We’ll discuss a cable aileron con- out factoring in their relative stiffness. and there’s little reason not to. trol system in another article. We don’t need to do that here. We’ll start with the load P at the This article will use a considerable While it’s not required for Experi- stick and take it back to the elevator. amount of basic algebra and trigonom- mental aircraft, a certified aircraft’s -con The first thing we should do is make a etry to find and track the loads through trol system has to be designed for the free-body diagram of the control stick the airplane. The math isn’t hard, and if control forces of FAR 23.397. For the (See Figure 2). you have a calculator, you can find the trigonometry numbers easily. Otherwise there are online resources. The Control System Figure 1 shows the control system we’re going to consider. This structure is “determinate.” In other words, a free- body diagram is sufficient to determine Figure 1. Typical elevator control system operated with pushrods.

62 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes With this, we can make a free-body Stressing Structure diagram of the bellcrank and find its pivot force. The reaction force is: Rbell = Fb + Fd This force is applied to the parts that support the bellcrank. Usually this would be some sort of fitting attached to a bulkhead. Don’t forget that the fitting puts this load on the bulkhead, Figure 3. Free-body diagram of the bellcrank. and that the bulkhead needs to be able to carry the load. is called a free-body diagram; we’ve Knowing the force on the large push- Figure 2. Free-body diagram of the control removed all the external connections rod, we can find the bending moment on stick. to the stick and replaced them with the the elevator horn. forces they exert, setting the control Me = Fd * e There is a certain similarity in this stick unconnected and free. Since the analysis to a weight and balance calcula- stick is not accelerating, its forces and This moment is what the elevator tion. In both cases the job is to find the moments must balance, as Newton told itself needs to be able to bear. If the aero- moments and then either find a distance us, and that requires a reaction force: dynamic loads aren’t that large, and they or find a force. The basic relationship is R = P + Fb often aren’t, especially when the aircraft the same: is on the ground, the elevator control Moment = force * distance stops need to support that load. The Bellcrank That’s about all it takes to find the To get either the force or the distance, Now that we know the force that the loads—except that it’s also worth checking if you have the moment, divide the lower pushrod pushes against the bell- the forces at the full deflection each way. moment by the other. crank, look at the bellcrank at the other The analysis is the same sort of thing, but A moment, as used here, refers to a end of the lower pushrod. The moment now there are angles to consider. When bending moment. If the elevator control on the bellcrank is: the elevator in the sidebar example is system used a torque tube, that would Mb = Fb * c 30° up, the control stick is 16° aft. The be in torsion, and it would still be a free-body diagram for the control stick is moment. Regardless of whether it’s tor- And, like before, the force on the large shown in Figure 4. sion or bending, every moment is still a pushrod is therefore Since the small pushrod is long com- force acting perpendicularly to some dis- Fd = Mb / d pared to the movement of the lower por- tance or length. tion of the control stick, it remains close From that, and by looking at Figure enough to horizontal that we’ll call it 2, we see that the bending moment horizontal. But the pilot’s force applied at the control stick pivot is the force to the control stick is at the 16° angle, times the distance: as is the bottom section of control stick, M = P * a length b in Figure 1. We’ll have to resort to some trigonometry. In this case, since This is the moment that the control the small pushrod is horizontal, it only stick will have to withstand at the pivot. carries horizontal force.

The force at the lower end, applied A Bit of Trigonometry to the small pushrod, is the moment Here’s the first trigonometry lesson for divided by the distance from the pivot to the day: the small pushrod: Fb = M / b The control stick pivot carries a reac- tion force R that reacts these two forces, the hand-applied force, and the lower Figure 4. Control stick shown in full up Figure 5. Basic trigonometry relationship, pushrod force. This is why Figure 2 elevator position. showing the sine and cosine of angle N.

Illustrations: David Paule, Photo: Paul Dye KITPLANES May 2015 63 Any length or force like A that’s at an angle to the reference coordinate system can be transformed into its components, which have to be perpendicular to each other. You’ll have to look up the values for the sine and cosine of angle N or get it online or from a scientific calculator. The moment at the pivot is still M = P * a since P is perpendicular to a. The force applied to the small pushrod is Fb = M / (b * cos 16°) Figure 6. This sketch shows how even with skewed parts, a control system can have pushrods perpendicular to bellcranks or control horns. The horizontal and vertical components of the reaction forces on the pivot are Time for another trigonometry lesson: The moment at the bellcrank becomes Rh = (P * cos 16°) + Fb Sometimes, like now, we want to M = fb * c* cos G which means that the force and know the angle and all we have are the Rv = P * sin 16° components or one component and the on the large pushrod is main leg, like now. In this case, f is the Fd = M / (d * cos G). The next step is to look at the bellcrank component and c is the leg. The bell- and see what it’s doing. No surprise, the crank rotates to an angle we’ll call G: We already know that the elevator small pushrod pulls the bottom forward. -1 has a travel of 30°, which means that the How much? Looking back to Figure 1 G = sin (f / c) moment applied to the elevator, or more and the trig lesson, we see that the small and the expression “sin-1” means the likely the elevator stops, is pushrod has moved angle whose sine is f / c. It’s also called Me = Fd * e * cos 30° f = b * sin 16° the “arc sine” or “arcsin.” Again, you can where distance f is the amount that the look it up, get it online, or from a scien- I’ve drawn this idealized control sys- small pushrod moves. tific calculator. tem so that the parts are mostly hori- zontal and vertical. But some elevator control systems have some part at an Loads In Elevator Control System angle. Unless you have a definite rea- Here’s what we know about it: son for doing it (one reason might be P = 167 lbf Limit load at the control stick, pounds of force to get differential ailerons, were you a = 12 in Length from the pivot to the hand grip on the stick designing an aileron control system), b = 4 in From the pivot to the small pushrod you can avoid some surprises by making c = 3.5 in On the bellcrank, the bottom length the parts perpendicular to each other d = 4.0 in Top length of the bellcrank in the neutral position. Figure 6 shows e = 2.5 in Elevator control horn length an elevator control system with perpen- Moment at the control stick pivot: These moments and forces are all limit loads. dicular relationships. J Mpivot = P * a Mpivot = 2004 in lbf Davi David Paule retired after Force on the small pushrod: 30 years of structural Mpivot analysis and is now build- Fb = Fb = 501.0 lbf ing an RV-3B to keep b from getting bored. The

The reaction force on the pivot is: d structural engineering R = P + Fb R = 668.0 lbf included a mix of aircraft

The moment on the bellcrank: Paule and spacecraft. He has Mbellcrank = Fb * c Mbellcrank = 1754 in lbf been a private pilot since age 18 and currently owns Force on the large pushrod: and flies a Cessna 180. Mbellcrank Fpush = Fpush = 438.4 lbf d Moment on the elevator: Melevator = Fpush * e Melevator = 1096 in lbf —D.P.

64 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes Camera Mounts SHOP By Jim Fleischman TIPS

Action cams are pretty popular, and I picked up a small HD one (a favorite of RC helicopter groups) for some flight videos. I fabricated several mounts for my RV-4 that should work for a variety of aircraft. They are made from 3/4-inch wide x 1/8-inch thick strap aluminum and 13/4-inch suction cups that I found online. Besides the suction cups, the straps have a slight clamping action to help keep the mount tightly attached to the plane. A couple of rivets hold the straps together, and foam and felt strips were added to prevent scratching. The mounts work great, and you can’t beat the price—about $7 each. J The view from the action cam mounted on the tail of the author’s RV-4.

This mount attaches to the vertical stabilizer and is held in place Two rivets fasten the wing mount’s aluminum strips together. Felt with suction cups. strips prevent scratching.

The camera attaches to the mounting bolt near the top of the The wing mount is typically positioned near the left wingtip. The vertical stabilizer mount. camera attaches to the bolt on the inboard side of the mount.

KITPLANES May 2015 65 Getting Advice from the Internet By David Boeshaar

I love the Internet. Without the experts say…” or “My cousin Bob 3. Consider answers from someone Internet, I believe it would have been says...” Second-hand advice is like with a completed project that is fly- almost impossible for me to build my second-hand smoke. ing to have more weight. homebuilt project. I may be a new guy to 4. When you see two sides to an issue homebuilt airplanes, but I programmed discussed, ask: “Would Cessna do on punched cards and knew the Inter- that?” If Cessna would do it, I would net when it was called ARPANET and probably add weight to that side of BITNET, so I know if an answer to a the discussion. But remember, just question is known on the planet, you because Cessna would not do some- will probably find it on the Internet. thing doesn’t make it a bad idea. The problem with the Internet is that Cessna does not build Experimental for every right answer you find, you will aircraft for sale. often find many wrong answers. In the 5. When conflicting opinions occur, case of Experimental aircraft, there are the factory kit manufacturer is many listserves, discussion groups, web always right. sites, blogs, and FAQ sites that are just 6. Be very cautious about issues that waiting to help you. There is no short- involve safety of flight. The Inter- age of free advice. Some of that advice net is full of dangerous advice. Pay is vital, some is thought provoking, and attention to the kit manufacturer, some of it is dangerous. EAA tech counselors, or AP/IA pro- So, how do you separate the wheat Bob said, “Fill it with Bondo and it will fessionals. Using an LED flashlight from the chaff? Well, there is no real be OK.” or two for landing lights is different easy way to discover good from bad, but than not putting in factory-designed there are a few tips you can use to move 2. Don’t keep searching for an answer parts to save weight. through the morass. Here are some tips you already want to hear. If you look 7. Pay attention when different opinions for finding better homebuilding advice long enough, you will probably find arise from superstitious behavior or on the Internet: it, even if it is the wrong answer. old wives’ tales (OWT). Remember, 1. Be cautious of any advice that starts Read and understand both sides of bloodletting was used to cure disease with “He says…”, “They say…”, “The the issue. for over 2,000 years.

66 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes 8. Listen to people who have the most skin in the game such as people with flying projects, folks who make parts for sale, the factory that sells the kit, or EAA tech counselors who have their professional reputation on the line. 9. When asking for advice on a prob- lem, be sure to carefully and fully describe the problem. Include pic- tures whenever possible.

...and leave your engine monitoring to EIS. Trusted with everything from 2-strokes to turbines for over two decades.

“Does that look OK to you?” FLY IT 10. Finally, remember that the Inter- like you stole it... net may not always have the best answer. A visit to a project or a person visiting your project may www.grtavionics.com • (616) 245-7700 be the best solution. Of course, an Proud sponsor of Tiger Airshows and airplane “thief” extraordinaire, Hotwire Harry! email with pictures to the factory is always a good idea. J Davi David Boeshaar is a systems analyst for corporate Print and Digital Disney. A former mechanic, teacher, and computer d help desk guru at a major

Boeshaar university, he is now build- ing a Van’s RV-9A for fun with his brother-in-law. As the new guy in aviation, Dave has learned lots, both good and expensive, and hopes to pass along a little help to the builders coming up behind him. Either Format – Great Savings! Subscribe Now at www.kitplanes.com/subscribe

Photos: David Boeshaar KITPLANES May 2015 67 Data plate questions, airworthiness certificate errors, complying with service bulletins. By Mel AsbeRry

Question: I have assembled a the month and year. However, you may It states that annual inspections Lycoming O-235 engine, which put whatever you want. must be performed to look for does not have a data plate. The Question: A friend recently pur- cracks. If no crack is found, the SB crankcase is identified with a serial chased an already flying Van’s RV-8. is complied with and the horizon- number, which does match the In the following months as he was tal stabilizer should be inspected engine logbook. How do I identify reviewing the aircraft documen- annually as part of the condition this engine and must this data be tation in more detail, he noticed inspection. If a crack is found, there affixed to the engine? a typo on the airworthiness cer- is an invasive procedure for repairs. Answer: If the data plate has been tificate: The N-number’s last digit My question is this: In order to get removed from your engine, it is likely was incorrect and the airworthi- my airworthiness certificate, must I because someone has modified the engine ness certificate does not match the complete the invasive repair, or can so that it no longer meets Lycoming’s registration certificate and FAA I plan to inspect annually? In com- type design. If the engine is installed in records. Who should he contact to ments I’ve read online, about 80% an Experimental aircraft, it does not have correct the airworthiness certifi- of the RVs affected by this SB are to have a data plate. As a matter of fact, cate? Will the aircraft be grounded not showing signs of cracks and are if the engine has indeed been modified, until the revised airworthiness cer- being inspected annually. then Lycoming does not want their data tificate is received? Answer: There is no need to install plate on it. Answer: This is not all that uncom- the repair on a newly built aircraft. You Question: Is the date of manufac- mon. And there’s no need to ground may comply with the service bulletin ture required on the data plate of the aircraft. Any FSDO or a DAR with by way of inspection annually. Just as an Experimental aircraft? function codes 46 and 33 can issue a an FYI, on every aircraft where I have Answer: No, the only information replacement airworthiness certificate. found cracks, it was also found that the required on the data plate is make Of course, the FSDO will do it free of spar had not been properly deburred. I (builder), model (as shown on the reg- charge, whereas a DAR will probably have inspected many aircraft that have istration), and serial number (again as charge a small fee. Be sure to check the been flying for years without cracks. shown on the registration). The date of operating limitations for correct infor- My personal RV-6 has been flying since manufacture is not required. If you want mation while you’re at it. early 1993 and has no cracks. J to put this information on the data plate, I am working on an older RV-6A you may. The official date of manufac- kit and see that Van’s Aircraft has Please send your questions for DAR ture is the date the airworthiness cer- put out Service Bulletin 14-01-31 Asberry to [email protected] with tificate is issued. Many people just put for the horizontal stabilizer spar. “Ask the DAR” in the subject line.

68 KITPLANES May 2015 Photo: Mel Asberry BACK ISSUES List of Advertisers O NEW eBOOK O Please tell them you saw their ad in KITPLANES® Magazine. eBook download is the exact same KITPLANES® interactive makes it quick and easy for you to receive instant magazine as on the newsstand. information about products or services directly from our advertisers’ web sites. The difference is: ➥ Go to: www.kitplanes.com/links for a virtual shopping tour via links to their web sites. you get it now! ➥ Call the phone numbers listed below and be sure to tell them you saw their ad & in KITPLANES® Magazine. no shipping costs for e-books! Advertiser page # telephone Advertiser page # telephone Aircraft Spruce & Specialty CV4 877-4SPRUCE Builders’ Marketplace (a big savings for our international customers) Aerotrek Aircraft 73 812-384-4972 Aircraft Tool Supply Co. 51 800-248-0638 eBooks download as a single, full size, Airflow Performance 72 864-576-4512 full color .pdf document which you can view Avemco Insurance Company 25 888-241-7890 Bearhawk Aircraft 73 877-528-4776 on your desktop, laptop or tablet computer. Beringer 51 708-667-7890 Bede Corp. 71 See Advertisement PDF eMagazine issues are fully searchable Belite Aircraft 73 316-253-6746 and are compatible with all Adobe Acrobat Better Aircraft Fabric 43 907-229-6792 functions such as highlighting, page notes Better Half VW 72 281-383-0113 California Power Systems 49 800-AIRWOLF and spoken word audio. Carlson Aircraft 73 330-426-3934 Cozy 41 877-4SPRUCE O Individual monthly issues are $6.95 Falconar Avia Inc 70 780-465-2024 Flight Data Systems 70 831-325-3131 O A compiled Aircraft Buyer’s Guide CubCrafters 3 509-248-9491 is $12.95 Flight Grip 73 800-204-7625 Dynon Avionics CV2 425-402-0433 O All 12 issues from 2006-2011 on Glen-L 71 888-700-5007 a CD-ROM for $29.95 each year Experimental Aircraft Assoc. 43 See Advertisement Grove Aircraft 71 619-562-1268 + shipping. Homebuilt Help 72 See Advertisement Garmin International 13 913-397-8200 INFINITY Aerospace 70 See Advertisement Visit: Grand Rapids Technologies 45 616-245-7700 Innovator Technologies 70 403-669-3101 www.kitplanesbooks.com Grand Rapids Technologies 67 616-245-7700 Kuntzleman Electronics Inc. 71 610-326-9068 to order Ivoprop 55 800-FOR PROP Mountain High Equipment 71 800-468-8185 ❏ April 2015 Arion Lightning XS, STOL Mods, Fred to Florida, Bootstrap Testing, PS Engineering PDA360EX Mustang Aeronautics 70 248-649-6818 ❏ March 2015 Wag-A-Bond, Meredith Effect, Buying a Used Kitfox Aircraft 25 208-337-5111 Experimental, Communications, The New Guy Osprey Aircraft 72 See Advertisement ❏ February 2015 2015 Engine Buyer’s Guide, Backcountry Fox, Kitplanes® Bookstore 45 800-780-4115 Sonex T-Flight Program, Deciding What to Build Recreational Power Engineering 71 800-583-3306 ❏ January 2015 Mojave Gang Mo’Venture, Single-Seat Hot-Air Sensenich Wood Propeller Co. 73 813-752-3711 Balloon, One Week Wonder, Vetterman Exhaust Progressive Aerodyne 67 855-732-7395 ❏ December 2014 2015 Homebuilt Aircraft Directory, Inside Rotax, Smoking Airplanes 71 661-713-9050 Buying a Used Homebuilt, Souls on Board: 2 Sonex Aircraft, LLC 49 920-231-8297 Sportsman’s Market 70 800-SPORTYS ❏ November 2014 Glasair Diesel Sportsman 2+2, Fuel Injection, Mojave Experimental Fly-In, Sheet Metal Repair Stewart Systems 51 888-356-3490 Stewart Aircraft 71 See Advertisement ❏ October 2014 Starduster Retrospective, Touchscreen Shootout, Vinyl Wraps, The Plane-Builder’s Wife UL Power CV3 See Advertisement TCW Technologies 72 See Advertisement

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KITPLANES May 2015 73 builders’ marketplace

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74 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes Home Shop Machinist To launch a Light Sport–redux. Beginning with the September 2008 updates), and Jabiru’s west-coast dealer That question was answered late one issue and ending June 2010, KITPLANES® at the time, Jim McCormick, he got it all evening in January 2014. I was curiously published a succession of articles chroni- sorted. By the time the story culminated browsing Light Sport aircraft for sale cling the late Bob Fritz’s experience with the recounting of its first flight, on Barnstormers (www.barnstormers. constructing a Jabiru J250-SP. Although Jabiru two-six-niner-niner-tango had com) and there it was: “Jabiru for sale, it opened like the typical builder’s jour- become one of the most, if not the most, built by Bob Fritz. Make offer.” I imme- nal—how and why I picked this kit, thoroughly documented projects in the diately thought how cool would it be to etc.—it soon became apparent that “To history of KITPLANES®. do a “What Ever Happened To” article on Launch a Light Sport” would be anything I never met Bob Fritz. I did exchange a Bob’s plane. but. Bob took a warts-and-all approach. few e-mails with him about CNC machines The next day I called Li Vellinga (Bob’s Among other things, he was highly criti- in the spring of 2009. He mentioned he widow) and explained how I now write cal of the documentation, which was had been recovering from what, at the the “Home Shop Machinist” column outdated, and took frequent swipes time, appeared to be successful surgery (that her Bob had started) and what I at the haphazard manner in which the for brain cancer. Alas, by 2010 the cancer wanted to do. We talked for some time hardware was (dis)organized. had returned, and he passed away in early about the history of the plane and why Nonetheless, Bob pushed on and with 2011. It was very, very sad. she was selling it. She said when Bob the help of several friends, including Rob In the ensuing years, I often won- died, she considered flying it instead of and Mark Kirkpatrick, the Jabiru folks dered what ever happened to Bob her Cessna, but it was just too much to in (who supplied a stream of Fritz’s Jabiru. deal with emotionally. She agreed that a

In addition to his regular Home Shop Machinist column, between September of 2008 and June of 2010, KITPLANES® published more than a dozen articles by Bob Fritz about his Jabiru project.

Bob Hadley is the R&D manager for a California-based consumer products company. He holds Bob Hadley a Sport Pilot certificate and owns the VW-powered Victory Stanley Fun-Kist.

Photos: Bob Hadley KITPLANES May 2015 75 The series touched on virtually every aspect of the design and construction of the Jabiru J250SP. follow-up article would be a nice tribute the air was the priority. It’s understand- Over the next few days and weeks, to Bob, and she’d keep me posted on able that to him, these were non-essen- it became more and more urgent that the sale. tial details that could wait. Li sell the Jabiru. She had hoped that it The Jab had only been flown occa- A few weeks went by and there was would sell quickly because she had made sionally since Bob died, so it was basi- no word from Li, so I called to see what plans for the space in her hangar (she cally like new. At the time of the listing, was up. She mentioned getting one lives west of Sacramento, California, on the engine and airframe had just over offer, but they retracted it after finding an airpark property). With no sale pend- 60 hours total time. But, as any builder out it was built from a kit and not fac- ing, she was forced to temporarily move knows, “finished” for the purpose of the tory-built. Maybe they just didn’t know the Jabiru to her neighbor’s hangar to airworthiness inspection and “finished” the plane’s history. It’s wrong to assume make room. to take to Oshkosh are two different factory-built is outright better than ama- Just in time, a buyer stepped forward things. The outside was plain white, the teur-built. For the most part, so-called with an offer to purchase the Jabiru. wheelpants had never been installed, amateur-built airplanes are anything Even better, it was someone familiar and the interior was bare. Even the but. Building your own airplane comes with the plane from the articles and seat cushions needed upholstering. It’s with the understanding that your life was, you could say, a fan of Bob Fritz! impossible to fault Bob for neglecting and the lives of your passengers depend The deal required a condition inspec- those details. I am sure that getting it in on doing things right. tion by an A&P, as well as a review and

Bob Fritz occasionally mentioned his health situation in the final installments of “To Launch a Lightsport.” The articles were published two years removed from the actual construction.

76 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes On the day of the sale, Li Vellinga with Bob Three Bobs: Bob Davidson (owner of the house and hangar in the picture), Bob Hadley, Fritz and his puppy Ready-Redi. and Bob Fritz (in spirit) living on in Ready-Redi, the Vizsla puppy. (Photo Li Vellinga) sign-off on all the factory service bul- Madera or Bakersfield and take him interested when she suggested—not letins. The buyer also needed, as a con- back to her place. so subtly, but still very sweetly—that I dition of insurance, four hours of dual As of this writing, Bob Fritz’s Jabiru should make her an offer. She kept insist- instruction and six landings with a cer- has been in the hands of its new owner ing that I would be the perfect person to tified flight instructor. for 10 months. In that time the seats buy Bob’s Jabiru. And I kept agreeing— Li pulled it all together in one were upholstered, the interior finished, sort of passing the Home Shop Machinist swoop! She and the buyer mutually and the wheelpants installed. The exte- torch, if you will. agreed that A&P mechanic, CFI, and rior was spruced up with some wacky So there you have it. Now you know Jabiru builder Milt Cialariello would be zebra stripes (in keeping with a theme). what happened to Bob Fritz’s Jabiru! J perfect for the job. Milt would spend The plane is flown regularly, usu- the week going over the plane. The ally local, but it has been over the San Find out more online! Bob Fritz’s HSM buyer would arrive Friday evening to Gabriel Mountains a couple of times— columns and his series “To Launch a Light be briefed on the airplane and its sys- once to Kernville for a mountain-biking Sport” are available to subscribers on the tems. On Saturday the dual instruction trip and to Bakersfield to attend a Jabiru KITPLANES® web site (www.kitplanes. would consist of hopscotching local engine class. com). Log in (or create an account if you’re airports more or less en route to the In case you haven’t guessed it already, not already using the subscriber features buyer’s home field in Southern Cali- the buyer is me! No, I was not in the mar- of the web site) and then click on the fornia. Li would follow in her Cessna ket for an airplane when I first contacted E-library and you can browse back issues and pick up Milt somewhere around Li about this story. I guess I became or search for all of Bob Fritz’s writings.

Upholstery and carpet helped put the finishing touches to the Bob Fritz’s Jabiru as it looks today with the final paint scheme and interior. The unusually large cargo area (for a Light Sport) can fit a the wheelpants installed. bike or a gaggle of gear for cross-country trips.

KITPLANES May 2015 77 Spring systems. On airplanes with manual flight con- airspeed is decreased, the opposite hap- There are two disadvantages to bun- trol systems, designers try to design the pens, and the elevator moves trailing- gee trim systems. The first is that they control surfaces and linkages so that edge down. The sense of the elevator can be annoying to the pilot. If the spring the combination of aerodynamic hinge motion opposes the change in airspeed. is strong enough to trim the highest stick moments generated by the surfaces and The airplane will have a greater tendency forces the airplane will generate, then the mechanical advantage of the linkages to hold its trimmed airspeed, and the the spring forces will be of the same provide the pilot with the right force feed- stick force required to hold it at an off- order as the aerodynamic forces acting back in the stick for good flying qualities. trim airspeed will be increased. on the controls. The pilot’s “feel” will Sometimes, this is not possible, or the A down spring does not actually change therefore be composed of roughly equal airplane exhibits some undesirable char- the stick-free static margin of the airplane parts of spring force and aerodynamic acteristics once it is flying. In these cases, since it does not change the variation of force. The pilot will thus be “flying the one approach to giving the pilot proper pitching moment with angle of attack. It spring” as much as he is flying the air- pitch feel is to use mechanical springs to does produce an apparent change in stick- plane. If the spring system is not properly compensate for, or augment, the aerody- free pitch stability because of its effect designed, the spring can interfere with namic forces feeding into the stick. Sev- on the change of pitching moment with the pilot’s control feel, making the stick eral types of systems are used, each for a airspeed. Down springs are very common forces excessively heavy, and make the different purpose. and will often prove to be an effective fix. airplane unpleasant to fly, particularly In some situations, however, an airplane during maneuvering. On the other hand, Down Springs with a down spring will have stick-force spring feel systems, if properly designed, A down spring is just what the name gradients that meet acceptable standards can also be used to tailor and improve implies. It is a spring in the control sys- and will still have a dynamic pitch control- the control feel of an airplane. tem arranged to pull the stick forward lability problem due in part to a problem Another disadvantage of spring trim and the elevators down. Usually a down which is being masked or exacerbated by systems is that their effectiveness var- spring is set up to provide a nearly con- the down spring. ies with airspeed. The spring exerts a stant force over the normal range of ele- constant force on the stick. The force vator deflection. Down springs are used Spring and Bungee exerted by the elevators varies with air- to help fix problems with speed stability Trim Systems speed. Thus, with a fixed spring setting, and stick-free instability. One very simple way of relieving stick the position of the elevators will change Down springs operate by working the forces is to attach a spring or a bungee as airspeed varies. If the spring is pushing aerodynamic hinge moment of the eleva- to the stick, which provides a force that on the stick (producing a trailing-edge- tors, which varies with airspeed against opposes the stick force. This type of trim down moment on the elevators) it will the constant force of the spring. The system is used on a number of airplanes, act like a down spring, and its effect will spring holds the elevators more trailing- including the Schweitzer 1-26 and 2-33 be stabilizing. If the spring is pulling on edge down than they would float if the gliders. The spring or bungee system has the stick, it will act like a “reverse down spring were not present. The trim tab is set the primary advantage of mechanical spring,” and its effect will be destabiliz- to push the elevator trailing-edge up to simplicity. No linkages must be routed ing. This can be particularly troublesome oppose the spring. If airspeed increases, to the tail of the airplane. Usually, some if the spring is pulling on the stick to trim the aerodynamic forces on the elevator method of varying spring tension is pro- the airplane on final approach. The final opposing the spring increase, causing vided, so the pilot can trim the airplane approach and landing flare is one of the the elevator to move trailing-edge up. If as airspeed varies. more precise pitch-tracking tasks a pilot

is a principal aerodynamics engineer for Northrop Grumman’s Advanced Design organization. A private pilot with single engine and glider ratings, Barnaby has been involved in the design of Barnaby Wainfan unconventional airplanes including canards, joined wings, flying wings, and some too strange to fall into any known category.

78 KITPLANES May 2015 www.kitplanes.com & www.facebook.com/kitplanes has to fly in normal operations, and a destabilizing influence that gets worse as the airspeed drops is highly undesirable.

Spring Cartridge Systems The primary disadvantage of a spring trim system is that the pilot is feeling a mixture of aerodynamic and spring forces through the stick, and they can sometimes combine badly. Another approach that has been used successfully is to try to take the aerodynamic forces out of the equa- tion, and provide the pilot with feel exclusively with springs. Often this Similar to down springs, the RV-8 uses springs to bias the forces on the aileron system, approach is used to enable the use of thereby trimming the airplane in roll by pulling slightly on the stick. tail surfaces that would give poor lon- Another way to do this is to deliber- has been very successful. Test pilot Chuck gitudinal flying qualities if the system ately design the elevators to produce Berthe test-flew the Venture and the depended on aerodynamic moments very low aerodynamic hinge moments results were reported in the September for pitch force feedback. and use a spring cartridge system to pro- 1993 KITPLANES®. Quoting Chuck, “Its fly- If the elevators have too little aerody- vide the necessary stick force to give the ing qualities are much better than most namic restoring tendency, the stick force pilot proper feel in pitch. certified airplanes I have flown.” required to deflect them will be small. A spring cartridge system is one in The Cirrus SR-20 and SR-22 use a similar This can cause the stick force per G and/ which springs are arranged to provide a system. On the Cirrus, an electric motor is or stick-force velocity gradient to be too centering force when the stick is moved provided to move the spring cartridge to low, making the airplane difficult to fly either forward or back. Spring cartridges trim the airplane. Moving the cartridge precisely in pitch. can be used to increase the stick force changes the neutral position of the cen- The hinge moment generated by a required to deflect the elevators and, tering springs. Since the elevator hinge control surface is proportional to both hence, the stick force per G and stick- moments are very low, the system will the area of the surface and its chord. For force velocity gradient. The springs can tend to hold the elevator at this neutral a given elevator area and control gearing, also be used to provide most or all of the position if the pilot lets go of the stick. the smaller the chord, the lower the stick force feedback into the stick. If the elevators are designed properly, force required to hold a given deflection. One advantage of a spring cartridge a spring cartridge system will not affect If the elevator chord gets too small, pitch system is that the pitch feel of the air- speed stability the way a down spring control will become oversensitive. plane can be tailored by adjusting the or simple spring trim system does. The This phenomenon faces the designer spring rate of the cartridge. The level of speed stability effects of these systems with a dilemma. High aspect ratio tail sur- sensitivity can be adjusted to meet flying arise from the interaction between the faces are more efficient. They give more qualities and can even be customized to aerodynamic hinge moment gener- stabilization for a given wetted area. individual pilot preferences. ated by the elevator and the mechanical Unfortunately, small-chord elevators will An example of such a system can be moment generated by the spring. If the tend to produce sensitive pitch control. found on the Questair Venture. The Ven- elevators have very low hinge moments, Another elevator-planform problem ture has unusually high aspect ratio tail the aerodynamic component is removed may be excessive aerodynamic balance. surfaces. As we noted earlier, this causes from the equation, and the spring car- It is not uncommon to put shielded horn the hinge moments of the elevator to tridge will act as a pure positioning spring. balances on elevators. They are a good be small and can lead to pitch-sensitive A secondary advantage of the spring place to put mass balances and they handling. Rather than compromise the cartridge approach is that the elevators reduce the floating tendency of the ele- aerodynamic efficiency of the airplane to will have no tendency to float with the vators, which is desirable. Horn balances provide proper hinge moments, Venture free stream in response to changes in also reduce restoring tendency. If they designer Jim Griswold took another tack. angle of attack. Because of this, there is are too large, this can be a problem. The aerodynamic balance of the elevator no difference between the stick-fixed One way to attack this problem is to was tuned so that the elevator had virtu- and stick-free longitudinal stability of change the aerodynamic configuration ally no floating tendency and very little the airplane, and the most aft allowable of the elevators to increase the amount restoring tendency. Springs in the control CG will be slightly farther aft than an air- of opposing hinge moment caused by linkage provide all of the pitch control plane with the same size tail and a con- elevator deflection. force feedback to the pilot. This approach ventional trim system. J

Photo: Scott Card KITPLANES May 2015 79 By Robrucha

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