The ground crew poses for a photograph. This scene is similar to that in an original picture that the author found.

Zeppelin-Staaken XIV “R” Bomber Rarely modeled German giant electrified by Jim Beagle

This model has a presence in the air, with its 92.3-inch wingspan. Five brushed motors and gearboxes provide the classic bomber rumble.

26 MODEL AVIATION Photos by the author “R-PLANES” WERE THE German giants of the Great War. The “R” stood for Riesenflugzeug, which translates to “giant aeroplane.” These strategic bombers were a result of Ferdinand Graf von Zeppelin’s ambitions and imagination. He had realized how vulnerable his large dirigible airships would be as soon as airplanes could get to them. Zeppelin took advantage of the great space available in the airship sheds and built most of these bombers at the Berlin suburb of Staaken. Zeppelin-Staaken engines were housed in nacelles that were big enough for the mechanics to make in-flight repairs by literally working within each gondola. The massive 18-wheel undercarriage had to bear enormous weights, with huge 1,000- kilogram bombs. A ground staff of 42 was required just to get the aircraft out of the hangar. The Staaken was difficult to shoot down, with its size, defensive guns, and security of its five engines in tandem push-

Right: Five brushed Box construction is used for the front of the fuselage, with sides, GWS Speed 400s geared formers, and doublers keyed together. 3.0:1 provide the power. The nose motor is shown, installed within the cowl framework.

Below: Upper and lower horizontal stabilizers and elevators are identical. Pull-pull tubes are installed through the formers.

Jim designed the tail of the fuselage to incorporate a cross-stitch pattern of braided line. Braided line is passed through small laser- cut holes in the corners of each former.

Laser-cut “combs” aid in aligning ribs over the plans. Laminated interplane struts are attached to laminated ribs using Du-Bro straps. These provide a secure and easy method of attachment.

July 2010 27 1 Three /32 plywood ribs are laminated together to capture the Du- The top wing has two turrets built from 1/8 balsa and covered with 1 Bro straps. Spars are /8-inch-diameter carbon-fiber rods. 1/32 plywood.

Blue foam has been sanded to shape to form the engine nacelle. It is supported with light plywood and carbon-fiber rods.

28 MODEL AVIATION Each nacelle supports two motors: one as a tractor and one as a This shows the externally mounted radiators; each of the five pusher. The motors are mounted on a 10mm balsa stick. motors has one. The mechanic is standing in the access opening that made in-flight repairs possible on the full-scale aircraft.

The Staaken had an interesting defense method. Above each nacelle, a hole through the upper wing allowed crew members to This five-color lozenge pattern is a modified version of one that climb up a small ladder and fire their guns at the enemy Jim found on the Internet. He printed it on tissue and then applied approaching from above. it over Solite.

It takes a lot of wood to construct the Staaken; 47 sheets were required. Manzano Laser Works handled all of the laser cutting.

July 2010 29 Above: The Staaken stands ready for its first mission. The lozenge pattern helps it blend in with its surroundings on the ground or in the air.

Right: The five motors put out approximately 64 watts per pound. The amount of drag on this large bomber requires that it be at full power throughout the flight.

Watch the pull arrangements. Only two R-planes Datafile #123, Staaken at War, as a basis were lost during raids, and that was for the scale outline, with specific details because of a failed landing in fog and a drawn using AutoCAD 2000. The final Zeppelin-Staaken mechanical failure. drawing includes all necessary views for The Ukrainian government chartered building and a layout of all 47 laser-cut XIV Flight Video! one of the last of these biplanes that sheets. Zeppelin-Staaken built, R70/18, to Charlie Bice of Manzano Laser Works Keith Shaw piloted this design’s transfer funds into the country from provided expert advice, regarding wood second flight, which took place at the Germany. R70 was confiscated by the selection and laser kerf allowances, and Mid-Am Electric Flies event in Northville Romanians on September 19, 1919, other design assistance. This company Township, Michigan. Go to the Model following a forced landing at Bessarabia, was excellent, providing quick response Aviation Online Web site to see footage in Eastern Europe. and delivery times. Hardly any stock balsa showing how this behemoth handled the I had wanted to build a large bomber is used in this design; nearly everything is for sometime, and I was convinced that a laser-cut to fit. less-than-ideal weather conditions. MA —Jay Smith large World War I biplane was in my future when I saw the movie Flyboys. This CONSTRUCTION would be my first attempt at designing a Sources: Fuselage: After many hours of AutoCAD model. work, I was eager to get the CA flowing; I With the large quantity of ribs, this 1 8 Model Aviation Online started with the outboard rudders. The / project was perfect for laser cutting. I used (765) 287-1256 balsa parts were assembled over the plans, three-view drawings from Windsock www.modelaircraft.org/mag and I protected them with waxed paper.

30 MODEL AVIATION Thin CA was applied to the joints with a building board, and then the fuselage sides Staaken pilots had access to the top side microtip applicator. are assembled. You can also construct the of the fuselage in two places forward of the The upper and lower horizontal rudder servo tray inside the fuselage at this wings. The area between those openings was stabilizers and elevators are identical and time. The rudder and elevator are pull-pull, a natural place for a battery hatch. 1 contain /8 balsa parts. For extra strength in and the servo trays are designed for standard I attached the front cowl to the firewall key areas, I used laminated 1/32 plywood units in the proper orientation. with 4-40 blind nuts and socket-head 1 between two corresponding 1/16 balsa parts The front elevator servo is installed on its capscrews. Two /8 balsa fuselage doublers and then sanded to a common thickness side and supported by using parts V2 and are installed near the upper edge and two with the mating balsa details. both V3s. This method aligns the servo arm scrap pieces are glued to the fuselage floor, The front of the fuselage is a typical box with the elevator motion, providing a simple to give the landing gear straps something to construction. But it is more than 4 inches pull-pull line attachment. screw into. wide, so each side consists of two laser-cut 1/8 balsa parts adhered at the saw-tooth joint. Then the 1/8 light plywood fuselage doublers are aligned and glued to the upper and lower edge of the fuselage sides. I made the fuselage formers from 1/8 light plywood and balsa. Dovetail joints are used to assemble the four sides of each former, with the wood grain running in the direction that will maximize strength. The bottom sheet is pinned to the

Zeppelin-Staaken XIV “R” Bomber

Type: RC semiscale Skill level: Intermediate builder, intermediate pilot Scale: 1:18 Wingspan: 92.3 inches Wing area: 1,724 square inches Weight: 7.5 pounds Wing loading: 20 ounces/square foot Motors: Five Speed 400 with 3.0:1 gear Propellers: APC 9 x 4.7 Watts: 480 Power: 64 watts per pound Radio: Spektrum AR6200 receiver, Hitec HS-81 aileron servo, Hitec HS-425 rudder and elevator servos Other: Castle Creations Griffin-55 ESC (front motor and receiver), JOMAR analog ESC (four nacelle motors), 3S2P-4340 mAh Li-Poly battery

A smiling Jim Beagle with his completed aircraft and its crew.

July 2010 31 Full-Size Plans Available—see page 167

32 MODEL AVIATION Full-Size Plans Available—see page 167

July 2010 33 I wanted the Staaken to be powered by Wings: A unique attachment method is used through the rib holes in the upper wings, and five brushed motors and gearboxes, for that on the wing struts. Metal landing gear straps 12-gauge motor wires are installed in the classic bomber rumble. The GWS gearboxes (Du-Bro item 158) are laminated between two lower wings. Scrap balsa is added to the area are designed for 10mm square hard balsa 1/32 plywood ribs. A third plywood rib in the where the wires will come out of the wing sticks, which BP Hobbies sells in 12-inch middle is used to align and keep the strap in covering. lengths. place. I built the nacelle struts using four balsa The position of the gearbox was adjusted One end of the Du-Bro strap is drilled out lengths that create a hollow center, through to provide clearance between the cowl and the to 1/8 inch in diameter, for a carbon-fiber spar which the motor wires pass. The center of 1 /8 light plywood spinner backplate. The to pass through. Then the interplane struts can each interplane strut is 1/32 plywood and diameter of the 400 motor interferes slightly be attached to the straps with #2-56 blind nuts captures the end of the Du-Bro strap. The with the top stringer of the cowl frame, which and socket-head capscrews. center-section is sandwiched between two must be sanded to fit. Starting with one side of the upper wing, I pieces of 1/8 light plywood, glued, and 1 After I verified the clearances, I epoxied constructed the spars from /8-inch-diameter clamped together. the motorstick in place. The model’s cowl carbon-fiber rods cut to length. The rods slide 5 was created using four blue-foam blocks, into /32 brass tubing, per the plans. Two short Nacelles: These are similar in construction to adhered in place into the cowl frame with sections of wire are bent over the plans to join the cowl, with 1/8 light plywood forming the aliphatic glue. the two sections of brass. skeleton of the structure. I cut the 10mm x I employed a belt sander, then a coarse-grit The TE is pinned to the board over the 10mm balsa stick to length and installed it in sandpaper block, then a 220-grit sanding bar plans. The balsa ribs are “skewered” onto the the center nacelle section but did not glue it, to achieve the desired shape. The interior was rear spar, like a shish kebab. allowing the GWS 400 motor gearbox to be opened up with a drum sander on an electric Four laser-cut rib-alignment combs are temporarily mounted. rotary tool. utilized to help keep things straight during I glued four 4-40 blind nuts into the The Staaken XIV employed two assembly. I used thin CA to glue the ribs to firewall and then attached the cowling undercarriage legs with fairings to support the the TE and then adhered the ribs to the rear baseplate with 4-40 1/2-inch bolts. I dry- front axle. The front legs are two light spar with a drop of thick CA. assembled the cowl front plate with stringers. plywood struts laminated together. The front The laminated ribs are not glued until the Then I centered the spinner backplate onto the axle is also supported from the rear with a 3/32- upper wing has been removed from the board. prop shaft and clamped it into position. inch-diameter wire, bent to shape over the The front carbon-fiber rod spar is inserted plans. through the ribs, and the process is completed After checking that all parts are seated, I sanded a groove into the underside of the from root to tip. centered, and square, glue the assembly together. You can flesh out the nacelles by foam cowl in the area around the landing gear The 1/4 balsa dowel LE is glued to each adhering four sections of blue foam in place attachment rod. The strut attachment is a 5/32- rib. After all 1/16 balsa ribs are glued, I flipped inch-diameter brass rod inserted through the the wing over and aligned the Du-Bro straps and then sanding to shape. 1 I glued a paper copy of the cross-sectional cowl’s laminated stringers and epoxied in between each of the three /32 plywood ribs, place. clamped them together, and wicked CA into view of the nacelles onto a piece of fan-fold A 4-40 threaded rod then passes through the edges. Then I glued the “doughnuts” onto foam to use as a fixture spacer between the the brass bushing. The front landing gear each side of the laminated ribs, for lateral lower wing and the nacelle, to ensure the assembly was temporarily clamped in strength. proper incidence. The lower strut attachment position, to verify locations. I added two scrap Aileron ribs are keyed into the hinge line. points have a similar construction as the front pieces of light plywood and glued them The aileron tip is three pieces of 1/16 balsa, cowling, using the Du-Bro straps with 4-40 between the fairings, for a bit more strength. laminated and sanded into a classic wingtip threaded rod. The area around the landing gear is filled profile. The ribs are not thick enough to fully with spackle and sanded smooth. The 3/32 wire install the Hitec HS-81 servo and enclose it Final Fit and Assembly: The center rudder is axle, rear landing gear wire, and axle plate are with a hatch, but the servos are unobtrusive of conventional design with CA hinges, but lashed together using braided musky fishing with the wing undercamber. the outboard rudders are “balanced.” I line. The Du-Bro straps point up on the bottom inserted two short lengths of music wire into I fabricated the tail end of the fuselage wing, so the three plywood ribs can be each end of the rudder. These plug into short from four 1/8 basswood laser-cut stringers. assembled directly on the board. The ribs are lengths of brass tubing that are epoxied into The basswood stringers are glued to the rear assembled using the same methods as on the the upper and lower horizontal stabilizers, fuselage side and then glued to the front upper wing. thereby allowing the rudders to pivot. fuselage box. The formers are each assembled Although the lower wing does not have The center wing struts attach to four into notches in the basswood stringers. ailerons, it does have other design and points on top of the fuselage. Du-Bro metal The tail assembly is built over the plans. I building challenges. In addition to the swept- landing gear straps are bent at a 30° angle soaked the 1/16 balsa parts with water, bent back portion, it has 2° of dihedral. toward the center. them into a curve, and let them dry for a few The outer section of the wing is supported The carbon-fiber rod and straps are hours. on blocks at the appropriate angle, and the assembled in place. Lower wing spars plug The tail of the fuselage was designed to joiner wires are bent per the plans. Strut ribs into the brass tubes that span the fuselage. incorporate a cross-stitch pattern of braided in this section support the landing gear below Fuselage struts meet at the center of the top line. Starting on the bottom side of the box and the nacelle above, so there are five ribs wing and capture a Du-Bro strap on each end of the fuselage, I passed the braided line laminated together to set the correct angle for spar. through small laser-cut holes in the corners of the Du-Bro straps. The carbon-fiber rods and doughnuts are each former. The Staaken had an interesting method of aligned and glued into the fuselage. Nacelles I stretched each string segment taut and defense. Above each nacelle was a hole are again assembled to the lower wing. wicked thin CA into the hole to hold the string through the upper wing; the crew members Nacelle struts going to the top wing are in place. I applied a drop of thick CA after the could climb up a small ladder and fire their made from 3/32-inch-diameter wire slid into second string was passed through each hole, guns at the enemy approaching from above. I lengths of 4mm carbon-fiber tube. A short and then I sprayed kicker while holding the wouldn’t think that would have been the length of brass tube is pinched at the top of braided line tight. safest position with a Bristol Fighter coming the struts, and 2-56 bolts are attached through The crisscross pattern of braided line down on you! the Du-Bro strap. greatly improved the rigidity of the fuselage The turret box is framed with scrap balsa; while maintaining the lightweight structure. the box protrudes above the ribs by 1/8 inch all Finishing: I fiberglassed the nacelles with 3/4- Plastic tubes are threaded through the laser- around. The turret fairings and cap are built 1 ounce cloth and water-based polyurethane cut holes in each former for pull-pull lines to from custom-fit /32 plywood. mixed with baby powder to fill the weave. pass through. The 36-inch servo extensions are threaded

34 MODEL AVIATION Two more coats were needed to get a smooth elements. clicks of trim adjustment. The slight breeze surface. Ailerons are attached with a simple tape greatly affects the bomber’s light wing I added several panel lines using 1/16-inch hinge onto the Solite. Various pieces of loading, and rudder input was required pin-striping. Struts and nacelles were painted lozenge tissue are laid out to create the throughout the flight. with Model Master Intermediate Blue. The patterns for the ailerons. The hinge line is After a few minutes, the aircraft came in interplane struts were painted with Blue Angel simulated with a thin black line over a wider on the approach and settled in smoothly. An Blue. gray line, to give the illusion of depth to the hour later, under slightly less breezy Unable to find propeller spinners that were hinge. conditions, the second flight was longer and the appropriate shape, I happened upon some I created the Balkenkreuze (a stylized Keith was able to back off a bit on the plastic Easter eggs in the grocery store that version of the Iron Cross) with my throttle. would work. Each egg had a small package of publication software and then printed it chocolates inside, so I had to buy a few extra. simultaneously with the lozenge pattern onto I thank Keith, Jim Young, C.J. Wysocki, Yum! the tissue. Bob Foran, Frank Jaerschky, Charlie Bice, The backplate is 1/8 light plywood laser-cut Rick Cornell, Rick Allen, and many others to 2 inches in diameter. Four 1/4 x 3/8-inch Flying: The morning of the maiden flight who have supported me throughout this balsa blocks are glued and sanded to fit the brought only a slight breeze from the project. interior egg profile. Then I used a rotary tool northeast. The ailerons were programmed A special thank you to my wife, Deb, to cut the eggs to the correct size. with one-third less down differential. The and daughters, Rachael and Jordynn, for My propeller shafts are threaded, so I used three rudders had approximately 30° throw their support and tolerance of the many four small button-head screws to attach the and the two elevators had close to 20°. hours I spent in the basement building the spinner after mounting the propellers. The 16 wheels for the main landing gear Zeppelin-Staaken. MA are only 21/2 inches in diameter, so the Jim Beagle Covering: Some Zeppelin-Staaken bombers rollout on rough grass was difficult. I placed [email protected] had lozenge covering with large polygons of the Staaken on the smoothest part of the irregular patterns that were hand-painted on field and made final checks. Sources: the airframe. The R70/18 model used the I entrusted Keith Shaw with the sticks for conventional five-color, top-side lozenge this maiden flight. The sound of five Manzano Laser Works fabric that was preprinted and used on other propellers, five gearboxes, and five brushed (505) 286-2640 biplanes of the era. motors under full throttle was awesome. www.manzanolaser.com However, at a scale of 1:18, the lozenge Rollout continued for roughly 70 feet, fabric would be only 3 inches wide. To put when the model’s wheels finally parted with Du-Bro this into perspective, there are roughly 75 the ground. A full-power climbout was (800) 848-9411 polygons in a 3 x 3-inch area; that continued under a slow turn to the left. www.dubro.com extrapolates to more than 36,000 polygons on Suddenly the R70 pitched up a bit, and Hitec my design’s airframe! then all five motors cut out. An attempt to (858) 748-6948 The printed-tissue-over-Solite technique rearm the ESC was made, but the altitude www.hitecrcd.com was the only practical method to use to was insufficient to save it. The bomber came achieve this excessive amount of lozenge down at an angle and made an impact nose BP Hobbies pattern at this scale. Solite is made in first, with the front of the fuselage taking the (732) 287-3933 England and weighs only .6 ounce per majority of the contact. www.bphobbies.com square yard. I covered each part of the The nose gear and front of the fuselage airframe with this base layer of white sustained minor damage. Coincidently, GWS USA covering. according to the history books, front landing (909) 594-4979 I found the five-color lozenge file on the gear problems were also experienced in www.gwsus.com Internet in a PDF file and used publisher 1918. So I guess I followed “scale” a bit too software to customize the patterns. Standard closely. Spektrum tissue at my hobby shop is 20 x 30 inches, After making the necessary repairs, we (800) 338-4639 so I taped two sheets of copy paper to an 11 performed additional ground range checks www.spektrumrc.com x 30-inch overall size. and experienced some radio-frequency I sprayed a coat of Krylon Easy-Tack interference problems. The five brushed Mid-Am Electric Flies onto the carrier paper and then laid the motors created more of an electrical noise http://homepage.mac.com/kmyersefo tissue on the paper to smooth all of the issue than I had anticipated. Long servo wrinkles. I use an HP-9650 printer, which wires for the ailerons might also have been Castle Creations allows for direct-through printing of 11- part of the noise. (913) 390-6939 inch-wide paper. The printer settings are at I decided to purchase a Spektrum DX7 www.castlecreations.com normal. I find that the best ink setting transmitter and Spektrum AR6200 receiver. applies too much ink and causes more Installing the 2.4 GHz system resolved all Electronic Model Systems/JOMAR Products wrinkles. noise and servo interference. Keith and I (800) 845-8978 A thin coat of nitrate dope is applied to tested the motors at full throttle and cycled www.emsjomar.com the Solite-covered surfaces and allowed to the servos, with no glitches. dry. Then the printed tissue is positioned in A few weeks later at the Mid-Am place. There is still some Easy-Tack on the Electric Flies event in Northville Township, back side of the tissue, so it is simple to Michigan, I attempted a second flight. The reposition until you achieve the correct field was in great shape, and Keith was at location. the controls again. I brushed thinner onto the lozenge, which He applied full throttle and the Staaken soaked through the tissue and combined rumbled straight down the runway. Liftoff with the nitrate dope for permanent occurred with a slow climb and large adhesion. I also applied two more coatings circuits around the field. Full throttle was of 50/50 dope and thinner for a bit more required for most of the flight; there is shrinking. Last, I sprayed on a water-proofer considerable drag on this airframe. for additional protection against the Keith made a few passes and a couple

36 MODEL AVIATION