FBB Section Five
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-FLY YARY -RUDDER TRIM- CURE?<CL ?ndIJrP0GsS letrer in the December R~ileiinindicates ths t some people are going to Cake action on the suggestion of offsetting the vertical fin to counteract the tendency of the plane (any plane with a right-hand turning engine) to t~rnleft in flight. After Pete saw this item, he iirote in to say that there are much easier ways of solving the problem than building in a major fixed component with delib- erate misalrgnment, Resides, what do you do if you find you have put in too much offset or not enough? The anseer is a siiriple fixed tab on the trailing edge of the rudder. Take a piece of .020 to .032 sheet a3uminum about 2 by inches, Drill three lj8" holes along one edge as shown, and use wood screws to fasten this tab to the LEFT 9LllE of the rudder bow at the farthest-aft point on the bow. This should be aidway between the second and third ribs. Have at least 3/4" of the metal dgalnst the bow. k~thyour fingers, bend the projecting portior! of the tab to the left about iD degrees and make a test flight. This much offset should be about right f3r crulsrng fiight. You can't get a fixed tab like this (or an ofrset fin rrther) to trim your ship for all ilight conditions, so cruising is the most aeslraole. Tabs of the same srze can also be used on one elevator to make T1rnor adjusrmen~sco overall :rim that aren? tworth the trouble of resetting rhe horizontal stabslizer, ,lany pilots like to trim out to zero stick (or rudder) forces for every flight condition, Pete doesn' t, which is why he hasn't bothered with trim on his own ship. Tne corrective forces are not big enough to bother and he likes to have the 'Yeel" of the ship. After seeing the item in the december Bulletin, he -nilde and tested a tab and sent in the accompanying drawing with word that this ss the easy "fix" for those xho feel that they have a problem. Page Nine 1/68 @ Our good friend JOF POP5 ov~rin Lynchburg,, Va., hjd an experience wsth f luttcr ancl did a 1 litlc bonrng up on it, anr passcd alcng a "nutshell" descripison of what rt'i all about and .i:kat to do ~~~1-el-1it occurs. 11-L luttcr 1.5 a wrbanicd? lcsondncc which ocrdrs ai a certain velocity uettrmined by the ~.,=ightdnd area of tht hsngtcl surfxce and rile amount of play in the controlling linklge." ihs best udy to keep iron havrng it in a proven design like Fly Baby is to stick 2s clo;e as possible to rhe pl~nsfor the control surfacrs to insure that they -;re no HEA\,iLER than the origindls. Also, be very carEful in buildrng the hrtlges and iontrol surfaces so that there is r,o play in the sgstem. For instance, if ~nebilcron 1s cllmped in pos~tion,it should be impossible to move the other =ileron, or get any Lateral vovemeilt of tlie stick. Anytiiing more than a trny SL~3f iTOVEITfnt of the col~trolsurface or stick under such conditions shauld ~OLDC tolkraied LJ f~l-iterskuuid QCCU~~n fllgr~t,rtduce power immediately and "bark out" of thc 11,ttcr r~inge,lrke rsght cxv.' Also keep a firm grrp on rshe stick, :;s this -?? 11 -IL 3r11-j help damp oui tht klvtter, but keep the stick from beating you L laci. c nl,? ~eLoreycilu can slort dorln out of flutter range. The principal 'ihing LO rcmember thougi-i il co -SLOW DOia, Ttiac rs the only way to stop it, i iaqve only encountered flutter in flight once and that %as in a J-3 Cub as 3: ,as recovering from a sprn 1 got flutter Ln the elevator and it scared n>e prestv good: I had to nang on to the stick pretty tight and continued to pull up js fast as I dared and was well down in the seat, The only way I could wash nf1 the exIra speed was to get the nose up, and the flutter dissapeared as the speed drspped. Tois occurred at ;ibout 85 mph. I had done about Six turns of sprn and hadn't been hbrryrng the recovery as I had plenty of air under me, 1: ceelns ir'nzt the bolt holes in the cl~vatorswnere they jorn were elongated 2nd Lke ca~lzshad stretched ioo so that there xgas a good l/2 to 3/4 of an inch >laT; I- tl~eeiezators at the tr~ILrngedge 1~1ththe sticic heid fir11.i. The krnge p-ns wcre a Li ttl~worn to<>. You can bet that I check for play in the co~trols <very prefl~ghtnow, --BEWS FROM '%OWN---- iTEDER" "he illtra Light Aircraft Associatron of Australia is trying to get kly Baby dpprqve~Tor home-building by our Australian counterparts. We can he I p them. >bat is, those who have built and flown rheir ships can help t1ie.i.. Within the rrext Sew days we ~1.11he mailing some forms to those we know have their ships Sinrshed aria ilyirig, You are requested to fill out the f~rmand get it back LC Pete as soon as possible, The form amounts to a brief resurnebf your experience with the ship and the opcratrng statistips of same, If you shauld get a zorm frorl both Pete and Hayden, just disregard one of them. Ke are trying to cover 43 1 bases and may dupiicate some pilots. At any rdte, the form should be sent to Pete clirecc so that he can in turn Set them back to the proper people 3s soon as possible. Those fello~~~sare as anxious to get started as we all \;ere at one time, They are not as fo~t~inateas we on regulations, and their designs have to pass full C,A,R, 21 ratings -or show evidence of a sufficient nuinber of thL design operating safrly for a good period of tjme in the country of origin. Page Teri 1/68 >lOW ON FLY BABY---- LtNDZNG CAPABILITIES GEORCE La..EPSII has pretty well settled tne doubts that anyone nay have had concerning the durability of the wooden landing gear an PLY BABY, Actually, it's 71ore the thought oi wood in this age of "iron birds" than any serious st~~dyof the problem that bothers the doubters. Check the cross-section of ihat gear: and yo~ylfino that FLY BABY has MORE than such famous old timers as the Ci~riiss"Jenny", and it sure took J beating! Fly Babys gear design, particularly the cross lamination feature, was directly inspired by the famous rrcnch SPAD fighter of W-I. Pete got a good chance to study one in his shop, having b3rrowed a non-flyable one from a friend and brodght it inio his shop to paint ii up for a museum display. A few other would-be builders have written in to ask if the narrowness of the gear wouldn't be expecteJ to complicate rhe grodnd-handling problems and lead to ground-loops, E LC, Far from it! Wide gears can be more trouble on the ground than narrow ones if a wheel is a little out of line or if a brake is dragging. Ihe farther o~ltthe wheel is from the centerline, the greater the ~~ultiplrcatio~of any such problem, took at gliders - they have the best 5r01~ndhandling charasterrstrcs of all, and they roll on ONE wheel! Fly Babys ;~aris relatively narrow, but Pete will stick by bis statement that it has ~e wos~doc~le g1-ound-handling cilaracterrs trcs of any homebuil t. Some examples : iigcirpiane pilot flying the original Fly Baby for the flrst time set it down .I a uaved runway and rmrnedlateiy noticed 2 tendency to turn Left that kept Lnsreasrng. Turned out the tire was flat. All rt took to keep it. rolling straighr was some r~glitrudder. Try that with one of the hot jobs! ITANCIS LONDO had a similar experience with his ship, and he wasn't nearly as experienced a pilot, In fact, he was flying on a student permit. He didn't have just a flat, st torned out - he had a broken wheel, Again the tendency EQ turn could be correcred with rudder. .,ow, before anyone tries to blame that one on the no-stlocks landing gear, it should be pointed out that Francis' wheels cam from an airplane that had been crashed, and that old cracks were found in che wheel after bis accident. ere aiso has olovres of a 50-hour pilot, who had never flown anything livlier tnnn 2 J-3 Cub, qakrng hrs frrs~landing in the original Fly Baby. You have J aec that bounce Lo believe it. Sonettirug over 800 hours on Pete's ssilip now, strll witn the original axles, and they aren't bent enough to be worth ihe effort 01 straightening. >10RF PRAISE. FOR \\.'LEDENS ' FITTINGS There mJst be a lot of builders aroucd that don" relish the idea of tne long hard hours spent over the fittings with hacksaw and file, This observation is based on the unusually large number of letters praising Dick Weedens' fittings. r!e have several of Dick's fitting:, ourself and .~vitl?autlapsing into a lot of 1avrsi-i "hollq-tiood" type adjectives, the only way tsje can describe them is "Perfect".