Free Flight Indoor Bud Tenny Figure 1 trailing-edge flap HandLaunched Glider wing can lots good things discussion column STEERING PROBLEMS past 18 months steering AMA models has become increasing problemone has three sources first source has fliers have increasingly expanded scope activity up including steering La Cal Scale models second part problem has Contest Directors let either fear being bad guy because really dont understand steering rules well enough third leg problem fliers stood muttered under breaths filing protests have four comments situation 1 CDs obligation SOB ifhe needs 2 steering rules difficult under stand addition Contest Board interpretation whole matter probably will reviewed next rules cycle Figure 2 PrImary traditional Indoor wing bracing Note useof compression ribs 3 Steering works well World Champion ships because rules written environment contestant meetings before official flying begins used sure everyone understands exactly what expected 4 Steering intentional part compe tition strategy international competition AMA Indoor fliers need decide desirable philosophy AMA competition before rules can fixed have seven pages single-spaced fine print comments circulated among Bud Tenny Rick Doig Del Ogren Bob B 4 Al 4 Figure 3 Air loads braced wing explanation column Clemens ModelNet earlier 1987 concerns steering problems causes both serious business entertalning reading can already log ModelNet takes computer modem cQnnec tion via CompuServe leave message sys op Doug Pratt 767033041 asking him access data want get ModelNet call Doug AMA HQ ask him just want read data send SASE $1 Ill send copy Figure4 Secondarybracingshownonlyon side helps air loads Peanuts & Pistachios No 2 Volume 2 interesting series has dozens really great P&P photos four three-views two full-sized plans some short articles Get $495 plus $150 P&H Bill Hannan PO Box Escondido CA 92025 HLG altitude control years ago Hal Blubaugh Denver area reported interesting results using fence flap tralling edge HLG wings small strip wood glued vertically along trailing edge forming vertical flap below wing own experiments discovered glide path less critical after warps removed washout used discussed July87 column adifferentlaunchtrajectory often needed small peaked ceilings open girders possible have glider pop out almost vertical position simply fly peak girder opening calibrate placement roll-out just below girders Since Blubaugh fence will also restrict maximum launch altitude recently used limit climb Glider somewhat too heavy ceiling ran strip about Y64-in deep out within 1 tip 14-in span tapered last inch strip zero See Figure 1 sketch Figure 5 Typical competition Indoor model compression Lower tension ribs After fence added could concentrate launch placement trim roll-out easier place Glider got step quickly less problem turbu lence important everything far consistent got several seconds higher total time did fence launch placement giving away two three feet altitude bottom line model weighs over six gramsin contrast 24 grams Stan Stoy used Category record-setting Coot best single flight027contrasts over 035 best site has interesting experiment Wing bracing schemes Wing bracing Indoor models used reduce wing structure weight Figure 6 Wing post extensions new bracing replace two compression ribs employing external rigging replace wing struc tore earliest bracing consisted tether wing posts leading edgekeeping wing bowing up next advance superstructure give support agalnst loads would deflect wing downward Figure 2 shows modern version primary bracing cabane bipod supports two bracing loopsone leading edge other trailing edge Besides providing support alr ground-handling loads rigging helps hold washin washout use Figure 3 shows air loading forces wing primary bracing arrows represent forces unbraced tips Figure 7 Completely removing cabane works also info column B arrows show resulting deflection spars between bracing supports So efforts reduce spar weight carefully done avoid excessive deflections under full torque steering ceiling-scrubbing loads Figure 4 shows next logical development secondary bracing allow major spar lengths lighter undue deflection under stress extra bracing wing tip left side sketch shows tip bracing sometimes used secondary bracing Are drawbacks two bracing schemes discussed above have major disadvantage due center support point cabane Uploads downloads wing put tension wires part tension force squeezes wing spars together answer use compression ribs Figure 5 stress points extra weight compression ribs especially extra-wide FAI wings partially offsets weight savings spars Figures 2 4 show compression ribs bracing points center rib builders use Actually center rib under tension balsa bottom piece can replaced wire Continued page 144 Figure 8 Rodemsky-style bracing superstrong locks wing/motor-stick together September 1987 61 BICO PERFORMANCE 0*00 t*uNCBEII CLIORAS FROM FULL SIZE PATTERNS TOUR CHOICEI ICLUSTRATRO EACH OR SIX PACK PICK OMI SOUTORASTERO PA B BOUGHTRUB4 BITECI phies citations great gab wave recognition chance witness some premier modelers land just important us experiences cannot matched easily forgotten Mothers little pilot returns home bruised battered happy indelible memories head Envious Dont Make big broad splash next years calendar mark USFFC 1988 lay travel plans Sell Mercedes mortgage ranch thats what takes Youll glad did FF Indoor/Tenny Continued page 61 What next Figure 6 shows next develop ment Primary bracing still supports wings tip dihedral extending wing posts above spar leading edge trailing edge tip bracing work off wing posts result much stiffer wing has light spars needs two compression ribs bracing scheme gives rise comment turn fly loose inside bracing gets away must have forgotten some wires Thats still too heavy scheme shown Figure 7 used stiff posts very careful tensioning wires gets rid cabane last two compression ribs wing has two weaknesses 1 sort loose floppy move wing post must youre mounting wing 2 Tip collisions building structure make wing twist isnt bad direction Remember TII ~GRAT LAK5 40 Wing 18 25 Engines Dealers ributors Welcomed Phone 703 273-9593 FLYLINE MODELS INC P o Boo 2136 Fo,foo VIrgInie 22031 U 5 twist washes out tip opposite contact point helps tip drop turning model away obstacle ultimate Well maybe notbut like scheme shown Figure 8 close copy dozens Erv Rodemsky has done integrated wing/motor-stick bracing ex traordinarily effective Y wing posts forming triangular structure little lighter really stiff wing posts ribs top Y tension ribs same wires form tension braces extend forward hook thrust bearing rearward hook rear hook Note fuselage wires dont have tight adequately brace fuselage motor hooked up stick bends slightiy wing motor stick locked rigid structure high angle wires separation between give lot strength torsional support motor stick motor stick start collapsetuck underin high humidity able grab prop shaft thrust bearing straighten out stick working against top bracing help unhooking motor saved whole model whereas might have lost added support top bracing Thats hope ye editor will able fit whole column dozens loose ends keep sketches mind future comments will tie together Bud Tenny PO Box 545 Richardson TX 75080 responding advertisers mention thatyou read aboutthem ModelAviation FF Duration/St Jean Continued page 63 concept finally evolved what now call six-times formula 6X short idea minimum weight model would have six times weight bare enginein cases would out-of-the-box weight including glow plug test 6X formula converted two old models flew 375-sq-in 099-powered job seemed about right 10 oz required 1 7-oz Cox Tee Dee 049 other 1 200-sq-in ship previously flown large powerful Schnuerle-ported 45 fitted ancient 35 having good power 7-ox engine times six equals 45 oz original weight model Both ships ajoy flymore fun have flying decades per formed about same Both bad mediocre climbs excellent glides planes noses extended retain sameor slightly forwardcenter-of-gravity time writing 17 ships have converted 6X formula have flown same results first two. have discovered proportion Gas jobs result maximum flying enjoyment Putting together up to make rules would proceecL Adoption ratio-scoring principle would help solve small-field problem thus add enjoyment would also eliminate need three site categories now structured However categories still needed solve current problems 1 RC-assist events needed totally solve small-field problem and.. 2 Some laid-back events needed please prefer slow-climbing models addition should integrate beginner events encourage newcomers providing reduced-skill events exclude experts competing simplify reduce current 90 National Record slots something manageable scribes AMA HQ Id also recommend reduction number model size-classes purposes establishing records five three matrix envision would look something like the drawing elsewhere column matrix Unlimited rules would authorize VIT have no power loading 144 Model Aviation Classic R/C Scale Puzzled CALL MAll Ibtimie build Mettdo Ill 11ev . ud know 1 Complete 2 Semi-Assembled ready ta cover sanded Call 9am- 8pm lEST 609-395-1672 Send prices Kits Engines accessories P Mitts Model Building PG lex 49 1 Stockton Dive Crunhury NJ 01512 catalogs availablo$3 Rate cards available free 5A5E 4-1/809-1/2 also build Cars Boats
Edition: Model Aviation - 1987/09
Page Numbers: 61, 144
Free Flight Indoor Bud Tenny Figure 1 trailing-edge flap HandLaunched Glider wing can lots good things discussion column STEERING PROBLEMS past 18 months steering AMA models has become increasing problemone has three sources first source has fliers have increasingly expanded scope activity up including steering La Cal Scale models second part problem has Contest Directors let either fear being bad guy because really dont understand steering rules well enough third leg problem fliers stood muttered under breaths filing protests have four comments situation 1 CDs obligation SOB ifhe needs 2 steering rules difficult under stand addition Contest Board interpretation whole matter probably will reviewed next rules cycle Figure 2 PrImary traditional Indoor wing bracing Note useof compression ribs 3 Steering works well World Champion ships because rules written environment contestant meetings before official flying begins used sure everyone understands exactly what expected 4 Steering intentional part compe tition strategy international competition AMA Indoor fliers need decide desirable philosophy AMA competition before rules can fixed have seven pages single-spaced fine print comments circulated among Bud Tenny Rick Doig Del Ogren Bob B 4 Al 4 Figure 3 Air loads braced wing explanation column Clemens ModelNet earlier 1987 concerns steering problems causes both serious business entertalning reading can already log ModelNet takes computer modem cQnnec tion via CompuServe leave message sys op Doug Pratt 767033041 asking him access data want get ModelNet call Doug AMA HQ ask him just want read data send SASE $1 Ill send copy Figure4 Secondarybracingshownonlyon side helps air loads Peanuts & Pistachios No 2 Volume 2 interesting series has dozens really great P&P photos four three-views two full-sized plans some short articles Get $495 plus $150 P&H Bill Hannan PO Box Escondido CA 92025 HLG altitude control years ago Hal Blubaugh Denver area reported interesting results using fence flap tralling edge HLG wings small strip wood glued vertically along trailing edge forming vertical flap below wing own experiments discovered glide path less critical after warps removed washout used discussed July87 column adifferentlaunchtrajectory often needed small peaked ceilings open girders possible have glider pop out almost vertical position simply fly peak girder opening calibrate placement roll-out just below girders Since Blubaugh fence will also restrict maximum launch altitude recently used limit climb Glider somewhat too heavy ceiling ran strip about Y64-in deep out within 1 tip 14-in span tapered last inch strip zero See Figure 1 sketch Figure 5 Typical competition Indoor model compression Lower tension ribs After fence added could concentrate launch placement trim roll-out easier place Glider got step quickly less problem turbu lence important everything far consistent got several seconds higher total time did fence launch placement giving away two three feet altitude bottom line model weighs over six gramsin contrast 24 grams Stan Stoy used Category record-setting Coot best single flight027contrasts over 035 best site has interesting experiment Wing bracing schemes Wing bracing Indoor models used reduce wing structure weight Figure 6 Wing post extensions new bracing replace two compression ribs employing external rigging replace wing struc tore earliest bracing consisted tether wing posts leading edgekeeping wing bowing up next advance superstructure give support agalnst loads would deflect wing downward Figure 2 shows modern version primary bracing cabane bipod supports two bracing loopsone leading edge other trailing edge Besides providing support alr ground-handling loads rigging helps hold washin washout use Figure 3 shows air loading forces wing primary bracing arrows represent forces unbraced tips Figure 7 Completely removing cabane works also info column B arrows show resulting deflection spars between bracing supports So efforts reduce spar weight carefully done avoid excessive deflections under full torque steering ceiling-scrubbing loads Figure 4 shows next logical development secondary bracing allow major spar lengths lighter undue deflection under stress extra bracing wing tip left side sketch shows tip bracing sometimes used secondary bracing Are drawbacks two bracing schemes discussed above have major disadvantage due center support point cabane Uploads downloads wing put tension wires part tension force squeezes wing spars together answer use compression ribs Figure 5 stress points extra weight compression ribs especially extra-wide FAI wings partially offsets weight savings spars Figures 2 4 show compression ribs bracing points center rib builders use Actually center rib under tension balsa bottom piece can replaced wire Continued page 144 Figure 8 Rodemsky-style bracing superstrong locks wing/motor-stick together September 1987 61 BICO PERFORMANCE 0*00 t*uNCBEII CLIORAS FROM FULL SIZE PATTERNS TOUR CHOICEI ICLUSTRATRO EACH OR SIX PACK PICK OMI SOUTORASTERO PA B BOUGHTRUB4 BITECI phies citations great gab wave recognition chance witness some premier modelers land just important us experiences cannot matched easily forgotten Mothers little pilot returns home bruised battered happy indelible memories head Envious Dont Make big broad splash next years calendar mark USFFC 1988 lay travel plans Sell Mercedes mortgage ranch thats what takes Youll glad did FF Indoor/Tenny Continued page 61 What next Figure 6 shows next develop ment Primary bracing still supports wings tip dihedral extending wing posts above spar leading edge trailing edge tip bracing work off wing posts result much stiffer wing has light spars needs two compression ribs bracing scheme gives rise comment turn fly loose inside bracing gets away must have forgotten some wires Thats still too heavy scheme shown Figure 7 used stiff posts very careful tensioning wires gets rid cabane last two compression ribs wing has two weaknesses 1 sort loose floppy move wing post must youre mounting wing 2 Tip collisions building structure make wing twist isnt bad direction Remember TII ~GRAT LAK5 40 Wing 18 25 Engines Dealers ributors Welcomed Phone 703 273-9593 FLYLINE MODELS INC P o Boo 2136 Fo,foo VIrgInie 22031 U 5 twist washes out tip opposite contact point helps tip drop turning model away obstacle ultimate Well maybe notbut like scheme shown Figure 8 close copy dozens Erv Rodemsky has done integrated wing/motor-stick bracing ex traordinarily effective Y wing posts forming triangular structure little lighter really stiff wing posts ribs top Y tension ribs same wires form tension braces extend forward hook thrust bearing rearward hook rear hook Note fuselage wires dont have tight adequately brace fuselage motor hooked up stick bends slightiy wing motor stick locked rigid structure high angle wires separation between give lot strength torsional support motor stick motor stick start collapsetuck underin high humidity able grab prop shaft thrust bearing straighten out stick working against top bracing help unhooking motor saved whole model whereas might have lost added support top bracing Thats hope ye editor will able fit whole column dozens loose ends keep sketches mind future comments will tie together Bud Tenny PO Box 545 Richardson TX 75080 responding advertisers mention thatyou read aboutthem ModelAviation FF Duration/St Jean Continued page 63 concept finally evolved what now call six-times formula 6X short idea minimum weight model would have six times weight bare enginein cases would out-of-the-box weight including glow plug test 6X formula converted two old models flew 375-sq-in 099-powered job seemed about right 10 oz required 1 7-oz Cox Tee Dee 049 other 1 200-sq-in ship previously flown large powerful Schnuerle-ported 45 fitted ancient 35 having good power 7-ox engine times six equals 45 oz original weight model Both ships ajoy flymore fun have flying decades per formed about same Both bad mediocre climbs excellent glides planes noses extended retain sameor slightly forwardcenter-of-gravity time writing 17 ships have converted 6X formula have flown same results first two. have discovered proportion Gas jobs result maximum flying enjoyment Putting together up to make rules would proceecL Adoption ratio-scoring principle would help solve small-field problem thus add enjoyment would also eliminate need three site categories now structured However categories still needed solve current problems 1 RC-assist events needed totally solve small-field problem and.. 2 Some laid-back events needed please prefer slow-climbing models addition should integrate beginner events encourage newcomers providing reduced-skill events exclude experts competing simplify reduce current 90 National Record slots something manageable scribes AMA HQ Id also recommend reduction number model size-classes purposes establishing records five three matrix envision would look something like the drawing elsewhere column matrix Unlimited rules would authorize VIT have no power loading 144 Model Aviation Classic R/C Scale Puzzled CALL MAll Ibtimie build Mettdo Ill 11ev . ud know 1 Complete 2 Semi-Assembled ready ta cover sanded Call 9am- 8pm lEST 609-395-1672 Send prices Kits Engines accessories P Mitts Model Building PG lex 49 1 Stockton Dive Crunhury NJ 01512 catalogs availablo$3 Rate cards available free 5A5E 4-1/809-1/2 also build Cars Boats