400-HP 4000 LB 400 MPH General Hap Arnolds cute little formula lightweight fighter plane As top man US Army Air Forces World War II com manded lot attention Moreover idea very light simple fighter broad appeal time still does problem doesnt seem way Sure lot fighters start out light weights realities combat faced weight goes up size has go up handle weight Pretty soon clever little airplane has become just another big complicated machine classic example good idea can go sour Bell XP-77 have small empty weight under 3000 lb little engine 500-hp V-12 simple design drawback didnt work Its performance far below what Bell Aircraft promised Furthermore took twice long bring flying status did first American jet built same time Bell terrific idea sure fact XP 77 inspired exciting air planes ever seen French Caudron C460 Michel Detroyat dominated 1936 Los Angeles National Air Races Any airplane sleek efficient Caudron its background should have winner theres big dif ference between racing planes combat planes September 1936 US Army Air Corps Gen Henry Hap Arnold sent test pilots Ben Kelsey Los Angeles take look sensational Caudron see would possible create fighter like Kelsey now deceased spent last days historian National Air Space Museum did told highly impressed little French racer broken Thompson Trophy Race speed record despite having half cubic inches previous record holder As racer all-time greats see might turned military airplane First would need larger wheels tires could operate grass runways would mean thicker heavier wing retract landing gear would cut speed Next would have carry lot fuel plus few machine guns armor plating understandably absent racer Suddenly racer weighed 1300 lb empty would well over 2000 lb growing happens wing area would have increased lift extra weight beefing up structure would necessary would have horsepower pull would bring weight would mean wing area etc etc Caudrons superb streamlining would have get same treatment Its canopy desned speed order give fighter pilot chance see might shooting him canopy would have raised lot glass added drag weight would come guns aerials bomb shackles added Maintenance another problem wasnt quite obvious racer no access holes inspection minor repairs lot would have installed along weight parts moved around make easier work under wartime conditions Ben Kelsey got back Wright Field reported Arnold Caudron modified make fighter its numbers dimensions weight power came out very interesting way modified racer resem July 198241 GRA TEFUL THANKS TO DON BERLINER FOR RESEARCI-FING DETAILED INFORMATION INCLUDED HERE ATHERINEII E CASSITY OF THE AIR FORCE MUSEUM WHO SUPPLIED ADDITIONAL MA TERIAL Ar EXTREMELY SHORT NOTICE C I1671 AIRFOIL SECTIONS AT ROOT TIP 6F NACA LOW- DRAG WING VALUES ARE PERCENTAGES OF CHO ROOT SECTION ONLY IS SYMMETRICAL * REAR LIGHT UE VIEW ON TORQUE LINKS 0 BOTH AIRCRAFT WERE ALUMINUM OVERALL WITH SERIALS ETC BLACK COLOURS OF FUSELAGE S RUDDER STRIPING TO 43-34975 NOT KNOWN DETAILS LANDING GEAR RETRACTING MECHANISM NOT KNOWN DATA WINGSPAN WING AREA10011 ASPECT RATIOZ5 OVERALL LENGTH 22-A STABILIZER SPAN -WHEEL TRACK C PROPELLER DIA --- 9-d EMPTY WEIGHT-- 2855 DESIGN lb 43-349 GROSS WEIGHT 3583 lb 43-3 \ 43-34976 SECTIONS C OIL COOLER VENT ING GILLS ING GILLS SNOWN OPEN 975 & 9167 INTERNAL DETAILS APE APPROXIMATE JRUE V7EW ON TORQUE LINKS 3J MODIFICATIONS TO COVER DOORS INCLUDE SECOND JOINT TO HINGED UPPER PANEL REMOVAL OF NARROW BOTTOM SEGMENT 54 LEFT MAIN LEG FULLY EXTENDED NO LOAD AULIC LINE OMITTEDKIT NOTE VARIATION IN TAILCONE PROFILES 6 TORQUE LINKS OMITTED 3 NOSE WHEEL LEG FULLY EXTENDEO NO LOAD ANOPY ROTATES AFT IN SIDE FUSELAGE COCKPIT DETAILS NOT KNOWN 43-3491IE COOLING GILLS SIMILAR ON LEFT SIDESEE DETAIL OIL COOLER EXIT DUCT SIMILAR ON 43-34975 AT ROLL-OUT BOTH AIRCRAFT CARRIED INSIGNIA SERIAL NLII7BER NUMEROUS STENCILLED NOTICES ON FUSELAGE ID N 42 Model Aviation AERO PROQUCTS PROPELLER BLADE 3 MATT BLACK BLADE YELLOW TIP ROOT SCCT1ON NACA 65 2-017 STAT/Oil 06D1M412 0 0 51277 7551512 p251408 252664 503764 754586 105264 iS6330 207130 255 7705 50 8125 358381 408495 456434 50 0152 55 7629 60 6903 65 6000 70 4986 75 3976 80*2936 85 1909 90 1043 95 361 1000 X-X Y rip SECTION NACA 67-CI3j15 UPPER SURFACE LOWER SURFACE STATION ORDINATE STATION RDiNAT 0000 422 1209378 1129 663 1450837 1340 1151-8451351675 2392547261-2245 4883504515 -2996 737424 7763 3559 9-87485510134013 148858401319-4736 198965970115281 249072082510-5722 299276733000-6051 346480225506-6296 399682634004-6463 449883934502-654 9 500084265000-6566 5302834254986490 6005812559956351 650877526492-6046 701171886909-5620 751462817487-4927 8012506179883 965 850936668491-2850 900622078965-1677 95028649498 614 10001000 II SIGHT 3 2------ ROOT SEC77ON OHCo 15 66CH0R0 NACA 652-017 030-EzII7~7IIjTIP SECTION s3J 22 CHORD HACA 67I-1315 COCKPIT VENTILATION X SECTIONS ON COOLING GILLS Co 2 WiNG-TIP piror oi 4334916 CoJ F ELEVATOR TRIM TAB CONTROL SORN Co 3 PITOT 6 F6JRING 01 4334915 o3 p AILERON TAB o3 RUDDER TAB o3 6-8F-9 MAX WiDTH OP 17LLET TTFf 5FT6F17F-8 ENLARGED DETAILS CoL5 l5o GIVEN SCALE o22o Co33o PITOT TUBE MACHINE GUN 6 CAMERA PORTS WERE NOT INSTALLED ON 43-34915 IIN AWEL J SCAI.E BELL AIRCRAFT CORP TR14 D-6 3349I5 COOLING GILLS SIMILAR ON RIGHT SIDE SEE DETAIL REAR LETT COWL PANEL SIMILAR ON 43-34916 J4p 1982 U SAAF BELL XP77 MODEL AVIATION July 198243 little wooden Bell novel ideas turned hardware heat World War II Like others took long nft rd fighters day just faded away bled academic way Curtiss P-36 Air Corps already having built course C460 doesnt look bit like Curtiss P-36 military version would have about same size power performance So much brainstorm basic idea lightweight fighter didnt die fact several months before debut Caudron Los Angeles Bell Aircraft Co begun design work novel lightweight pursuit plane would have its engine middle its propeller driven long extension shaft What become P-39 Aircobra ordered Air Corps 1937 first flew early 1939 P-39 weighed under 4000 lb empty qualifying lightweight though hardly small Caudron Racer As often case Airacobra grew production prototype weighed over 4500 lb first YP-39 up 5000 lb time first airplanes delivered Air Corps squadrons P-39Ds empty weight up almost 5500 lb Hack drawing ~d.. few months after P-39 entered service early 1941 Gen Arnold back 400-hp 4000 lb 400 mph idea design work began Bell what first called Tri-4 light highly maneuver able interceptor According final report project Tri-4 airplane proposed Bell have high speed 410 mph 27000 feet 500-hp equipped supercharged Ranger XV-770-9 engine Its design gross weight about 3700 lb carry 22mm cannon firing through propeller hub addition two 50-caliber synchronized nose guns airfoil laminar flow type May 16 1942 initial batch 25 air planes ordered Two weeks later Bell sug gested building six airplanes shortage engines total cost including profit set just under $500000 first airplane delivered within six months sixth January 1943 Tri-4 work out promised Bell perhaps lightweight fighter would reality things rarely go smoothly June 1942 Air Corps decided airplane should built wood conserve scarce alumi num much came areas being oc cupied Japanese Bell realized Continued page 132 44 Model Aviation truly BIG PuTS S-2A want superb 135 scale biplane kit features easy-to-build Snap-Lock construction numbered die-cut hand-machined balsa hardwood parts vacuum-formed cowl wheel pants clear windscreen neces sary hardware color decals full-size plans photo building guide radio installation directions List Price$32995 E&R Price$21995 BELLANCA DECATHLON top quality kit Pilot has wingspan 96/3 1519 sq area 60 long Kit features numbered die-cut hand-machined parts pre-cut window 3-dimensional instrument panel fullsized plans photo building guide pre-formed cowl wheel pants plus much List Price$30495 E&R Price$22995 NEW Bellanca Decathlon 40 same /4-scale kit above smaller has wingspan 67/4 774 sq wing area designed fly 40- 60-size engine List Price$13995 E&R Price$10695 FUTABA 6-FP-6FN radio complete standard charger including ERR special heavy-duty /4-scale pack age includes 4 large servos produce 154 oz torque 1 standard S-26 servo use throttle control also include heavy-duty 1800 MAH battery pack List Price$46990 E&R Price$32999 R R 1 Box 10 ______ Edgeley ND 58433 701/493-2015~obbieS PRODUCTS Complete Line Exhaust Systems * Tuned Pipes * Muffled Tuned Pipes * Headers * Venturi Mufflers * Expansion Mufflers Helicopter Ball Mufflers ialized Exhaust Systems Unsurpassed Worh~ h Pqrformance Nate 5 7208 7224 7240 7564 MHz Nate 6 See sec 2106 Commissions Rules Nate 7 NG49 following frequencies may autharized low-power 1 watt input mobile operations radio services shown subject condition no inter ference caused reception television stations operating channels 4 5 Manufacturers Radio Service MHZMHzMHzMHZMHZ 7202 7210 7218 7226 7234 7204 7212 7220 7228 7236 7206 7214 7222 7230 7238 7208 7216 7224 7232 7240 Special Industrial Radio Service Manufacturers Radio Service Railroad Radio Service MHz MHz MHz MHZ MHZ 7244 7252 7260 7548 7556 724d 7256 7544 7552 7560 Nate 8 NG56 Th frequencies 7208 7216 7224 7232 7240 7296 7564 MHz may authorized low power 1-watt put mobile operations Personal Radio Services radio control models subject condition interference will caused remote control industrial equip ment operating same adjacent fre quencies reception television stations operating Channels 4 5 TV terference shall considered occur ever reception regularly used television signals Impaired destroyed regardless strength television signais distance television station Note 9 No doubt reason Academy has requested access band segment 7586-7600 MHZ Bell XP-77/Berliner Continued paoe 44 tough would switch materials probably would have quit spot late June design gross weight up pqfl performance ysrem TOP PERFORMANCE K&B ENGINES 16 Airplane 4 Marine K&B FUELSK&B GLOW PLUGS 7 Blends4 choices Matched Finish System BEST APPEARANCE K&B FIBERGLASS CLOTH K&B Micro-Balloons FILLER K&B SUPER POXY RESIN KAB SUPER POSY THINNER K&B SUPER POSY PRIMER K&9 SUPER FOXY PAINT K&B MIXING CUPS 3650 lb still within plans Arnolds formula high wing loading would mean such long takeoff run decided cut structure gross weight 3000 lb Already price tag up $700000 end sight January 1943 six airplanes supposed have delivered Bell told Air Corps serious complications arisen efforts build high-speed airplane wood aiming July delivery first airplanes others end year schedule almost year off cost project up S2 million Bell blamed slippage need sub contract wood construction companies werent already loaded work troopcarrying gliders major friction tween Bell its subcontractors matters quality inspection working drawings top off Ranger engine having cooling troubles May 1943 serious thought given dumping entire XP-77 project because Bell couldnt concentrate- enough effort company too busy its P-63 Kingcobra very secret P-59 Airacomet jet flown first time October 1942 Finally Air Corps decided cancel thing first two prototypes felt would useful obtainingvaluable flight data type plywood aircraft troubles came light Bell stopped inspecting production factory Goshen Indiana Veneer Co building wings Air Corps help Bell discovered Goshen built set test wings no flight wings November 1943 Vidal Research Corp built both 132 Model Aviation scale Pitts S2A Pilot Kit Scale Flight u-uzu GEARED PROP DRIVE Swing Big Prop Realistic RPM Its she2 Ooncs Piop $1950 eKII-107 Con Pee Wee 020o 020 ,II sog 7-4 0-4 prOp 4 roabstcJeibcerrt sc4e IligOl KRESS TECHNOLOGY INC 27 Mdi Road IEI 6 11PM Lloyd i-lan,, N V 11743 00 /Ditibot inqokie ore lenited ZONA SAWS The one wood handle good blade Razor #200 $210 Sabre * 400 -$185 Sa100-389 Replacement blades available yosr dealer ModeS SupplyPO Box 3957 A 90510 uSA Super Mini Boy Recommended Eigines Radios- Mufflers Helicopter tools stock Worlds stable easiest fly small 40 size R/O Helicopter Low maintenance mechanics engineer ed Dieter Schiuter Father RIO Helicopters Features fully collective Bell mixing main rotor head upright spinner starting straight shaft driven tail rotor & automatic compensation symmet rical prebuilt main rotor tail rotor blades autorotation clutch Uses standard 4 chanel radio Kits parts stock guarantee helicopters fly Ask man flies Move up Schiuter inSifrp U SEAN IflG subsidiary MINIATURE AIRCRAFT 2594 North Orange Blossom Trail ndo FL 32804 Phone 30514224531 test fuselages six flight fuselages high-altitude version Ranger V- 12 seriously delayed XP-77 use low-altitude engine its performance would inferior fighter airplane comparison existing models now production ac cording USAAF Technical Report #5359 Vidal Research took over job building wings made schedule slip Problems arose over matters basic time needed spread glue Completion first airplane delayed February 1944 Marcfr would make almost 1 years late wasnt until April Fools Day 1944 XP-77 flew Bells Niagra Falls NY factory Success last Far proto type arrived Wright Field May 2 soon revealed serious vibration 1700 rpm 2300 rpm probably due lack shock absorbers engine mounts June 6 1944 Allied troops storming Nor mandy beaches final assault Nazi-held Europe USAAF got around giving prototype XP-77 its serial number 43-34915 Official flight tests carried out Eglin Field FL second XP-77 43-34916 starting late July 1944 October 2 airplane fell out Immelmann turn inverted spin pilot recovered air plane went upright flat spin could recover forced jump pilot landed safely airplane demolished proved last straw project ended December 2 March 1945 war drawing close Army Air Forces completed report Flight Tests Bell XP-77 Airplane following has excerpted general handling characteristics XP-77 airplane satisfactory although restric tions evented dives spins violent maneuvers jectionable feature control system fixed trim tabs ailerons rudder results condition flight airplane will fly stick- rudder-free ground setting the. tabs Visibility good conditions flight ground handling Noise vibration cockpit considerable cockpit becomes very cold uncomfortable cold weather high altitude cockpit heat available high speed 328 mph obtained military power 3150 rpm 416 mani fold pressure 12600 ft critical altitude high speed 330 mph obtained war emergencypower 3300 rpm and57 at4000 ft critical altitude maximum rate climb obtained war emergency power 3630 feet per minute critical altitude 2000 ft ConclusionsThe overall performance XP-77 airplane inferior present fighter aircraft employed AAF results flight tests considerably lower estimated performance set Bell Aircraft Corp maximum speed airplane war emergency power considerably lower other AAF interceptor aircraft operating military power maximum rate climb military power very low interceptor air craft low service ceiling airplane renders useless against high altitude aircraft bad XP-77 fell 90 mph short its promised top speed rate climb no better 200-hp Pins Special aerobatic biplane service ceiling 30000 ft era P-38s would go 39000 ft P 51s would top 40000 ft interesting idea didnt work taught its creators lesson very very difficult build truly lightweight fighter plane General Dynamics learning lesson over again its F- 16 no longer lightweight Mach 2 ter course doesnt make sense give up such worthy goal As matter fact start Cassutt will close 250 mph 135-hp weighing little over 500 lb add couple machine guns some fuel radio two ours/Hill Continued page 80 other useful ingredients avoid building wing spar might dis solve its contents during flight samples balsa coated variety resins placed baby food jars containing candidate fuels array samples stored months backyard greenhouse exposure thermal cycling solvents brutal test Some combinations looked satisfactory dur ing winter turned messes July Sig Mfg Cos polyester finishing resin eventually chosen K&B finishing resin fared equally well test Scale modelers using chainsaw engines might find idea useful Its OK gasoline havent found resins will resist fuels containing nitromethane ether Engine modifications OS F560 engine received designed use glow plug ignition regular alcohol-based model fuel Gasoline far efficient alcohol glow plug ignition doesnt work well gasoline based fuels unless compression ratio increased point mechanical problems July 1982 133
Edition: Model Aviation - 1982/07
Page Numbers: 41, 42, 43, 44, 132, 133
400-HP 4000 LB 400 MPH General Hap Arnolds cute little formula lightweight fighter plane As top man US Army Air Forces World War II com manded lot attention Moreover idea very light simple fighter broad appeal time still does problem doesnt seem way Sure lot fighters start out light weights realities combat faced weight goes up size has go up handle weight Pretty soon clever little airplane has become just another big complicated machine classic example good idea can go sour Bell XP-77 have small empty weight under 3000 lb little engine 500-hp V-12 simple design drawback didnt work Its performance far below what Bell Aircraft promised Furthermore took twice long bring flying status did first American jet built same time Bell terrific idea sure fact XP 77 inspired exciting air planes ever seen French Caudron C460 Michel Detroyat dominated 1936 Los Angeles National Air Races Any airplane sleek efficient Caudron its background should have winner theres big dif ference between racing planes combat planes September 1936 US Army Air Corps Gen Henry Hap Arnold sent test pilots Ben Kelsey Los Angeles take look sensational Caudron see would possible create fighter like Kelsey now deceased spent last days historian National Air Space Museum did told highly impressed little French racer broken Thompson Trophy Race speed record despite having half cubic inches previous record holder As racer all-time greats see might turned military airplane First would need larger wheels tires could operate grass runways would mean thicker heavier wing retract landing gear would cut speed Next would have carry lot fuel plus few machine guns armor plating understandably absent racer Suddenly racer weighed 1300 lb empty would well over 2000 lb growing happens wing area would have increased lift extra weight beefing up structure would necessary would have horsepower pull would bring weight would mean wing area etc etc Caudrons superb streamlining would have get same treatment Its canopy desned speed order give fighter pilot chance see might shooting him canopy would have raised lot glass added drag weight would come guns aerials bomb shackles added Maintenance another problem wasnt quite obvious racer no access holes inspection minor repairs lot would have installed along weight parts moved around make easier work under wartime conditions Ben Kelsey got back Wright Field reported Arnold Caudron modified make fighter its numbers dimensions weight power came out very interesting way modified racer resem July 198241 GRA TEFUL THANKS TO DON BERLINER FOR RESEARCI-FING DETAILED INFORMATION INCLUDED HERE ATHERINEII E CASSITY OF THE AIR FORCE MUSEUM WHO SUPPLIED ADDITIONAL MA TERIAL Ar EXTREMELY SHORT NOTICE C I1671 AIRFOIL SECTIONS AT ROOT TIP 6F NACA LOW- DRAG WING VALUES ARE PERCENTAGES OF CHO ROOT SECTION ONLY IS SYMMETRICAL * REAR LIGHT UE VIEW ON TORQUE LINKS 0 BOTH AIRCRAFT WERE ALUMINUM OVERALL WITH SERIALS ETC BLACK COLOURS OF FUSELAGE S RUDDER STRIPING TO 43-34975 NOT KNOWN DETAILS LANDING GEAR RETRACTING MECHANISM NOT KNOWN DATA WINGSPAN WING AREA10011 ASPECT RATIOZ5 OVERALL LENGTH 22-A STABILIZER SPAN -WHEEL TRACK C PROPELLER DIA --- 9-d EMPTY WEIGHT-- 2855 DESIGN lb 43-349 GROSS WEIGHT 3583 lb 43-3 \ 43-34976 SECTIONS C OIL COOLER VENT ING GILLS ING GILLS SNOWN OPEN 975 & 9167 INTERNAL DETAILS APE APPROXIMATE JRUE V7EW ON TORQUE LINKS 3J MODIFICATIONS TO COVER DOORS INCLUDE SECOND JOINT TO HINGED UPPER PANEL REMOVAL OF NARROW BOTTOM SEGMENT 54 LEFT MAIN LEG FULLY EXTENDED NO LOAD AULIC LINE OMITTEDKIT NOTE VARIATION IN TAILCONE PROFILES 6 TORQUE LINKS OMITTED 3 NOSE WHEEL LEG FULLY EXTENDEO NO LOAD ANOPY ROTATES AFT IN SIDE FUSELAGE COCKPIT DETAILS NOT KNOWN 43-3491IE COOLING GILLS SIMILAR ON LEFT SIDESEE DETAIL OIL COOLER EXIT DUCT SIMILAR ON 43-34975 AT ROLL-OUT BOTH AIRCRAFT CARRIED INSIGNIA SERIAL NLII7BER NUMEROUS STENCILLED NOTICES ON FUSELAGE ID N 42 Model Aviation AERO PROQUCTS PROPELLER BLADE 3 MATT BLACK BLADE YELLOW TIP ROOT SCCT1ON NACA 65 2-017 STAT/Oil 06D1M412 0 0 51277 7551512 p251408 252664 503764 754586 105264 iS6330 207130 255 7705 50 8125 358381 408495 456434 50 0152 55 7629 60 6903 65 6000 70 4986 75 3976 80*2936 85 1909 90 1043 95 361 1000 X-X Y rip SECTION NACA 67-CI3j15 UPPER SURFACE LOWER SURFACE STATION ORDINATE STATION RDiNAT 0000 422 1209378 1129 663 1450837 1340 1151-8451351675 2392547261-2245 4883504515 -2996 737424 7763 3559 9-87485510134013 148858401319-4736 198965970115281 249072082510-5722 299276733000-6051 346480225506-6296 399682634004-6463 449883934502-654 9 500084265000-6566 5302834254986490 6005812559956351 650877526492-6046 701171886909-5620 751462817487-4927 8012506179883 965 850936668491-2850 900622078965-1677 95028649498 614 10001000 II SIGHT 3 2------ ROOT SEC77ON OHCo 15 66CH0R0 NACA 652-017 030-EzII7~7IIjTIP SECTION s3J 22 CHORD HACA 67I-1315 COCKPIT VENTILATION X SECTIONS ON COOLING GILLS Co 2 WiNG-TIP piror oi 4334916 CoJ F ELEVATOR TRIM TAB CONTROL SORN Co 3 PITOT 6 F6JRING 01 4334915 o3 p AILERON TAB o3 RUDDER TAB o3 6-8F-9 MAX WiDTH OP 17LLET TTFf 5FT6F17F-8 ENLARGED DETAILS CoL5 l5o GIVEN SCALE o22o Co33o PITOT TUBE MACHINE GUN 6 CAMERA PORTS WERE NOT INSTALLED ON 43-34915 IIN AWEL J SCAI.E BELL AIRCRAFT CORP TR14 D-6 3349I5 COOLING GILLS SIMILAR ON RIGHT SIDE SEE DETAIL REAR LETT COWL PANEL SIMILAR ON 43-34916 J4p 1982 U SAAF BELL XP77 MODEL AVIATION July 198243 little wooden Bell novel ideas turned hardware heat World War II Like others took long nft rd fighters day just faded away bled academic way Curtiss P-36 Air Corps already having built course C460 doesnt look bit like Curtiss P-36 military version would have about same size power performance So much brainstorm basic idea lightweight fighter didnt die fact several months before debut Caudron Los Angeles Bell Aircraft Co begun design work novel lightweight pursuit plane would have its engine middle its propeller driven long extension shaft What become P-39 Aircobra ordered Air Corps 1937 first flew early 1939 P-39 weighed under 4000 lb empty qualifying lightweight though hardly small Caudron Racer As often case Airacobra grew production prototype weighed over 4500 lb first YP-39 up 5000 lb time first airplanes delivered Air Corps squadrons P-39Ds empty weight up almost 5500 lb Hack drawing ~d.. few months after P-39 entered service early 1941 Gen Arnold back 400-hp 4000 lb 400 mph idea design work began Bell what first called Tri-4 light highly maneuver able interceptor According final report project Tri-4 airplane proposed Bell have high speed 410 mph 27000 feet 500-hp equipped supercharged Ranger XV-770-9 engine Its design gross weight about 3700 lb carry 22mm cannon firing through propeller hub addition two 50-caliber synchronized nose guns airfoil laminar flow type May 16 1942 initial batch 25 air planes ordered Two weeks later Bell sug gested building six airplanes shortage engines total cost including profit set just under $500000 first airplane delivered within six months sixth January 1943 Tri-4 work out promised Bell perhaps lightweight fighter would reality things rarely go smoothly June 1942 Air Corps decided airplane should built wood conserve scarce alumi num much came areas being oc cupied Japanese Bell realized Continued page 132 44 Model Aviation truly BIG PuTS S-2A want superb 135 scale biplane kit features easy-to-build Snap-Lock construction numbered die-cut hand-machined balsa hardwood parts vacuum-formed cowl wheel pants clear windscreen neces sary hardware color decals full-size plans photo building guide radio installation directions List Price$32995 E&R Price$21995 BELLANCA DECATHLON top quality kit Pilot has wingspan 96/3 1519 sq area 60 long Kit features numbered die-cut hand-machined parts pre-cut window 3-dimensional instrument panel fullsized plans photo building guide pre-formed cowl wheel pants plus much List Price$30495 E&R Price$22995 NEW Bellanca Decathlon 40 same /4-scale kit above smaller has wingspan 67/4 774 sq wing area designed fly 40- 60-size engine List Price$13995 E&R Price$10695 FUTABA 6-FP-6FN radio complete standard charger including ERR special heavy-duty /4-scale pack age includes 4 large servos produce 154 oz torque 1 standard S-26 servo use throttle control also include heavy-duty 1800 MAH battery pack List Price$46990 E&R Price$32999 R R 1 Box 10 ______ Edgeley ND 58433 701/493-2015~obbieS PRODUCTS Complete Line Exhaust Systems * Tuned Pipes * Muffled Tuned Pipes * Headers * Venturi Mufflers * Expansion Mufflers Helicopter Ball Mufflers ialized Exhaust Systems Unsurpassed Worh~ h Pqrformance Nate 5 7208 7224 7240 7564 MHz Nate 6 See sec 2106 Commissions Rules Nate 7 NG49 following frequencies may autharized low-power 1 watt input mobile operations radio services shown subject condition no inter ference caused reception television stations operating channels 4 5 Manufacturers Radio Service MHZMHzMHzMHZMHZ 7202 7210 7218 7226 7234 7204 7212 7220 7228 7236 7206 7214 7222 7230 7238 7208 7216 7224 7232 7240 Special Industrial Radio Service Manufacturers Radio Service Railroad Radio Service MHz MHz MHz MHZ MHZ 7244 7252 7260 7548 7556 724d 7256 7544 7552 7560 Nate 8 NG56 Th frequencies 7208 7216 7224 7232 7240 7296 7564 MHz may authorized low power 1-watt put mobile operations Personal Radio Services radio control models subject condition interference will caused remote control industrial equip ment operating same adjacent fre quencies reception television stations operating Channels 4 5 TV terference shall considered occur ever reception regularly used television signals Impaired destroyed regardless strength television signais distance television station Note 9 No doubt reason Academy has requested access band segment 7586-7600 MHZ Bell XP-77/Berliner Continued paoe 44 tough would switch materials probably would have quit spot late June design gross weight up pqfl performance ysrem TOP PERFORMANCE K&B ENGINES 16 Airplane 4 Marine K&B FUELSK&B GLOW PLUGS 7 Blends4 choices Matched Finish System BEST APPEARANCE K&B FIBERGLASS CLOTH K&B Micro-Balloons FILLER K&B SUPER POXY RESIN KAB SUPER POSY THINNER K&B SUPER POSY PRIMER K&9 SUPER FOXY PAINT K&B MIXING CUPS 3650 lb still within plans Arnolds formula high wing loading would mean such long takeoff run decided cut structure gross weight 3000 lb Already price tag up $700000 end sight January 1943 six airplanes supposed have delivered Bell told Air Corps serious complications arisen efforts build high-speed airplane wood aiming July delivery first airplanes others end year schedule almost year off cost project up S2 million Bell blamed slippage need sub contract wood construction companies werent already loaded work troopcarrying gliders major friction tween Bell its subcontractors matters quality inspection working drawings top off Ranger engine having cooling troubles May 1943 serious thought given dumping entire XP-77 project because Bell couldnt concentrate- enough effort company too busy its P-63 Kingcobra very secret P-59 Airacomet jet flown first time October 1942 Finally Air Corps decided cancel thing first two prototypes felt would useful obtainingvaluable flight data type plywood aircraft troubles came light Bell stopped inspecting production factory Goshen Indiana Veneer Co building wings Air Corps help Bell discovered Goshen built set test wings no flight wings November 1943 Vidal Research Corp built both 132 Model Aviation scale Pitts S2A Pilot Kit Scale Flight u-uzu GEARED PROP DRIVE Swing Big Prop Realistic RPM Its she2 Ooncs Piop $1950 eKII-107 Con Pee Wee 020o 020 ,II sog 7-4 0-4 prOp 4 roabstcJeibcerrt sc4e IligOl KRESS TECHNOLOGY INC 27 Mdi Road IEI 6 11PM Lloyd i-lan,, N V 11743 00 /Ditibot inqokie ore lenited ZONA SAWS The one wood handle good blade Razor #200 $210 Sabre * 400 -$185 Sa100-389 Replacement blades available yosr dealer ModeS SupplyPO Box 3957 A 90510 uSA Super Mini Boy Recommended Eigines Radios- Mufflers Helicopter tools stock Worlds stable easiest fly small 40 size R/O Helicopter Low maintenance mechanics engineer ed Dieter Schiuter Father RIO Helicopters Features fully collective Bell mixing main rotor head upright spinner starting straight shaft driven tail rotor & automatic compensation symmet rical prebuilt main rotor tail rotor blades autorotation clutch Uses standard 4 chanel radio Kits parts stock guarantee helicopters fly Ask man flies Move up Schiuter inSifrp U SEAN IflG subsidiary MINIATURE AIRCRAFT 2594 North Orange Blossom Trail ndo FL 32804 Phone 30514224531 test fuselages six flight fuselages high-altitude version Ranger V- 12 seriously delayed XP-77 use low-altitude engine its performance would inferior fighter airplane comparison existing models now production ac cording USAAF Technical Report #5359 Vidal Research took over job building wings made schedule slip Problems arose over matters basic time needed spread glue Completion first airplane delayed February 1944 Marcfr would make almost 1 years late wasnt until April Fools Day 1944 XP-77 flew Bells Niagra Falls NY factory Success last Far proto type arrived Wright Field May 2 soon revealed serious vibration 1700 rpm 2300 rpm probably due lack shock absorbers engine mounts June 6 1944 Allied troops storming Nor mandy beaches final assault Nazi-held Europe USAAF got around giving prototype XP-77 its serial number 43-34915 Official flight tests carried out Eglin Field FL second XP-77 43-34916 starting late July 1944 October 2 airplane fell out Immelmann turn inverted spin pilot recovered air plane went upright flat spin could recover forced jump pilot landed safely airplane demolished proved last straw project ended December 2 March 1945 war drawing close Army Air Forces completed report Flight Tests Bell XP-77 Airplane following has excerpted general handling characteristics XP-77 airplane satisfactory although restric tions evented dives spins violent maneuvers jectionable feature control system fixed trim tabs ailerons rudder results condition flight airplane will fly stick- rudder-free ground setting the. tabs Visibility good conditions flight ground handling Noise vibration cockpit considerable cockpit becomes very cold uncomfortable cold weather high altitude cockpit heat available high speed 328 mph obtained military power 3150 rpm 416 mani fold pressure 12600 ft critical altitude high speed 330 mph obtained war emergencypower 3300 rpm and57 at4000 ft critical altitude maximum rate climb obtained war emergency power 3630 feet per minute critical altitude 2000 ft ConclusionsThe overall performance XP-77 airplane inferior present fighter aircraft employed AAF results flight tests considerably lower estimated performance set Bell Aircraft Corp maximum speed airplane war emergency power considerably lower other AAF interceptor aircraft operating military power maximum rate climb military power very low interceptor air craft low service ceiling airplane renders useless against high altitude aircraft bad XP-77 fell 90 mph short its promised top speed rate climb no better 200-hp Pins Special aerobatic biplane service ceiling 30000 ft era P-38s would go 39000 ft P 51s would top 40000 ft interesting idea didnt work taught its creators lesson very very difficult build truly lightweight fighter plane General Dynamics learning lesson over again its F- 16 no longer lightweight Mach 2 ter course doesnt make sense give up such worthy goal As matter fact start Cassutt will close 250 mph 135-hp weighing little over 500 lb add couple machine guns some fuel radio two ours/Hill Continued page 80 other useful ingredients avoid building wing spar might dis solve its contents during flight samples balsa coated variety resins placed baby food jars containing candidate fuels array samples stored months backyard greenhouse exposure thermal cycling solvents brutal test Some combinations looked satisfactory dur ing winter turned messes July Sig Mfg Cos polyester finishing resin eventually chosen K&B finishing resin fared equally well test Scale modelers using chainsaw engines might find idea useful Its OK gasoline havent found resins will resist fuels containing nitromethane ether Engine modifications OS F560 engine received designed use glow plug ignition regular alcohol-based model fuel Gasoline far efficient alcohol glow plug ignition doesnt work well gasoline based fuels unless compression ratio increased point mechanical problems July 1982 133
Edition: Model Aviation - 1982/07
Page Numbers: 41, 42, 43, 44, 132, 133
400-HP 4000 LB 400 MPH General Hap Arnolds cute little formula lightweight fighter plane As top man US Army Air Forces World War II com manded lot attention Moreover idea very light simple fighter broad appeal time still does problem doesnt seem way Sure lot fighters start out light weights realities combat faced weight goes up size has go up handle weight Pretty soon clever little airplane has become just another big complicated machine classic example good idea can go sour Bell XP-77 have small empty weight under 3000 lb little engine 500-hp V-12 simple design drawback didnt work Its performance far below what Bell Aircraft promised Furthermore took twice long bring flying status did first American jet built same time Bell terrific idea sure fact XP 77 inspired exciting air planes ever seen French Caudron C460 Michel Detroyat dominated 1936 Los Angeles National Air Races Any airplane sleek efficient Caudron its background should have winner theres big dif ference between racing planes combat planes September 1936 US Army Air Corps Gen Henry Hap Arnold sent test pilots Ben Kelsey Los Angeles take look sensational Caudron see would possible create fighter like Kelsey now deceased spent last days historian National Air Space Museum did told highly impressed little French racer broken Thompson Trophy Race speed record despite having half cubic inches previous record holder As racer all-time greats see might turned military airplane First would need larger wheels tires could operate grass runways would mean thicker heavier wing retract landing gear would cut speed Next would have carry lot fuel plus few machine guns armor plating understandably absent racer Suddenly racer weighed 1300 lb empty would well over 2000 lb growing happens wing area would have increased lift extra weight beefing up structure would necessary would have horsepower pull would bring weight would mean wing area etc etc Caudrons superb streamlining would have get same treatment Its canopy desned speed order give fighter pilot chance see might shooting him canopy would have raised lot glass added drag weight would come guns aerials bomb shackles added Maintenance another problem wasnt quite obvious racer no access holes inspection minor repairs lot would have installed along weight parts moved around make easier work under wartime conditions Ben Kelsey got back Wright Field reported Arnold Caudron modified make fighter its numbers dimensions weight power came out very interesting way modified racer resem July 198241 GRA TEFUL THANKS TO DON BERLINER FOR RESEARCI-FING DETAILED INFORMATION INCLUDED HERE ATHERINEII E CASSITY OF THE AIR FORCE MUSEUM WHO SUPPLIED ADDITIONAL MA TERIAL Ar EXTREMELY SHORT NOTICE C I1671 AIRFOIL SECTIONS AT ROOT TIP 6F NACA LOW- DRAG WING VALUES ARE PERCENTAGES OF CHO ROOT SECTION ONLY IS SYMMETRICAL * REAR LIGHT UE VIEW ON TORQUE LINKS 0 BOTH AIRCRAFT WERE ALUMINUM OVERALL WITH SERIALS ETC BLACK COLOURS OF FUSELAGE S RUDDER STRIPING TO 43-34975 NOT KNOWN DETAILS LANDING GEAR RETRACTING MECHANISM NOT KNOWN DATA WINGSPAN WING AREA10011 ASPECT RATIOZ5 OVERALL LENGTH 22-A STABILIZER SPAN -WHEEL TRACK C PROPELLER DIA --- 9-d EMPTY WEIGHT-- 2855 DESIGN lb 43-349 GROSS WEIGHT 3583 lb 43-3 \ 43-34976 SECTIONS C OIL COOLER VENT ING GILLS ING GILLS SNOWN OPEN 975 & 9167 INTERNAL DETAILS APE APPROXIMATE JRUE V7EW ON TORQUE LINKS 3J MODIFICATIONS TO COVER DOORS INCLUDE SECOND JOINT TO HINGED UPPER PANEL REMOVAL OF NARROW BOTTOM SEGMENT 54 LEFT MAIN LEG FULLY EXTENDED NO LOAD AULIC LINE OMITTEDKIT NOTE VARIATION IN TAILCONE PROFILES 6 TORQUE LINKS OMITTED 3 NOSE WHEEL LEG FULLY EXTENDEO NO LOAD ANOPY ROTATES AFT IN SIDE FUSELAGE COCKPIT DETAILS NOT KNOWN 43-3491IE COOLING GILLS SIMILAR ON LEFT SIDESEE DETAIL OIL COOLER EXIT DUCT SIMILAR ON 43-34975 AT ROLL-OUT BOTH AIRCRAFT CARRIED INSIGNIA SERIAL NLII7BER NUMEROUS STENCILLED NOTICES ON FUSELAGE ID N 42 Model Aviation AERO PROQUCTS PROPELLER BLADE 3 MATT BLACK BLADE YELLOW TIP ROOT SCCT1ON NACA 65 2-017 STAT/Oil 06D1M412 0 0 51277 7551512 p251408 252664 503764 754586 105264 iS6330 207130 255 7705 50 8125 358381 408495 456434 50 0152 55 7629 60 6903 65 6000 70 4986 75 3976 80*2936 85 1909 90 1043 95 361 1000 X-X Y rip SECTION NACA 67-CI3j15 UPPER SURFACE LOWER SURFACE STATION ORDINATE STATION RDiNAT 0000 422 1209378 1129 663 1450837 1340 1151-8451351675 2392547261-2245 4883504515 -2996 737424 7763 3559 9-87485510134013 148858401319-4736 198965970115281 249072082510-5722 299276733000-6051 346480225506-6296 399682634004-6463 449883934502-654 9 500084265000-6566 5302834254986490 6005812559956351 650877526492-6046 701171886909-5620 751462817487-4927 8012506179883 965 850936668491-2850 900622078965-1677 95028649498 614 10001000 II SIGHT 3 2------ ROOT SEC77ON OHCo 15 66CH0R0 NACA 652-017 030-EzII7~7IIjTIP SECTION s3J 22 CHORD HACA 67I-1315 COCKPIT VENTILATION X SECTIONS ON COOLING GILLS Co 2 WiNG-TIP piror oi 4334916 CoJ F ELEVATOR TRIM TAB CONTROL SORN Co 3 PITOT 6 F6JRING 01 4334915 o3 p AILERON TAB o3 RUDDER TAB o3 6-8F-9 MAX WiDTH OP 17LLET TTFf 5FT6F17F-8 ENLARGED DETAILS CoL5 l5o GIVEN SCALE o22o Co33o PITOT TUBE MACHINE GUN 6 CAMERA PORTS WERE NOT INSTALLED ON 43-34915 IIN AWEL J SCAI.E BELL AIRCRAFT CORP TR14 D-6 3349I5 COOLING GILLS SIMILAR ON RIGHT SIDE SEE DETAIL REAR LETT COWL PANEL SIMILAR ON 43-34916 J4p 1982 U SAAF BELL XP77 MODEL AVIATION July 198243 little wooden Bell novel ideas turned hardware heat World War II Like others took long nft rd fighters day just faded away bled academic way Curtiss P-36 Air Corps already having built course C460 doesnt look bit like Curtiss P-36 military version would have about same size power performance So much brainstorm basic idea lightweight fighter didnt die fact several months before debut Caudron Los Angeles Bell Aircraft Co begun design work novel lightweight pursuit plane would have its engine middle its propeller driven long extension shaft What become P-39 Aircobra ordered Air Corps 1937 first flew early 1939 P-39 weighed under 4000 lb empty qualifying lightweight though hardly small Caudron Racer As often case Airacobra grew production prototype weighed over 4500 lb first YP-39 up 5000 lb time first airplanes delivered Air Corps squadrons P-39Ds empty weight up almost 5500 lb Hack drawing ~d.. few months after P-39 entered service early 1941 Gen Arnold back 400-hp 4000 lb 400 mph idea design work began Bell what first called Tri-4 light highly maneuver able interceptor According final report project Tri-4 airplane proposed Bell have high speed 410 mph 27000 feet 500-hp equipped supercharged Ranger XV-770-9 engine Its design gross weight about 3700 lb carry 22mm cannon firing through propeller hub addition two 50-caliber synchronized nose guns airfoil laminar flow type May 16 1942 initial batch 25 air planes ordered Two weeks later Bell sug gested building six airplanes shortage engines total cost including profit set just under $500000 first airplane delivered within six months sixth January 1943 Tri-4 work out promised Bell perhaps lightweight fighter would reality things rarely go smoothly June 1942 Air Corps decided airplane should built wood conserve scarce alumi num much came areas being oc cupied Japanese Bell realized Continued page 132 44 Model Aviation truly BIG PuTS S-2A want superb 135 scale biplane kit features easy-to-build Snap-Lock construction numbered die-cut hand-machined balsa hardwood parts vacuum-formed cowl wheel pants clear windscreen neces sary hardware color decals full-size plans photo building guide radio installation directions List Price$32995 E&R Price$21995 BELLANCA DECATHLON top quality kit Pilot has wingspan 96/3 1519 sq area 60 long Kit features numbered die-cut hand-machined parts pre-cut window 3-dimensional instrument panel fullsized plans photo building guide pre-formed cowl wheel pants plus much List Price$30495 E&R Price$22995 NEW Bellanca Decathlon 40 same /4-scale kit above smaller has wingspan 67/4 774 sq wing area designed fly 40- 60-size engine List Price$13995 E&R Price$10695 FUTABA 6-FP-6FN radio complete standard charger including ERR special heavy-duty /4-scale pack age includes 4 large servos produce 154 oz torque 1 standard S-26 servo use throttle control also include heavy-duty 1800 MAH battery pack List Price$46990 E&R Price$32999 R R 1 Box 10 ______ Edgeley ND 58433 701/493-2015~obbieS PRODUCTS Complete Line Exhaust Systems * Tuned Pipes * Muffled Tuned Pipes * Headers * Venturi Mufflers * Expansion Mufflers Helicopter Ball Mufflers ialized Exhaust Systems Unsurpassed Worh~ h Pqrformance Nate 5 7208 7224 7240 7564 MHz Nate 6 See sec 2106 Commissions Rules Nate 7 NG49 following frequencies may autharized low-power 1 watt input mobile operations radio services shown subject condition no inter ference caused reception television stations operating channels 4 5 Manufacturers Radio Service MHZMHzMHzMHZMHZ 7202 7210 7218 7226 7234 7204 7212 7220 7228 7236 7206 7214 7222 7230 7238 7208 7216 7224 7232 7240 Special Industrial Radio Service Manufacturers Radio Service Railroad Radio Service MHz MHz MHz MHZ MHZ 7244 7252 7260 7548 7556 724d 7256 7544 7552 7560 Nate 8 NG56 Th frequencies 7208 7216 7224 7232 7240 7296 7564 MHz may authorized low power 1-watt put mobile operations Personal Radio Services radio control models subject condition interference will caused remote control industrial equip ment operating same adjacent fre quencies reception television stations operating Channels 4 5 TV terference shall considered occur ever reception regularly used television signals Impaired destroyed regardless strength television signais distance television station Note 9 No doubt reason Academy has requested access band segment 7586-7600 MHZ Bell XP-77/Berliner Continued paoe 44 tough would switch materials probably would have quit spot late June design gross weight up pqfl performance ysrem TOP PERFORMANCE K&B ENGINES 16 Airplane 4 Marine K&B FUELSK&B GLOW PLUGS 7 Blends4 choices Matched Finish System BEST APPEARANCE K&B FIBERGLASS CLOTH K&B Micro-Balloons FILLER K&B SUPER POXY RESIN KAB SUPER POSY THINNER K&B SUPER POSY PRIMER K&9 SUPER FOXY PAINT K&B MIXING CUPS 3650 lb still within plans Arnolds formula high wing loading would mean such long takeoff run decided cut structure gross weight 3000 lb Already price tag up $700000 end sight January 1943 six airplanes supposed have delivered Bell told Air Corps serious complications arisen efforts build high-speed airplane wood aiming July delivery first airplanes others end year schedule almost year off cost project up S2 million Bell blamed slippage need sub contract wood construction companies werent already loaded work troopcarrying gliders major friction tween Bell its subcontractors matters quality inspection working drawings top off Ranger engine having cooling troubles May 1943 serious thought given dumping entire XP-77 project because Bell couldnt concentrate- enough effort company too busy its P-63 Kingcobra very secret P-59 Airacomet jet flown first time October 1942 Finally Air Corps decided cancel thing first two prototypes felt would useful obtainingvaluable flight data type plywood aircraft troubles came light Bell stopped inspecting production factory Goshen Indiana Veneer Co building wings Air Corps help Bell discovered Goshen built set test wings no flight wings November 1943 Vidal Research Corp built both 132 Model Aviation scale Pitts S2A Pilot Kit Scale Flight u-uzu GEARED PROP DRIVE Swing Big Prop Realistic RPM Its she2 Ooncs Piop $1950 eKII-107 Con Pee Wee 020o 020 ,II sog 7-4 0-4 prOp 4 roabstcJeibcerrt sc4e IligOl KRESS TECHNOLOGY INC 27 Mdi Road IEI 6 11PM Lloyd i-lan,, N V 11743 00 /Ditibot inqokie ore lenited ZONA SAWS The one wood handle good blade Razor #200 $210 Sabre * 400 -$185 Sa100-389 Replacement blades available yosr dealer ModeS SupplyPO Box 3957 A 90510 uSA Super Mini Boy Recommended Eigines Radios- Mufflers Helicopter tools stock Worlds stable easiest fly small 40 size R/O Helicopter Low maintenance mechanics engineer ed Dieter Schiuter Father RIO Helicopters Features fully collective Bell mixing main rotor head upright spinner starting straight shaft driven tail rotor & automatic compensation symmet rical prebuilt main rotor tail rotor blades autorotation clutch Uses standard 4 chanel radio Kits parts stock guarantee helicopters fly Ask man flies Move up Schiuter inSifrp U SEAN IflG subsidiary MINIATURE AIRCRAFT 2594 North Orange Blossom Trail ndo FL 32804 Phone 30514224531 test fuselages six flight fuselages high-altitude version Ranger V- 12 seriously delayed XP-77 use low-altitude engine its performance would inferior fighter airplane comparison existing models now production ac cording USAAF Technical Report #5359 Vidal Research took over job building wings made schedule slip Problems arose over matters basic time needed spread glue Completion first airplane delayed February 1944 Marcfr would make almost 1 years late wasnt until April Fools Day 1944 XP-77 flew Bells Niagra Falls NY factory Success last Far proto type arrived Wright Field May 2 soon revealed serious vibration 1700 rpm 2300 rpm probably due lack shock absorbers engine mounts June 6 1944 Allied troops storming Nor mandy beaches final assault Nazi-held Europe USAAF got around giving prototype XP-77 its serial number 43-34915 Official flight tests carried out Eglin Field FL second XP-77 43-34916 starting late July 1944 October 2 airplane fell out Immelmann turn inverted spin pilot recovered air plane went upright flat spin could recover forced jump pilot landed safely airplane demolished proved last straw project ended December 2 March 1945 war drawing close Army Air Forces completed report Flight Tests Bell XP-77 Airplane following has excerpted general handling characteristics XP-77 airplane satisfactory although restric tions evented dives spins violent maneuvers jectionable feature control system fixed trim tabs ailerons rudder results condition flight airplane will fly stick- rudder-free ground setting the. tabs Visibility good conditions flight ground handling Noise vibration cockpit considerable cockpit becomes very cold uncomfortable cold weather high altitude cockpit heat available high speed 328 mph obtained military power 3150 rpm 416 mani fold pressure 12600 ft critical altitude high speed 330 mph obtained war emergencypower 3300 rpm and57 at4000 ft critical altitude maximum rate climb obtained war emergency power 3630 feet per minute critical altitude 2000 ft ConclusionsThe overall performance XP-77 airplane inferior present fighter aircraft employed AAF results flight tests considerably lower estimated performance set Bell Aircraft Corp maximum speed airplane war emergency power considerably lower other AAF interceptor aircraft operating military power maximum rate climb military power very low interceptor air craft low service ceiling airplane renders useless against high altitude aircraft bad XP-77 fell 90 mph short its promised top speed rate climb no better 200-hp Pins Special aerobatic biplane service ceiling 30000 ft era P-38s would go 39000 ft P 51s would top 40000 ft interesting idea didnt work taught its creators lesson very very difficult build truly lightweight fighter plane General Dynamics learning lesson over again its F- 16 no longer lightweight Mach 2 ter course doesnt make sense give up such worthy goal As matter fact start Cassutt will close 250 mph 135-hp weighing little over 500 lb add couple machine guns some fuel radio two ours/Hill Continued page 80 other useful ingredients avoid building wing spar might dis solve its contents during flight samples balsa coated variety resins placed baby food jars containing candidate fuels array samples stored months backyard greenhouse exposure thermal cycling solvents brutal test Some combinations looked satisfactory dur ing winter turned messes July Sig Mfg Cos polyester finishing resin eventually chosen K&B finishing resin fared equally well test Scale modelers using chainsaw engines might find idea useful Its OK gasoline havent found resins will resist fuels containing nitromethane ether Engine modifications OS F560 engine received designed use glow plug ignition regular alcohol-based model fuel Gasoline far efficient alcohol glow plug ignition doesnt work well gasoline based fuels unless compression ratio increased point mechanical problems July 1982 133
Edition: Model Aviation - 1982/07
Page Numbers: 41, 42, 43, 44, 132, 133
400-HP 4000 LB 400 MPH General Hap Arnolds cute little formula lightweight fighter plane As top man US Army Air Forces World War II com manded lot attention Moreover idea very light simple fighter broad appeal time still does problem doesnt seem way Sure lot fighters start out light weights realities combat faced weight goes up size has go up handle weight Pretty soon clever little airplane has become just another big complicated machine classic example good idea can go sour Bell XP-77 have small empty weight under 3000 lb little engine 500-hp V-12 simple design drawback didnt work Its performance far below what Bell Aircraft promised Furthermore took twice long bring flying status did first American jet built same time Bell terrific idea sure fact XP 77 inspired exciting air planes ever seen French Caudron C460 Michel Detroyat dominated 1936 Los Angeles National Air Races Any airplane sleek efficient Caudron its background should have winner theres big dif ference between racing planes combat planes September 1936 US Army Air Corps Gen Henry Hap Arnold sent test pilots Ben Kelsey Los Angeles take look sensational Caudron see would possible create fighter like Kelsey now deceased spent last days historian National Air Space Museum did told highly impressed little French racer broken Thompson Trophy Race speed record despite having half cubic inches previous record holder As racer all-time greats see might turned military airplane First would need larger wheels tires could operate grass runways would mean thicker heavier wing retract landing gear would cut speed Next would have carry lot fuel plus few machine guns armor plating understandably absent racer Suddenly racer weighed 1300 lb empty would well over 2000 lb growing happens wing area would have increased lift extra weight beefing up structure would necessary would have horsepower pull would bring weight would mean wing area etc etc Caudrons superb streamlining would have get same treatment Its canopy desned speed order give fighter pilot chance see might shooting him canopy would have raised lot glass added drag weight would come guns aerials bomb shackles added Maintenance another problem wasnt quite obvious racer no access holes inspection minor repairs lot would have installed along weight parts moved around make easier work under wartime conditions Ben Kelsey got back Wright Field reported Arnold Caudron modified make fighter its numbers dimensions weight power came out very interesting way modified racer resem July 198241 GRA TEFUL THANKS TO DON BERLINER FOR RESEARCI-FING DETAILED INFORMATION INCLUDED HERE ATHERINEII E CASSITY OF THE AIR FORCE MUSEUM WHO SUPPLIED ADDITIONAL MA TERIAL Ar EXTREMELY SHORT NOTICE C I1671 AIRFOIL SECTIONS AT ROOT TIP 6F NACA LOW- DRAG WING VALUES ARE PERCENTAGES OF CHO ROOT SECTION ONLY IS SYMMETRICAL * REAR LIGHT UE VIEW ON TORQUE LINKS 0 BOTH AIRCRAFT WERE ALUMINUM OVERALL WITH SERIALS ETC BLACK COLOURS OF FUSELAGE S RUDDER STRIPING TO 43-34975 NOT KNOWN DETAILS LANDING GEAR RETRACTING MECHANISM NOT KNOWN DATA WINGSPAN WING AREA10011 ASPECT RATIOZ5 OVERALL LENGTH 22-A STABILIZER SPAN -WHEEL TRACK C PROPELLER DIA --- 9-d EMPTY WEIGHT-- 2855 DESIGN lb 43-349 GROSS WEIGHT 3583 lb 43-3 \ 43-34976 SECTIONS C OIL COOLER VENT ING GILLS ING GILLS SNOWN OPEN 975 & 9167 INTERNAL DETAILS APE APPROXIMATE JRUE V7EW ON TORQUE LINKS 3J MODIFICATIONS TO COVER DOORS INCLUDE SECOND JOINT TO HINGED UPPER PANEL REMOVAL OF NARROW BOTTOM SEGMENT 54 LEFT MAIN LEG FULLY EXTENDED NO LOAD AULIC LINE OMITTEDKIT NOTE VARIATION IN TAILCONE PROFILES 6 TORQUE LINKS OMITTED 3 NOSE WHEEL LEG FULLY EXTENDEO NO LOAD ANOPY ROTATES AFT IN SIDE FUSELAGE COCKPIT DETAILS NOT KNOWN 43-3491IE COOLING GILLS SIMILAR ON LEFT SIDESEE DETAIL OIL COOLER EXIT DUCT SIMILAR ON 43-34975 AT ROLL-OUT BOTH AIRCRAFT CARRIED INSIGNIA SERIAL NLII7BER NUMEROUS STENCILLED NOTICES ON FUSELAGE ID N 42 Model Aviation AERO PROQUCTS PROPELLER BLADE 3 MATT BLACK BLADE YELLOW TIP ROOT SCCT1ON NACA 65 2-017 STAT/Oil 06D1M412 0 0 51277 7551512 p251408 252664 503764 754586 105264 iS6330 207130 255 7705 50 8125 358381 408495 456434 50 0152 55 7629 60 6903 65 6000 70 4986 75 3976 80*2936 85 1909 90 1043 95 361 1000 X-X Y rip SECTION NACA 67-CI3j15 UPPER SURFACE LOWER SURFACE STATION ORDINATE STATION RDiNAT 0000 422 1209378 1129 663 1450837 1340 1151-8451351675 2392547261-2245 4883504515 -2996 737424 7763 3559 9-87485510134013 148858401319-4736 198965970115281 249072082510-5722 299276733000-6051 346480225506-6296 399682634004-6463 449883934502-654 9 500084265000-6566 5302834254986490 6005812559956351 650877526492-6046 701171886909-5620 751462817487-4927 8012506179883 965 850936668491-2850 900622078965-1677 95028649498 614 10001000 II SIGHT 3 2------ ROOT SEC77ON OHCo 15 66CH0R0 NACA 652-017 030-EzII7~7IIjTIP SECTION s3J 22 CHORD HACA 67I-1315 COCKPIT VENTILATION X SECTIONS ON COOLING GILLS Co 2 WiNG-TIP piror oi 4334916 CoJ F ELEVATOR TRIM TAB CONTROL SORN Co 3 PITOT 6 F6JRING 01 4334915 o3 p AILERON TAB o3 RUDDER TAB o3 6-8F-9 MAX WiDTH OP 17LLET TTFf 5FT6F17F-8 ENLARGED DETAILS CoL5 l5o GIVEN SCALE o22o Co33o PITOT TUBE MACHINE GUN 6 CAMERA PORTS WERE NOT INSTALLED ON 43-34915 IIN AWEL J SCAI.E BELL AIRCRAFT CORP TR14 D-6 3349I5 COOLING GILLS SIMILAR ON RIGHT SIDE SEE DETAIL REAR LETT COWL PANEL SIMILAR ON 43-34916 J4p 1982 U SAAF BELL XP77 MODEL AVIATION July 198243 little wooden Bell novel ideas turned hardware heat World War II Like others took long nft rd fighters day just faded away bled academic way Curtiss P-36 Air Corps already having built course C460 doesnt look bit like Curtiss P-36 military version would have about same size power performance So much brainstorm basic idea lightweight fighter didnt die fact several months before debut Caudron Los Angeles Bell Aircraft Co begun design work novel lightweight pursuit plane would have its engine middle its propeller driven long extension shaft What become P-39 Aircobra ordered Air Corps 1937 first flew early 1939 P-39 weighed under 4000 lb empty qualifying lightweight though hardly small Caudron Racer As often case Airacobra grew production prototype weighed over 4500 lb first YP-39 up 5000 lb time first airplanes delivered Air Corps squadrons P-39Ds empty weight up almost 5500 lb Hack drawing ~d.. few months after P-39 entered service early 1941 Gen Arnold back 400-hp 4000 lb 400 mph idea design work began Bell what first called Tri-4 light highly maneuver able interceptor According final report project Tri-4 airplane proposed Bell have high speed 410 mph 27000 feet 500-hp equipped supercharged Ranger XV-770-9 engine Its design gross weight about 3700 lb carry 22mm cannon firing through propeller hub addition two 50-caliber synchronized nose guns airfoil laminar flow type May 16 1942 initial batch 25 air planes ordered Two weeks later Bell sug gested building six airplanes shortage engines total cost including profit set just under $500000 first airplane delivered within six months sixth January 1943 Tri-4 work out promised Bell perhaps lightweight fighter would reality things rarely go smoothly June 1942 Air Corps decided airplane should built wood conserve scarce alumi num much came areas being oc cupied Japanese Bell realized Continued page 132 44 Model Aviation truly BIG PuTS S-2A want superb 135 scale biplane kit features easy-to-build Snap-Lock construction numbered die-cut hand-machined balsa hardwood parts vacuum-formed cowl wheel pants clear windscreen neces sary hardware color decals full-size plans photo building guide radio installation directions List Price$32995 E&R Price$21995 BELLANCA DECATHLON top quality kit Pilot has wingspan 96/3 1519 sq area 60 long Kit features numbered die-cut hand-machined parts pre-cut window 3-dimensional instrument panel fullsized plans photo building guide pre-formed cowl wheel pants plus much List Price$30495 E&R Price$22995 NEW Bellanca Decathlon 40 same /4-scale kit above smaller has wingspan 67/4 774 sq wing area designed fly 40- 60-size engine List Price$13995 E&R Price$10695 FUTABA 6-FP-6FN radio complete standard charger including ERR special heavy-duty /4-scale pack age includes 4 large servos produce 154 oz torque 1 standard S-26 servo use throttle control also include heavy-duty 1800 MAH battery pack List Price$46990 E&R Price$32999 R R 1 Box 10 ______ Edgeley ND 58433 701/493-2015~obbieS PRODUCTS Complete Line Exhaust Systems * Tuned Pipes * Muffled Tuned Pipes * Headers * Venturi Mufflers * Expansion Mufflers Helicopter Ball Mufflers ialized Exhaust Systems Unsurpassed Worh~ h Pqrformance Nate 5 7208 7224 7240 7564 MHz Nate 6 See sec 2106 Commissions Rules Nate 7 NG49 following frequencies may autharized low-power 1 watt input mobile operations radio services shown subject condition no inter ference caused reception television stations operating channels 4 5 Manufacturers Radio Service MHZMHzMHzMHZMHZ 7202 7210 7218 7226 7234 7204 7212 7220 7228 7236 7206 7214 7222 7230 7238 7208 7216 7224 7232 7240 Special Industrial Radio Service Manufacturers Radio Service Railroad Radio Service MHz MHz MHz MHZ MHZ 7244 7252 7260 7548 7556 724d 7256 7544 7552 7560 Nate 8 NG56 Th frequencies 7208 7216 7224 7232 7240 7296 7564 MHz may authorized low power 1-watt put mobile operations Personal Radio Services radio control models subject condition interference will caused remote control industrial equip ment operating same adjacent fre quencies reception television stations operating Channels 4 5 TV terference shall considered occur ever reception regularly used television signals Impaired destroyed regardless strength television signais distance television station Note 9 No doubt reason Academy has requested access band segment 7586-7600 MHZ Bell XP-77/Berliner Continued paoe 44 tough would switch materials probably would have quit spot late June design gross weight up pqfl performance ysrem TOP PERFORMANCE K&B ENGINES 16 Airplane 4 Marine K&B FUELSK&B GLOW PLUGS 7 Blends4 choices Matched Finish System BEST APPEARANCE K&B FIBERGLASS CLOTH K&B Micro-Balloons FILLER K&B SUPER POXY RESIN KAB SUPER POSY THINNER K&B SUPER POSY PRIMER K&9 SUPER FOXY PAINT K&B MIXING CUPS 3650 lb still within plans Arnolds formula high wing loading would mean such long takeoff run decided cut structure gross weight 3000 lb Already price tag up $700000 end sight January 1943 six airplanes supposed have delivered Bell told Air Corps serious complications arisen efforts build high-speed airplane wood aiming July delivery first airplanes others end year schedule almost year off cost project up S2 million Bell blamed slippage need sub contract wood construction companies werent already loaded work troopcarrying gliders major friction tween Bell its subcontractors matters quality inspection working drawings top off Ranger engine having cooling troubles May 1943 serious thought given dumping entire XP-77 project because Bell couldnt concentrate- enough effort company too busy its P-63 Kingcobra very secret P-59 Airacomet jet flown first time October 1942 Finally Air Corps decided cancel thing first two prototypes felt would useful obtainingvaluable flight data type plywood aircraft troubles came light Bell stopped inspecting production factory Goshen Indiana Veneer Co building wings Air Corps help Bell discovered Goshen built set test wings no flight wings November 1943 Vidal Research Corp built both 132 Model Aviation scale Pitts S2A Pilot Kit Scale Flight u-uzu GEARED PROP DRIVE Swing Big Prop Realistic RPM Its she2 Ooncs Piop $1950 eKII-107 Con Pee Wee 020o 020 ,II sog 7-4 0-4 prOp 4 roabstcJeibcerrt sc4e IligOl KRESS TECHNOLOGY INC 27 Mdi Road IEI 6 11PM Lloyd i-lan,, N V 11743 00 /Ditibot inqokie ore lenited ZONA SAWS The one wood handle good blade Razor #200 $210 Sabre * 400 -$185 Sa100-389 Replacement blades available yosr dealer ModeS SupplyPO Box 3957 A 90510 uSA Super Mini Boy Recommended Eigines Radios- Mufflers Helicopter tools stock Worlds stable easiest fly small 40 size R/O Helicopter Low maintenance mechanics engineer ed Dieter Schiuter Father RIO Helicopters Features fully collective Bell mixing main rotor head upright spinner starting straight shaft driven tail rotor & automatic compensation symmet rical prebuilt main rotor tail rotor blades autorotation clutch Uses standard 4 chanel radio Kits parts stock guarantee helicopters fly Ask man flies Move up Schiuter inSifrp U SEAN IflG subsidiary MINIATURE AIRCRAFT 2594 North Orange Blossom Trail ndo FL 32804 Phone 30514224531 test fuselages six flight fuselages high-altitude version Ranger V- 12 seriously delayed XP-77 use low-altitude engine its performance would inferior fighter airplane comparison existing models now production ac cording USAAF Technical Report #5359 Vidal Research took over job building wings made schedule slip Problems arose over matters basic time needed spread glue Completion first airplane delayed February 1944 Marcfr would make almost 1 years late wasnt until April Fools Day 1944 XP-77 flew Bells Niagra Falls NY factory Success last Far proto type arrived Wright Field May 2 soon revealed serious vibration 1700 rpm 2300 rpm probably due lack shock absorbers engine mounts June 6 1944 Allied troops storming Nor mandy beaches final assault Nazi-held Europe USAAF got around giving prototype XP-77 its serial number 43-34915 Official flight tests carried out Eglin Field FL second XP-77 43-34916 starting late July 1944 October 2 airplane fell out Immelmann turn inverted spin pilot recovered air plane went upright flat spin could recover forced jump pilot landed safely airplane demolished proved last straw project ended December 2 March 1945 war drawing close Army Air Forces completed report Flight Tests Bell XP-77 Airplane following has excerpted general handling characteristics XP-77 airplane satisfactory although restric tions evented dives spins violent maneuvers jectionable feature control system fixed trim tabs ailerons rudder results condition flight airplane will fly stick- rudder-free ground setting the. tabs Visibility good conditions flight ground handling Noise vibration cockpit considerable cockpit becomes very cold uncomfortable cold weather high altitude cockpit heat available high speed 328 mph obtained military power 3150 rpm 416 mani fold pressure 12600 ft critical altitude high speed 330 mph obtained war emergencypower 3300 rpm and57 at4000 ft critical altitude maximum rate climb obtained war emergency power 3630 feet per minute critical altitude 2000 ft ConclusionsThe overall performance XP-77 airplane inferior present fighter aircraft employed AAF results flight tests considerably lower estimated performance set Bell Aircraft Corp maximum speed airplane war emergency power considerably lower other AAF interceptor aircraft operating military power maximum rate climb military power very low interceptor air craft low service ceiling airplane renders useless against high altitude aircraft bad XP-77 fell 90 mph short its promised top speed rate climb no better 200-hp Pins Special aerobatic biplane service ceiling 30000 ft era P-38s would go 39000 ft P 51s would top 40000 ft interesting idea didnt work taught its creators lesson very very difficult build truly lightweight fighter plane General Dynamics learning lesson over again its F- 16 no longer lightweight Mach 2 ter course doesnt make sense give up such worthy goal As matter fact start Cassutt will close 250 mph 135-hp weighing little over 500 lb add couple machine guns some fuel radio two ours/Hill Continued page 80 other useful ingredients avoid building wing spar might dis solve its contents during flight samples balsa coated variety resins placed baby food jars containing candidate fuels array samples stored months backyard greenhouse exposure thermal cycling solvents brutal test Some combinations looked satisfactory dur ing winter turned messes July Sig Mfg Cos polyester finishing resin eventually chosen K&B finishing resin fared equally well test Scale modelers using chainsaw engines might find idea useful Its OK gasoline havent found resins will resist fuels containing nitromethane ether Engine modifications OS F560 engine received designed use glow plug ignition regular alcohol-based model fuel Gasoline far efficient alcohol glow plug ignition doesnt work well gasoline based fuels unless compression ratio increased point mechanical problems July 1982 133
Edition: Model Aviation - 1982/07
Page Numbers: 41, 42, 43, 44, 132, 133
400-HP 4000 LB 400 MPH General Hap Arnolds cute little formula lightweight fighter plane As top man US Army Air Forces World War II com manded lot attention Moreover idea very light simple fighter broad appeal time still does problem doesnt seem way Sure lot fighters start out light weights realities combat faced weight goes up size has go up handle weight Pretty soon clever little airplane has become just another big complicated machine classic example good idea can go sour Bell XP-77 have small empty weight under 3000 lb little engine 500-hp V-12 simple design drawback didnt work Its performance far below what Bell Aircraft promised Furthermore took twice long bring flying status did first American jet built same time Bell terrific idea sure fact XP 77 inspired exciting air planes ever seen French Caudron C460 Michel Detroyat dominated 1936 Los Angeles National Air Races Any airplane sleek efficient Caudron its background should have winner theres big dif ference between racing planes combat planes September 1936 US Army Air Corps Gen Henry Hap Arnold sent test pilots Ben Kelsey Los Angeles take look sensational Caudron see would possible create fighter like Kelsey now deceased spent last days historian National Air Space Museum did told highly impressed little French racer broken Thompson Trophy Race speed record despite having half cubic inches previous record holder As racer all-time greats see might turned military airplane First would need larger wheels tires could operate grass runways would mean thicker heavier wing retract landing gear would cut speed Next would have carry lot fuel plus few machine guns armor plating understandably absent racer Suddenly racer weighed 1300 lb empty would well over 2000 lb growing happens wing area would have increased lift extra weight beefing up structure would necessary would have horsepower pull would bring weight would mean wing area etc etc Caudrons superb streamlining would have get same treatment Its canopy desned speed order give fighter pilot chance see might shooting him canopy would have raised lot glass added drag weight would come guns aerials bomb shackles added Maintenance another problem wasnt quite obvious racer no access holes inspection minor repairs lot would have installed along weight parts moved around make easier work under wartime conditions Ben Kelsey got back Wright Field reported Arnold Caudron modified make fighter its numbers dimensions weight power came out very interesting way modified racer resem July 198241 GRA TEFUL THANKS TO DON BERLINER FOR RESEARCI-FING DETAILED INFORMATION INCLUDED HERE ATHERINEII E CASSITY OF THE AIR FORCE MUSEUM WHO SUPPLIED ADDITIONAL MA TERIAL Ar EXTREMELY SHORT NOTICE C I1671 AIRFOIL SECTIONS AT ROOT TIP 6F NACA LOW- DRAG WING VALUES ARE PERCENTAGES OF CHO ROOT SECTION ONLY IS SYMMETRICAL * REAR LIGHT UE VIEW ON TORQUE LINKS 0 BOTH AIRCRAFT WERE ALUMINUM OVERALL WITH SERIALS ETC BLACK COLOURS OF FUSELAGE S RUDDER STRIPING TO 43-34975 NOT KNOWN DETAILS LANDING GEAR RETRACTING MECHANISM NOT KNOWN DATA WINGSPAN WING AREA10011 ASPECT RATIOZ5 OVERALL LENGTH 22-A STABILIZER SPAN -WHEEL TRACK C PROPELLER DIA --- 9-d EMPTY WEIGHT-- 2855 DESIGN lb 43-349 GROSS WEIGHT 3583 lb 43-3 \ 43-34976 SECTIONS C OIL COOLER VENT ING GILLS ING GILLS SNOWN OPEN 975 & 9167 INTERNAL DETAILS APE APPROXIMATE JRUE V7EW ON TORQUE LINKS 3J MODIFICATIONS TO COVER DOORS INCLUDE SECOND JOINT TO HINGED UPPER PANEL REMOVAL OF NARROW BOTTOM SEGMENT 54 LEFT MAIN LEG FULLY EXTENDED NO LOAD AULIC LINE OMITTEDKIT NOTE VARIATION IN TAILCONE PROFILES 6 TORQUE LINKS OMITTED 3 NOSE WHEEL LEG FULLY EXTENDEO NO LOAD ANOPY ROTATES AFT IN SIDE FUSELAGE COCKPIT DETAILS NOT KNOWN 43-3491IE COOLING GILLS SIMILAR ON LEFT SIDESEE DETAIL OIL COOLER EXIT DUCT SIMILAR ON 43-34975 AT ROLL-OUT BOTH AIRCRAFT CARRIED INSIGNIA SERIAL NLII7BER NUMEROUS STENCILLED NOTICES ON FUSELAGE ID N 42 Model Aviation AERO PROQUCTS PROPELLER BLADE 3 MATT BLACK BLADE YELLOW TIP ROOT SCCT1ON NACA 65 2-017 STAT/Oil 06D1M412 0 0 51277 7551512 p251408 252664 503764 754586 105264 iS6330 207130 255 7705 50 8125 358381 408495 456434 50 0152 55 7629 60 6903 65 6000 70 4986 75 3976 80*2936 85 1909 90 1043 95 361 1000 X-X Y rip SECTION NACA 67-CI3j15 UPPER SURFACE LOWER SURFACE STATION ORDINATE STATION RDiNAT 0000 422 1209378 1129 663 1450837 1340 1151-8451351675 2392547261-2245 4883504515 -2996 737424 7763 3559 9-87485510134013 148858401319-4736 198965970115281 249072082510-5722 299276733000-6051 346480225506-6296 399682634004-6463 449883934502-654 9 500084265000-6566 5302834254986490 6005812559956351 650877526492-6046 701171886909-5620 751462817487-4927 8012506179883 965 850936668491-2850 900622078965-1677 95028649498 614 10001000 II SIGHT 3 2------ ROOT SEC77ON OHCo 15 66CH0R0 NACA 652-017 030-EzII7~7IIjTIP SECTION s3J 22 CHORD HACA 67I-1315 COCKPIT VENTILATION X SECTIONS ON COOLING GILLS Co 2 WiNG-TIP piror oi 4334916 CoJ F ELEVATOR TRIM TAB CONTROL SORN Co 3 PITOT 6 F6JRING 01 4334915 o3 p AILERON TAB o3 RUDDER TAB o3 6-8F-9 MAX WiDTH OP 17LLET TTFf 5FT6F17F-8 ENLARGED DETAILS CoL5 l5o GIVEN SCALE o22o Co33o PITOT TUBE MACHINE GUN 6 CAMERA PORTS WERE NOT INSTALLED ON 43-34915 IIN AWEL J SCAI.E BELL AIRCRAFT CORP TR14 D-6 3349I5 COOLING GILLS SIMILAR ON RIGHT SIDE SEE DETAIL REAR LETT COWL PANEL SIMILAR ON 43-34916 J4p 1982 U SAAF BELL XP77 MODEL AVIATION July 198243 little wooden Bell novel ideas turned hardware heat World War II Like others took long nft rd fighters day just faded away bled academic way Curtiss P-36 Air Corps already having built course C460 doesnt look bit like Curtiss P-36 military version would have about same size power performance So much brainstorm basic idea lightweight fighter didnt die fact several months before debut Caudron Los Angeles Bell Aircraft Co begun design work novel lightweight pursuit plane would have its engine middle its propeller driven long extension shaft What become P-39 Aircobra ordered Air Corps 1937 first flew early 1939 P-39 weighed under 4000 lb empty qualifying lightweight though hardly small Caudron Racer As often case Airacobra grew production prototype weighed over 4500 lb first YP-39 up 5000 lb time first airplanes delivered Air Corps squadrons P-39Ds empty weight up almost 5500 lb Hack drawing ~d.. few months after P-39 entered service early 1941 Gen Arnold back 400-hp 4000 lb 400 mph idea design work began Bell what first called Tri-4 light highly maneuver able interceptor According final report project Tri-4 airplane proposed Bell have high speed 410 mph 27000 feet 500-hp equipped supercharged Ranger XV-770-9 engine Its design gross weight about 3700 lb carry 22mm cannon firing through propeller hub addition two 50-caliber synchronized nose guns airfoil laminar flow type May 16 1942 initial batch 25 air planes ordered Two weeks later Bell sug gested building six airplanes shortage engines total cost including profit set just under $500000 first airplane delivered within six months sixth January 1943 Tri-4 work out promised Bell perhaps lightweight fighter would reality things rarely go smoothly June 1942 Air Corps decided airplane should built wood conserve scarce alumi num much came areas being oc cupied Japanese Bell realized Continued page 132 44 Model Aviation truly BIG PuTS S-2A want superb 135 scale biplane kit features easy-to-build Snap-Lock construction numbered die-cut hand-machined balsa hardwood parts vacuum-formed cowl wheel pants clear windscreen neces sary hardware color decals full-size plans photo building guide radio installation directions List Price$32995 E&R Price$21995 BELLANCA DECATHLON top quality kit Pilot has wingspan 96/3 1519 sq area 60 long Kit features numbered die-cut hand-machined parts pre-cut window 3-dimensional instrument panel fullsized plans photo building guide pre-formed cowl wheel pants plus much List Price$30495 E&R Price$22995 NEW Bellanca Decathlon 40 same /4-scale kit above smaller has wingspan 67/4 774 sq wing area designed fly 40- 60-size engine List Price$13995 E&R Price$10695 FUTABA 6-FP-6FN radio complete standard charger including ERR special heavy-duty /4-scale pack age includes 4 large servos produce 154 oz torque 1 standard S-26 servo use throttle control also include heavy-duty 1800 MAH battery pack List Price$46990 E&R Price$32999 R R 1 Box 10 ______ Edgeley ND 58433 701/493-2015~obbieS PRODUCTS Complete Line Exhaust Systems * Tuned Pipes * Muffled Tuned Pipes * Headers * Venturi Mufflers * Expansion Mufflers Helicopter Ball Mufflers ialized Exhaust Systems Unsurpassed Worh~ h Pqrformance Nate 5 7208 7224 7240 7564 MHz Nate 6 See sec 2106 Commissions Rules Nate 7 NG49 following frequencies may autharized low-power 1 watt input mobile operations radio services shown subject condition no inter ference caused reception television stations operating channels 4 5 Manufacturers Radio Service MHZMHzMHzMHZMHZ 7202 7210 7218 7226 7234 7204 7212 7220 7228 7236 7206 7214 7222 7230 7238 7208 7216 7224 7232 7240 Special Industrial Radio Service Manufacturers Radio Service Railroad Radio Service MHz MHz MHz MHZ MHZ 7244 7252 7260 7548 7556 724d 7256 7544 7552 7560 Nate 8 NG56 Th frequencies 7208 7216 7224 7232 7240 7296 7564 MHz may authorized low power 1-watt put mobile operations Personal Radio Services radio control models subject condition interference will caused remote control industrial equip ment operating same adjacent fre quencies reception television stations operating Channels 4 5 TV terference shall considered occur ever reception regularly used television signals Impaired destroyed regardless strength television signais distance television station Note 9 No doubt reason Academy has requested access band segment 7586-7600 MHZ Bell XP-77/Berliner Continued paoe 44 tough would switch materials probably would have quit spot late June design gross weight up pqfl performance ysrem TOP PERFORMANCE K&B ENGINES 16 Airplane 4 Marine K&B FUELSK&B GLOW PLUGS 7 Blends4 choices Matched Finish System BEST APPEARANCE K&B FIBERGLASS CLOTH K&B Micro-Balloons FILLER K&B SUPER POXY RESIN KAB SUPER POSY THINNER K&B SUPER POSY PRIMER K&9 SUPER FOXY PAINT K&B MIXING CUPS 3650 lb still within plans Arnolds formula high wing loading would mean such long takeoff run decided cut structure gross weight 3000 lb Already price tag up $700000 end sight January 1943 six airplanes supposed have delivered Bell told Air Corps serious complications arisen efforts build high-speed airplane wood aiming July delivery first airplanes others end year schedule almost year off cost project up S2 million Bell blamed slippage need sub contract wood construction companies werent already loaded work troopcarrying gliders major friction tween Bell its subcontractors matters quality inspection working drawings top off Ranger engine having cooling troubles May 1943 serious thought given dumping entire XP-77 project because Bell couldnt concentrate- enough effort company too busy its P-63 Kingcobra very secret P-59 Airacomet jet flown first time October 1942 Finally Air Corps decided cancel thing first two prototypes felt would useful obtainingvaluable flight data type plywood aircraft troubles came light Bell stopped inspecting production factory Goshen Indiana Veneer Co building wings Air Corps help Bell discovered Goshen built set test wings no flight wings November 1943 Vidal Research Corp built both 132 Model Aviation scale Pitts S2A Pilot Kit Scale Flight u-uzu GEARED PROP DRIVE Swing Big Prop Realistic RPM Its she2 Ooncs Piop $1950 eKII-107 Con Pee Wee 020o 020 ,II sog 7-4 0-4 prOp 4 roabstcJeibcerrt sc4e IligOl KRESS TECHNOLOGY INC 27 Mdi Road IEI 6 11PM Lloyd i-lan,, N V 11743 00 /Ditibot inqokie ore lenited ZONA SAWS The one wood handle good blade Razor #200 $210 Sabre * 400 -$185 Sa100-389 Replacement blades available yosr dealer ModeS SupplyPO Box 3957 A 90510 uSA Super Mini Boy Recommended Eigines Radios- Mufflers Helicopter tools stock Worlds stable easiest fly small 40 size R/O Helicopter Low maintenance mechanics engineer ed Dieter Schiuter Father RIO Helicopters Features fully collective Bell mixing main rotor head upright spinner starting straight shaft driven tail rotor & automatic compensation symmet rical prebuilt main rotor tail rotor blades autorotation clutch Uses standard 4 chanel radio Kits parts stock guarantee helicopters fly Ask man flies Move up Schiuter inSifrp U SEAN IflG subsidiary MINIATURE AIRCRAFT 2594 North Orange Blossom Trail ndo FL 32804 Phone 30514224531 test fuselages six flight fuselages high-altitude version Ranger V- 12 seriously delayed XP-77 use low-altitude engine its performance would inferior fighter airplane comparison existing models now production ac cording USAAF Technical Report #5359 Vidal Research took over job building wings made schedule slip Problems arose over matters basic time needed spread glue Completion first airplane delayed February 1944 Marcfr would make almost 1 years late wasnt until April Fools Day 1944 XP-77 flew Bells Niagra Falls NY factory Success last Far proto type arrived Wright Field May 2 soon revealed serious vibration 1700 rpm 2300 rpm probably due lack shock absorbers engine mounts June 6 1944 Allied troops storming Nor mandy beaches final assault Nazi-held Europe USAAF got around giving prototype XP-77 its serial number 43-34915 Official flight tests carried out Eglin Field FL second XP-77 43-34916 starting late July 1944 October 2 airplane fell out Immelmann turn inverted spin pilot recovered air plane went upright flat spin could recover forced jump pilot landed safely airplane demolished proved last straw project ended December 2 March 1945 war drawing close Army Air Forces completed report Flight Tests Bell XP-77 Airplane following has excerpted general handling characteristics XP-77 airplane satisfactory although restric tions evented dives spins violent maneuvers jectionable feature control system fixed trim tabs ailerons rudder results condition flight airplane will fly stick- rudder-free ground setting the. tabs Visibility good conditions flight ground handling Noise vibration cockpit considerable cockpit becomes very cold uncomfortable cold weather high altitude cockpit heat available high speed 328 mph obtained military power 3150 rpm 416 mani fold pressure 12600 ft critical altitude high speed 330 mph obtained war emergencypower 3300 rpm and57 at4000 ft critical altitude maximum rate climb obtained war emergency power 3630 feet per minute critical altitude 2000 ft ConclusionsThe overall performance XP-77 airplane inferior present fighter aircraft employed AAF results flight tests considerably lower estimated performance set Bell Aircraft Corp maximum speed airplane war emergency power considerably lower other AAF interceptor aircraft operating military power maximum rate climb military power very low interceptor air craft low service ceiling airplane renders useless against high altitude aircraft bad XP-77 fell 90 mph short its promised top speed rate climb no better 200-hp Pins Special aerobatic biplane service ceiling 30000 ft era P-38s would go 39000 ft P 51s would top 40000 ft interesting idea didnt work taught its creators lesson very very difficult build truly lightweight fighter plane General Dynamics learning lesson over again its F- 16 no longer lightweight Mach 2 ter course doesnt make sense give up such worthy goal As matter fact start Cassutt will close 250 mph 135-hp weighing little over 500 lb add couple machine guns some fuel radio two ours/Hill Continued page 80 other useful ingredients avoid building wing spar might dis solve its contents during flight samples balsa coated variety resins placed baby food jars containing candidate fuels array samples stored months backyard greenhouse exposure thermal cycling solvents brutal test Some combinations looked satisfactory dur ing winter turned messes July Sig Mfg Cos polyester finishing resin eventually chosen K&B finishing resin fared equally well test Scale modelers using chainsaw engines might find idea useful Its OK gasoline havent found resins will resist fuels containing nitromethane ether Engine modifications OS F560 engine received designed use glow plug ignition regular alcohol-based model fuel Gasoline far efficient alcohol glow plug ignition doesnt work well gasoline based fuels unless compression ratio increased point mechanical problems July 1982 133
Edition: Model Aviation - 1982/07
Page Numbers: 41, 42, 43, 44, 132, 133
400-HP 4000 LB 400 MPH General Hap Arnolds cute little formula lightweight fighter plane As top man US Army Air Forces World War II com manded lot attention Moreover idea very light simple fighter broad appeal time still does problem doesnt seem way Sure lot fighters start out light weights realities combat faced weight goes up size has go up handle weight Pretty soon clever little airplane has become just another big complicated machine classic example good idea can go sour Bell XP-77 have small empty weight under 3000 lb little engine 500-hp V-12 simple design drawback didnt work Its performance far below what Bell Aircraft promised Furthermore took twice long bring flying status did first American jet built same time Bell terrific idea sure fact XP 77 inspired exciting air planes ever seen French Caudron C460 Michel Detroyat dominated 1936 Los Angeles National Air Races Any airplane sleek efficient Caudron its background should have winner theres big dif ference between racing planes combat planes September 1936 US Army Air Corps Gen Henry Hap Arnold sent test pilots Ben Kelsey Los Angeles take look sensational Caudron see would possible create fighter like Kelsey now deceased spent last days historian National Air Space Museum did told highly impressed little French racer broken Thompson Trophy Race speed record despite having half cubic inches previous record holder As racer all-time greats see might turned military airplane First would need larger wheels tires could operate grass runways would mean thicker heavier wing retract landing gear would cut speed Next would have carry lot fuel plus few machine guns armor plating understandably absent racer Suddenly racer weighed 1300 lb empty would well over 2000 lb growing happens wing area would have increased lift extra weight beefing up structure would necessary would have horsepower pull would bring weight would mean wing area etc etc Caudrons superb streamlining would have get same treatment Its canopy desned speed order give fighter pilot chance see might shooting him canopy would have raised lot glass added drag weight would come guns aerials bomb shackles added Maintenance another problem wasnt quite obvious racer no access holes inspection minor repairs lot would have installed along weight parts moved around make easier work under wartime conditions Ben Kelsey got back Wright Field reported Arnold Caudron modified make fighter its numbers dimensions weight power came out very interesting way modified racer resem July 198241 GRA TEFUL THANKS TO DON BERLINER FOR RESEARCI-FING DETAILED INFORMATION INCLUDED HERE ATHERINEII E CASSITY OF THE AIR FORCE MUSEUM WHO SUPPLIED ADDITIONAL MA TERIAL Ar EXTREMELY SHORT NOTICE C I1671 AIRFOIL SECTIONS AT ROOT TIP 6F NACA LOW- DRAG WING VALUES ARE PERCENTAGES OF CHO ROOT SECTION ONLY IS SYMMETRICAL * REAR LIGHT UE VIEW ON TORQUE LINKS 0 BOTH AIRCRAFT WERE ALUMINUM OVERALL WITH SERIALS ETC BLACK COLOURS OF FUSELAGE S RUDDER STRIPING TO 43-34975 NOT KNOWN DETAILS LANDING GEAR RETRACTING MECHANISM NOT KNOWN DATA WINGSPAN WING AREA10011 ASPECT RATIOZ5 OVERALL LENGTH 22-A STABILIZER SPAN -WHEEL TRACK C PROPELLER DIA --- 9-d EMPTY WEIGHT-- 2855 DESIGN lb 43-349 GROSS WEIGHT 3583 lb 43-3 \ 43-34976 SECTIONS C OIL COOLER VENT ING GILLS ING GILLS SNOWN OPEN 975 & 9167 INTERNAL DETAILS APE APPROXIMATE JRUE V7EW ON TORQUE LINKS 3J MODIFICATIONS TO COVER DOORS INCLUDE SECOND JOINT TO HINGED UPPER PANEL REMOVAL OF NARROW BOTTOM SEGMENT 54 LEFT MAIN LEG FULLY EXTENDED NO LOAD AULIC LINE OMITTEDKIT NOTE VARIATION IN TAILCONE PROFILES 6 TORQUE LINKS OMITTED 3 NOSE WHEEL LEG FULLY EXTENDEO NO LOAD ANOPY ROTATES AFT IN SIDE FUSELAGE COCKPIT DETAILS NOT KNOWN 43-3491IE COOLING GILLS SIMILAR ON LEFT SIDESEE DETAIL OIL COOLER EXIT DUCT SIMILAR ON 43-34975 AT ROLL-OUT BOTH AIRCRAFT CARRIED INSIGNIA SERIAL NLII7BER NUMEROUS STENCILLED NOTICES ON FUSELAGE ID N 42 Model Aviation AERO PROQUCTS PROPELLER BLADE 3 MATT BLACK BLADE YELLOW TIP ROOT SCCT1ON NACA 65 2-017 STAT/Oil 06D1M412 0 0 51277 7551512 p251408 252664 503764 754586 105264 iS6330 207130 255 7705 50 8125 358381 408495 456434 50 0152 55 7629 60 6903 65 6000 70 4986 75 3976 80*2936 85 1909 90 1043 95 361 1000 X-X Y rip SECTION NACA 67-CI3j15 UPPER SURFACE LOWER SURFACE STATION ORDINATE STATION RDiNAT 0000 422 1209378 1129 663 1450837 1340 1151-8451351675 2392547261-2245 4883504515 -2996 737424 7763 3559 9-87485510134013 148858401319-4736 198965970115281 249072082510-5722 299276733000-6051 346480225506-6296 399682634004-6463 449883934502-654 9 500084265000-6566 5302834254986490 6005812559956351 650877526492-6046 701171886909-5620 751462817487-4927 8012506179883 965 850936668491-2850 900622078965-1677 95028649498 614 10001000 II SIGHT 3 2------ ROOT SEC77ON OHCo 15 66CH0R0 NACA 652-017 030-EzII7~7IIjTIP SECTION s3J 22 CHORD HACA 67I-1315 COCKPIT VENTILATION X SECTIONS ON COOLING GILLS Co 2 WiNG-TIP piror oi 4334916 CoJ F ELEVATOR TRIM TAB CONTROL SORN Co 3 PITOT 6 F6JRING 01 4334915 o3 p AILERON TAB o3 RUDDER TAB o3 6-8F-9 MAX WiDTH OP 17LLET TTFf 5FT6F17F-8 ENLARGED DETAILS CoL5 l5o GIVEN SCALE o22o Co33o PITOT TUBE MACHINE GUN 6 CAMERA PORTS WERE NOT INSTALLED ON 43-34915 IIN AWEL J SCAI.E BELL AIRCRAFT CORP TR14 D-6 3349I5 COOLING GILLS SIMILAR ON RIGHT SIDE SEE DETAIL REAR LETT COWL PANEL SIMILAR ON 43-34916 J4p 1982 U SAAF BELL XP77 MODEL AVIATION July 198243 little wooden Bell novel ideas turned hardware heat World War II Like others took long nft rd fighters day just faded away bled academic way Curtiss P-36 Air Corps already having built course C460 doesnt look bit like Curtiss P-36 military version would have about same size power performance So much brainstorm basic idea lightweight fighter didnt die fact several months before debut Caudron Los Angeles Bell Aircraft Co begun design work novel lightweight pursuit plane would have its engine middle its propeller driven long extension shaft What become P-39 Aircobra ordered Air Corps 1937 first flew early 1939 P-39 weighed under 4000 lb empty qualifying lightweight though hardly small Caudron Racer As often case Airacobra grew production prototype weighed over 4500 lb first YP-39 up 5000 lb time first airplanes delivered Air Corps squadrons P-39Ds empty weight up almost 5500 lb Hack drawing ~d.. few months after P-39 entered service early 1941 Gen Arnold back 400-hp 4000 lb 400 mph idea design work began Bell what first called Tri-4 light highly maneuver able interceptor According final report project Tri-4 airplane proposed Bell have high speed 410 mph 27000 feet 500-hp equipped supercharged Ranger XV-770-9 engine Its design gross weight about 3700 lb carry 22mm cannon firing through propeller hub addition two 50-caliber synchronized nose guns airfoil laminar flow type May 16 1942 initial batch 25 air planes ordered Two weeks later Bell sug gested building six airplanes shortage engines total cost including profit set just under $500000 first airplane delivered within six months sixth January 1943 Tri-4 work out promised Bell perhaps lightweight fighter would reality things rarely go smoothly June 1942 Air Corps decided airplane should built wood conserve scarce alumi num much came areas being oc cupied Japanese Bell realized Continued page 132 44 Model Aviation truly BIG PuTS S-2A want superb 135 scale biplane kit features easy-to-build Snap-Lock construction numbered die-cut hand-machined balsa hardwood parts vacuum-formed cowl wheel pants clear windscreen neces sary hardware color decals full-size plans photo building guide radio installation directions List Price$32995 E&R Price$21995 BELLANCA DECATHLON top quality kit Pilot has wingspan 96/3 1519 sq area 60 long Kit features numbered die-cut hand-machined parts pre-cut window 3-dimensional instrument panel fullsized plans photo building guide pre-formed cowl wheel pants plus much List Price$30495 E&R Price$22995 NEW Bellanca Decathlon 40 same /4-scale kit above smaller has wingspan 67/4 774 sq wing area designed fly 40- 60-size engine List Price$13995 E&R Price$10695 FUTABA 6-FP-6FN radio complete standard charger including ERR special heavy-duty /4-scale pack age includes 4 large servos produce 154 oz torque 1 standard S-26 servo use throttle control also include heavy-duty 1800 MAH battery pack List Price$46990 E&R Price$32999 R R 1 Box 10 ______ Edgeley ND 58433 701/493-2015~obbieS PRODUCTS Complete Line Exhaust Systems * Tuned Pipes * Muffled Tuned Pipes * Headers * Venturi Mufflers * Expansion Mufflers Helicopter Ball Mufflers ialized Exhaust Systems Unsurpassed Worh~ h Pqrformance Nate 5 7208 7224 7240 7564 MHz Nate 6 See sec 2106 Commissions Rules Nate 7 NG49 following frequencies may autharized low-power 1 watt input mobile operations radio services shown subject condition no inter ference caused reception television stations operating channels 4 5 Manufacturers Radio Service MHZMHzMHzMHZMHZ 7202 7210 7218 7226 7234 7204 7212 7220 7228 7236 7206 7214 7222 7230 7238 7208 7216 7224 7232 7240 Special Industrial Radio Service Manufacturers Radio Service Railroad Radio Service MHz MHz MHz MHZ MHZ 7244 7252 7260 7548 7556 724d 7256 7544 7552 7560 Nate 8 NG56 Th frequencies 7208 7216 7224 7232 7240 7296 7564 MHz may authorized low power 1-watt put mobile operations Personal Radio Services radio control models subject condition interference will caused remote control industrial equip ment operating same adjacent fre quencies reception television stations operating Channels 4 5 TV terference shall considered occur ever reception regularly used television signals Impaired destroyed regardless strength television signais distance television station Note 9 No doubt reason Academy has requested access band segment 7586-7600 MHZ Bell XP-77/Berliner Continued paoe 44 tough would switch materials probably would have quit spot late June design gross weight up pqfl performance ysrem TOP PERFORMANCE K&B ENGINES 16 Airplane 4 Marine K&B FUELSK&B GLOW PLUGS 7 Blends4 choices Matched Finish System BEST APPEARANCE K&B FIBERGLASS CLOTH K&B Micro-Balloons FILLER K&B SUPER POXY RESIN KAB SUPER POSY THINNER K&B SUPER POSY PRIMER K&9 SUPER FOXY PAINT K&B MIXING CUPS 3650 lb still within plans Arnolds formula high wing loading would mean such long takeoff run decided cut structure gross weight 3000 lb Already price tag up $700000 end sight January 1943 six airplanes supposed have delivered Bell told Air Corps serious complications arisen efforts build high-speed airplane wood aiming July delivery first airplanes others end year schedule almost year off cost project up S2 million Bell blamed slippage need sub contract wood construction companies werent already loaded work troopcarrying gliders major friction tween Bell its subcontractors matters quality inspection working drawings top off Ranger engine having cooling troubles May 1943 serious thought given dumping entire XP-77 project because Bell couldnt concentrate- enough effort company too busy its P-63 Kingcobra very secret P-59 Airacomet jet flown first time October 1942 Finally Air Corps decided cancel thing first two prototypes felt would useful obtainingvaluable flight data type plywood aircraft troubles came light Bell stopped inspecting production factory Goshen Indiana Veneer Co building wings Air Corps help Bell discovered Goshen built set test wings no flight wings November 1943 Vidal Research Corp built both 132 Model Aviation scale Pitts S2A Pilot Kit Scale Flight u-uzu GEARED PROP DRIVE Swing Big Prop Realistic RPM Its she2 Ooncs Piop $1950 eKII-107 Con Pee Wee 020o 020 ,II sog 7-4 0-4 prOp 4 roabstcJeibcerrt sc4e IligOl KRESS TECHNOLOGY INC 27 Mdi Road IEI 6 11PM Lloyd i-lan,, N V 11743 00 /Ditibot inqokie ore lenited ZONA SAWS The one wood handle good blade Razor #200 $210 Sabre * 400 -$185 Sa100-389 Replacement blades available yosr dealer ModeS SupplyPO Box 3957 A 90510 uSA Super Mini Boy Recommended Eigines Radios- Mufflers Helicopter tools stock Worlds stable easiest fly small 40 size R/O Helicopter Low maintenance mechanics engineer ed Dieter Schiuter Father RIO Helicopters Features fully collective Bell mixing main rotor head upright spinner starting straight shaft driven tail rotor & automatic compensation symmet rical prebuilt main rotor tail rotor blades autorotation clutch Uses standard 4 chanel radio Kits parts stock guarantee helicopters fly Ask man flies Move up Schiuter inSifrp U SEAN IflG subsidiary MINIATURE AIRCRAFT 2594 North Orange Blossom Trail ndo FL 32804 Phone 30514224531 test fuselages six flight fuselages high-altitude version Ranger V- 12 seriously delayed XP-77 use low-altitude engine its performance would inferior fighter airplane comparison existing models now production ac cording USAAF Technical Report #5359 Vidal Research took over job building wings made schedule slip Problems arose over matters basic time needed spread glue Completion first airplane delayed February 1944 Marcfr would make almost 1 years late wasnt until April Fools Day 1944 XP-77 flew Bells Niagra Falls NY factory Success last Far proto type arrived Wright Field May 2 soon revealed serious vibration 1700 rpm 2300 rpm probably due lack shock absorbers engine mounts June 6 1944 Allied troops storming Nor mandy beaches final assault Nazi-held Europe USAAF got around giving prototype XP-77 its serial number 43-34915 Official flight tests carried out Eglin Field FL second XP-77 43-34916 starting late July 1944 October 2 airplane fell out Immelmann turn inverted spin pilot recovered air plane went upright flat spin could recover forced jump pilot landed safely airplane demolished proved last straw project ended December 2 March 1945 war drawing close Army Air Forces completed report Flight Tests Bell XP-77 Airplane following has excerpted general handling characteristics XP-77 airplane satisfactory although restric tions evented dives spins violent maneuvers jectionable feature control system fixed trim tabs ailerons rudder results condition flight airplane will fly stick- rudder-free ground setting the. tabs Visibility good conditions flight ground handling Noise vibration cockpit considerable cockpit becomes very cold uncomfortable cold weather high altitude cockpit heat available high speed 328 mph obtained military power 3150 rpm 416 mani fold pressure 12600 ft critical altitude high speed 330 mph obtained war emergencypower 3300 rpm and57 at4000 ft critical altitude maximum rate climb obtained war emergency power 3630 feet per minute critical altitude 2000 ft ConclusionsThe overall performance XP-77 airplane inferior present fighter aircraft employed AAF results flight tests considerably lower estimated performance set Bell Aircraft Corp maximum speed airplane war emergency power considerably lower other AAF interceptor aircraft operating military power maximum rate climb military power very low interceptor air craft low service ceiling airplane renders useless against high altitude aircraft bad XP-77 fell 90 mph short its promised top speed rate climb no better 200-hp Pins Special aerobatic biplane service ceiling 30000 ft era P-38s would go 39000 ft P 51s would top 40000 ft interesting idea didnt work taught its creators lesson very very difficult build truly lightweight fighter plane General Dynamics learning lesson over again its F- 16 no longer lightweight Mach 2 ter course doesnt make sense give up such worthy goal As matter fact start Cassutt will close 250 mph 135-hp weighing little over 500 lb add couple machine guns some fuel radio two ours/Hill Continued page 80 other useful ingredients avoid building wing spar might dis solve its contents during flight samples balsa coated variety resins placed baby food jars containing candidate fuels array samples stored months backyard greenhouse exposure thermal cycling solvents brutal test Some combinations looked satisfactory dur ing winter turned messes July Sig Mfg Cos polyester finishing resin eventually chosen K&B finishing resin fared equally well test Scale modelers using chainsaw engines might find idea useful Its OK gasoline havent found resins will resist fuels containing nitromethane ether Engine modifications OS F560 engine received designed use glow plug ignition regular alcohol-based model fuel Gasoline far efficient alcohol glow plug ignition doesnt work well gasoline based fuels unless compression ratio increased point mechanical problems July 1982 133