FREE FLIGHT INDOOR KIBBIE DOME REPORT Much following information taken report hy Leo Mary Smothers including photos discussed below spite colder-than-usual temperatures kept times down everyone good time Contestants Dallas Jim Clem St Louis Larry Coslick others over West Coast showed up three days intense flying contest format resembles used NIMAS Annual Record Trials flown West Baden mid-1970s format fly event events interest mostall three days suits emphasis informal flying ngid contest schedule Wally Miller originated Easy B developing new event intended help bridge gap between Easy B FlD models Wally calls event PRO-20 set up limits monoplane 68 square inches projected area 50% max stab maximum projected wingspan 20 inches Wallys model first break 20 minutes Andy Tagliafico logged best time 2628 Design goal 30 minutes Some top times events Intermediate Stick Wally Miller 2445 FiD two flight total Steve Brown 8304 Manhattan Cabin Larry Coslick 1057 Easy B Larry Coslick 2238 Pennyplane John Lenderman 1211 Limited Pennyplane John Lenderman 1101 Ornithopter Warren Williams 743 ROG Larry Coslick 1057 MiniStick Andy Tagliafico 1044 Federated ROG Andy Tagliafico 810 Perhaps best yardstick conditions times often closely parallel winning times USIC very similar site years best USIC Pennyplane time 1611 Bernie Wisniewski John Lendermans 1211 same event Kibbie significantly lower Tan II new crop Tan rubber out Figure 1 BA o Four critical torque values living room flying Climb C bounce B C Text has details year has much lighter color previous hatches new tan has nickname Fran Clem said looks like fettucini Fettucini oops Tan II has different characteristics Tan stretches takes turns apparently has higher energy storage high end torque curve much steeper earlier Tan steeper high end torque slope Pirelli Although Tan II still takes lot getting used number better fliers year did very well using Larry Coslick notes Tan II seems less tolerant low temperatures Tan also feels similar times turns available using shorter loops larger cross-sections changes made similar performance motor Tan used 16-inch 1oop 044 width compared 14-inch loop 048 Tan II quick calculation indicates new motor about four percent lighter would fair try compare energy storage specific energy energy/unit weight basis numbers Some testers report five ten percent higher specific energy storage capabilities over best batches Tan Given higher energy steeper torque slope would reasonable expect Tan II have better utility lower ceilings due longer mid-torque slope Figure 2 Pitchpi x 2 x L x jr/wi Carved prop block helical pitch distribution Angular difference between two stations remains same Tan II model can use extreme torque burst efficiently launching absolute max torque should enable high-ceiling performance good also Good Idea year Indoor contests held Oregon accompanied seminars after flying sessions Noted fliers give excellent programs variety topics fliers area arent very well known other areas always well come contests other areas year speakers included Lew Gitlow Andy Tagliafico Ed B array Hying opportunities listings below have new information available CDs please fill dates after March 1993 Continued page 119 Figure 3 Pitch distributionhelical plus five degrees Diameter 246610121416 II II Pitch distribution 20 helical pitch Pitch distributionhelical minus five degrees Pitch distribution comparison blades 20-mci pitch helical prop blades twisted fbi degrees higher five degrees lower angle 110 Model Aviation Allisons Skylark SRX-1 Flying Aces Club FAC Jumbo Scale model cruises slowly past camera Larry Coslick winding Manhattan Cabin model Kibbie Dome First place 1057 Mary Smothers photo John Lenderman tweaks winning Limited Pennnyplane model Kibbie Winning time 1101 5 Join theGiantsHelp Promote INon-CompetitiveI HIG inffII s.c, Flying Large RIC Air Cra ft I IMAA membership includes quarterly magazine High Flight I MEMBERSHIP APPUCAllON IJ NEW fJ RENEWAL Date19I Yearly Dues$1500 USA $2000 US Canada & Mexico $3000 US ElsewhereI Make CHECK MONEY ORDER Payable INTERNAllONAL MINIAlURE AIRCRAFT ASSOCIATION INC I Name _________________ Phone ___________ Street _________________________________________ P0 Box/Route Box __________________ II 1City State/Province ________________Zip _________________ 1IMAA AMA Number ___________MAAC _________Chapter L TO IMAA Secretary DONE VINEYARD 205k Hiliciale Road a KS 67401 FF Indoor/Tenny Continued page 110 later Refer October 1993 column list site contact persons BE SAFE Check contest status before leaving home CaliforniaBurbank area Blacksheep Exhibition Squadron have Cat Indoor meets Luther Burbank Middle School second Friday month 7 pm-l0 pm Tony Naccarato 2121 N Hollywood Way Burbank CA 91507 Tel 818 842-5062 CaliforniaLos Angeles area Possible sessions 60-foot Downtown LA Armory Stadium Way Contact Otto Kuhni Tel 213 872-0882 CaliforniaMann County 20 miles north San Francisco Year-round minicontests 8 am-2 pm fourth Sunday month site standard basketball court 28 feet clear Contact Tom Brennan 21326 Via Colombard Sonoma CA 95476 Tel 707 938-2893 CaliforniaSan Diego Fun Fly Scale sessions second Friday month monthly sessions fourth Friday Colina Del Sol Community Center Cat 5316 Orange Ave San Diego Howard Haupt 3860 Ecochee Ave San Diego CA 92117 Tel 619 272-5656 ConnecticutGlastonbury Flying sessions Glastonbury High School Gym George Armstead 89 Harvest Lane Glastonbury CT 06037 Tel 203 633-7836 FloridaMeets sponsored Miami Indoor Airplane Modelers Association Contact John Martin 2180 Tigertail Ave Miami FL 33133 Tel 305 858-6363 Continued page 151 Cressline Models Inc QUIcKIE $10995 VIGGEN $33995 1441 N Mayfair Road aukee WI 53226 257-1923 Fax 414 771-2092 7iI7 MCI VISA AF-5E AGGRESSOR tq*O O * AMERIcAS FAVORITE $15495 * 1/8 Scale 70 LX 1/5 Scale 626 WS 4-5 Channel 40 Eng Channel 34 OZAC Sport Scale Canard ~jjadjeai7a TIGERSIIARK $339 95* 1/8 Scale 70 Lx 48 annel 33 oz Wing Load 712 aq area $329 95* 1/16 Scale 67 x 64 WS 4-9 Channel 28 oz Wing Load 832 aq area PRICES SUBJECT 70 CHANGEPIus Shipping & HandlIng January1994 119 2 order call Eric Sanders 299-7684 5 pm-iO pm EST Monday-Friday day Sat Sun 1W t IC flS 511111 CAD airfoil editor-move coordinatee w/mouae create new points round out leading edgee undo mode 64x zoom pan mode coordinate 0 mode ahowa current cursor position etc use windowing interface Pop up text editor document airfoil changes-saved coordinates ulates elliptical planform rib lengtha Chord queue allows templates several chord lengths printed out unattended edit coordinates Pop-up calculator conversions s foam outline screen optimize template height Customizable screen colors are airfoils screen printer using overlay mode ts mirror image Calculates panel volume & surface area aide weight estimations Supports dot matrix laxer let printers Calculates projected panel area airfoil cross sectional area perimeter length tive negative washout Modity airfoils changing camber thicknessmirroring combining tops bottoms different airfoils Interpolates between different root tip airfoils position within wing panel uts DXF file Both scaled unscaled hi-ran screen preview modes her\Cut ItmI calculator much much morel. Remember wine accurate temolates CompuFoil Profeasional-$65 Airfoil Library w/135 airfoils-$1O S&H add $3 Also svailable-CompuFoil Standard-$25 CompuFoil Plus-$45 Demo Disk-$5 refundable order wilt compatability product ordering information 3904 Traine Dr. Kettering OH. 45429 09 2 J55 2 Fl III 1rxthlof/tsc/0ly 03 K FF Indoor/Tenny Continued page 119 IowaCedar Rapids Regular scheduled unsanctioned flying sessions Nov 93 through March 94 28-foot ceiling Paul Mcllrath 1524 48th St NE Cedar Rapids IA 52402 Tel 319 393-4677 KansasTopeka Topeka still looking site replace Stone Hangar Check periodically Jack Koeblar 3425 SW Arrowhead Rd Topeka KS 66614-3485 Tel 913 272-8439 see what find. KansasWichita Session Friends University 28-foot site 12-6 pm Planned first weekend month subject approval Jan 94 through March 94 Normal schedule heavy events 12-2 pm lightweight events 2 pm-6 pm Contact Stan Chilton 725 E Lincoln Wichita KS 67211-3302 Tel 316 686-9634 KentuckyLouisville Flying sessions Tuesday Sawyer Park site 11 am- 1 pm Also Saturday month subject military schedules Kentucky Air National Guard suite 10 am-2 pm Contact Mason Plank 3207 Oriole Dr Louisville KY 40213 Tel 502 634-8191 New YorkBrooklyn Indoor contests March April 1994 Blue Nose Hangar Floyd Bennett Field Brooklyn Site has 150- x 450-foot floor 45 feet rafters field truss beam easy retrieval Contact Don Ross 38 Churchill Rd Cresskill NJ 07626 Tel 201 568-5272 PennsylvaniaPhiladelphia Flying Byrn Athen Fairmont Park Joe Krush 409 Warner Rd Wayne PA 19087 Tel 215 688-3027 OklahomaOklahoma City Sessions contests planned third weekend month Jan 94-March 94 Jim Belson 4933 NW 29th Oklahoma City OK 73129 Tel 405 946-1093 OklahomaTulsa Sessions/contests planned second weekend month Jan 14 Feb 12 March 12 Roy OMara 9120 7th St Tulsa OK 74112 Tel 918 835-6880 MiniStick Hints Living room trim During final days International MiniStick Postal Jim Clem checked out recreation room house hoped make up having regular flying session during duration postal meet room 19 feet square peaked ceiling about 14 feet high ceiling specification called height measurement made five-meter circle checked out 10 feet inch times Jims best flight 417 turned 344 Normally models fly about same realized too late subtle difference trim between two models model still trimmed 26-foot Bedford site did 700 December Jims model trimmed slightly nose-up normal Bedford trim difference showed ceiling contacts model built up too much speed between contacts third contact usually worked its way corner Jims model did classic stall-and-turn tightened circle enough get near peak Once stopped climbing usually centered four feet higher same stage flight power factor Both models shared same flight strategyflying entirely flat part torque curve shown Figure 1 represents typical torque curve critical values marked critical values represent approximate ideal Launch torque initially chosen climb rate minimize rate climb length ceiling contact B Torque first ceiling contact C Level-flight torque end climbing D Touchdown torque model climbs torque drops C bounces during torque range B C proper trim ceiling lots luck torque will reach point C model centered well enough land floor final factor consider choosing rubber 1oop length cross-section hold number turns expended between torque levels D model landing too turns shorten loop lighten model effectively lengthen first part curve about flat ceiling really smooth flat ceiling can potentially give higher duration room large enough major difference two ceiling types model can fly slightly faster long can ceiling-scrub getting too far off-center Otherwise must fly slowlyenough hesitate ceiling contact made Additional washin left wingtip should cause tip stall model turns tightly Some models widen turn contact flat ceiling bottom line high livingroom times require extensive flight testing special adjustments precise rubber selection higher ceilings Most likely best rubber cross-section will larger feasible use higher ceilings shortest possible 1oop will give required number turns over range torque used CyA Comments following abstracted article SAM 86 Speaks original material credited Woodcuts magazine Should Modelers Worry About Molecule Growth Some glues fail because curing process causes molecules grow large interconnecting bonds reduced number until material easily fractures particular certain cyanoacrylares virtually turn powder Some rapidly curing cyanoacrylates continue cure until molecules become large no longer weld other cohesion two surfaces intended held together adhesion better-known cyanoacrylates formulated limit such molecular growth Among best 3M Hot Stuff lines As general rule slower-curing cyanoacrylates form much smaller molecules An extra minute curing time can contribute substantially long-term strength Indoor Props prop almost important part Indoor model half important part prop/rubber combination Any Indoor model competitive weight reasonable trim will well long airframe stiff enough hold adjustments point prop rubber combination makes difference Basic prop theory begins definition pitch formula Pitch blade element 6 x tan angle x diameter Can illustrated solving pitch angle vs diameter Pitch nches DiameterBlade Angle 2726 4 579 6 467 8385 10 325 12 279 14 16 Angle 450 DiameterPitch 2628 4126 6188 8251 10314 12377 24414440 21716503 300 Pitch 363 725 109 145 181 218 254 290 charts highlight difference between standard true-pitch helicalpitch prop constant-angle prop constant-angle props computed table have flat non-twisted blades mounted either 30 45 degrees obvious thing note about constant angle prop blade tips would very much pulling helical-pitch prop computed above could built carved block like Figure 2 key fact remember January1994 151 FF Indoor/Tenny Continued page 151 about prop blades built form angular difference between two blade stations remain same blade rotated shortened discussed below Modifying Existing Props us have constructed props using tissue socket hub allows us change prop blades rotate blades different angle matched sets different diameter possible tailor old props new models Simply rotating blades new angle makes minor adjustments existing prop Lets examine what happens 20inch-pitch prop computed above Assume have cut inch out center prop spars leave 15 inches diameter Using tissue sockets can splice two blades together following chart compares blade angle vs diameter data previously shown pitch resulting four kinds change prop blade can rotated lower angle higher angle can shortened also can shortened rotated higher angle computations show results rotating blade five degrees five degrees less shortening 16-inch diameter 15 inches blade one-halfinch shorter right column combines effect shortening blade increasing angle five degrees case computation begins angle blade element shown original chart computed result same segment shown change condition right CL AerobaticslMcMillan Continued page 123 Tech Tips Last year discussed sealing control surface hinge lines extremely effective trimming tool Because chances good will help no question should try new planes Although doesnt help planes wont know until give go benefit prevention funnies Windy Urtnowski calls outboard wing rebuilt Caudron popped up top inside outside rounds First sealed CL Speed/Lee Continued paqe 125 needle setting wont change Different pins required different props stored hole end block kept threaded brass plug terrific accessory ease prop modification increase flight repeatability Another interesting thing Nats Bill Wisniewskis 21 K&B engine used grandson Mike 21 Sport Speed Bill used sleeve piston Sportster 20 drum rotor space between hinges wing still behaved same desperation ran continuous strip root tip funny gone best could figure out hinge cutouts tip bleeding air small things can real killers main reason brought up pass information found unlikely place using 3Ms plastic tape satisfactory adhesive effective because low tack however since tape bit thick controls somewhat stiff led search something better Continued page 165 rear end used marine version engine built ball-bearing crankshaft crankcase trouble conrodthe bronze bushing kept going outso pressed high-silicon aluminum bushing worked great engine ran very well K&B engines now have clearance conrods much 005 being used lower end engine performance reliability better ever See Nats photos couple new engines Wiley 40 Jett 40 Ill try get performance information future column h itch after change DiaBlade Angle 2 726 4 579 6 467 8 385 10 325 12 279 14 244 16 217 152 166 168 166 163 159 155 150 266 246 239 238 241 244 248 253 15 dia 149 175 183 187 190 191 192 214 215 219 224 229 234 239 Figure 3 graphs pitch distribution rotated blades comparison standard 20-inch helical blade using variable pitch props think about widely pitch varies over range allow angle change may profit planning what pitch block build blades use high-pitch block equal upper limit setting lower settings will have center blade doing work efficient Im sure anyone knows sure interesting think about Model Aviation 4
Edition: Model Aviation - 1994/01
Page Numbers: 110, 119, 151, 152
FREE FLIGHT INDOOR KIBBIE DOME REPORT Much following information taken report hy Leo Mary Smothers including photos discussed below spite colder-than-usual temperatures kept times down everyone good time Contestants Dallas Jim Clem St Louis Larry Coslick others over West Coast showed up three days intense flying contest format resembles used NIMAS Annual Record Trials flown West Baden mid-1970s format fly event events interest mostall three days suits emphasis informal flying ngid contest schedule Wally Miller originated Easy B developing new event intended help bridge gap between Easy B FlD models Wally calls event PRO-20 set up limits monoplane 68 square inches projected area 50% max stab maximum projected wingspan 20 inches Wallys model first break 20 minutes Andy Tagliafico logged best time 2628 Design goal 30 minutes Some top times events Intermediate Stick Wally Miller 2445 FiD two flight total Steve Brown 8304 Manhattan Cabin Larry Coslick 1057 Easy B Larry Coslick 2238 Pennyplane John Lenderman 1211 Limited Pennyplane John Lenderman 1101 Ornithopter Warren Williams 743 ROG Larry Coslick 1057 MiniStick Andy Tagliafico 1044 Federated ROG Andy Tagliafico 810 Perhaps best yardstick conditions times often closely parallel winning times USIC very similar site years best USIC Pennyplane time 1611 Bernie Wisniewski John Lendermans 1211 same event Kibbie significantly lower Tan II new crop Tan rubber out Figure 1 BA o Four critical torque values living room flying Climb C bounce B C Text has details year has much lighter color previous hatches new tan has nickname Fran Clem said looks like fettucini Fettucini oops Tan II has different characteristics Tan stretches takes turns apparently has higher energy storage high end torque curve much steeper earlier Tan steeper high end torque slope Pirelli Although Tan II still takes lot getting used number better fliers year did very well using Larry Coslick notes Tan II seems less tolerant low temperatures Tan also feels similar times turns available using shorter loops larger cross-sections changes made similar performance motor Tan used 16-inch 1oop 044 width compared 14-inch loop 048 Tan II quick calculation indicates new motor about four percent lighter would fair try compare energy storage specific energy energy/unit weight basis numbers Some testers report five ten percent higher specific energy storage capabilities over best batches Tan Given higher energy steeper torque slope would reasonable expect Tan II have better utility lower ceilings due longer mid-torque slope Figure 2 Pitchpi x 2 x L x jr/wi Carved prop block helical pitch distribution Angular difference between two stations remains same Tan II model can use extreme torque burst efficiently launching absolute max torque should enable high-ceiling performance good also Good Idea year Indoor contests held Oregon accompanied seminars after flying sessions Noted fliers give excellent programs variety topics fliers area arent very well known other areas always well come contests other areas year speakers included Lew Gitlow Andy Tagliafico Ed B array Hying opportunities listings below have new information available CDs please fill dates after March 1993 Continued page 119 Figure 3 Pitch distributionhelical plus five degrees Diameter 246610121416 II II Pitch distribution 20 helical pitch Pitch distributionhelical minus five degrees Pitch distribution comparison blades 20-mci pitch helical prop blades twisted fbi degrees higher five degrees lower angle 110 Model Aviation Allisons Skylark SRX-1 Flying Aces Club FAC Jumbo Scale model cruises slowly past camera Larry Coslick winding Manhattan Cabin model Kibbie Dome First place 1057 Mary Smothers photo John Lenderman tweaks winning Limited Pennnyplane model Kibbie Winning time 1101 5 Join theGiantsHelp Promote INon-CompetitiveI HIG inffII s.c, Flying Large RIC Air Cra ft I IMAA membership includes quarterly magazine High Flight I MEMBERSHIP APPUCAllON IJ NEW fJ RENEWAL Date19I Yearly Dues$1500 USA $2000 US Canada & Mexico $3000 US ElsewhereI Make CHECK MONEY ORDER Payable INTERNAllONAL MINIAlURE AIRCRAFT ASSOCIATION INC I Name _________________ Phone ___________ Street _________________________________________ P0 Box/Route Box __________________ II 1City State/Province ________________Zip _________________ 1IMAA AMA Number ___________MAAC _________Chapter L TO IMAA Secretary DONE VINEYARD 205k Hiliciale Road a KS 67401 FF Indoor/Tenny Continued page 110 later Refer October 1993 column list site contact persons BE SAFE Check contest status before leaving home CaliforniaBurbank area Blacksheep Exhibition Squadron have Cat Indoor meets Luther Burbank Middle School second Friday month 7 pm-l0 pm Tony Naccarato 2121 N Hollywood Way Burbank CA 91507 Tel 818 842-5062 CaliforniaLos Angeles area Possible sessions 60-foot Downtown LA Armory Stadium Way Contact Otto Kuhni Tel 213 872-0882 CaliforniaMann County 20 miles north San Francisco Year-round minicontests 8 am-2 pm fourth Sunday month site standard basketball court 28 feet clear Contact Tom Brennan 21326 Via Colombard Sonoma CA 95476 Tel 707 938-2893 CaliforniaSan Diego Fun Fly Scale sessions second Friday month monthly sessions fourth Friday Colina Del Sol Community Center Cat 5316 Orange Ave San Diego Howard Haupt 3860 Ecochee Ave San Diego CA 92117 Tel 619 272-5656 ConnecticutGlastonbury Flying sessions Glastonbury High School Gym George Armstead 89 Harvest Lane Glastonbury CT 06037 Tel 203 633-7836 FloridaMeets sponsored Miami Indoor Airplane Modelers Association Contact John Martin 2180 Tigertail Ave Miami FL 33133 Tel 305 858-6363 Continued page 151 Cressline Models Inc QUIcKIE $10995 VIGGEN $33995 1441 N Mayfair Road aukee WI 53226 257-1923 Fax 414 771-2092 7iI7 MCI VISA AF-5E AGGRESSOR tq*O O * AMERIcAS FAVORITE $15495 * 1/8 Scale 70 LX 1/5 Scale 626 WS 4-5 Channel 40 Eng Channel 34 OZAC Sport Scale Canard ~jjadjeai7a TIGERSIIARK $339 95* 1/8 Scale 70 Lx 48 annel 33 oz Wing Load 712 aq area $329 95* 1/16 Scale 67 x 64 WS 4-9 Channel 28 oz Wing Load 832 aq area PRICES SUBJECT 70 CHANGEPIus Shipping & HandlIng January1994 119 2 order call Eric Sanders 299-7684 5 pm-iO pm EST Monday-Friday day Sat Sun 1W t IC flS 511111 CAD airfoil editor-move coordinatee w/mouae create new points round out leading edgee undo mode 64x zoom pan mode coordinate 0 mode ahowa current cursor position etc use windowing interface Pop up text editor document airfoil changes-saved coordinates ulates elliptical planform rib lengtha Chord queue allows templates several chord lengths printed out unattended edit coordinates Pop-up calculator conversions s foam outline screen optimize template height Customizable screen colors are airfoils screen printer using overlay mode ts mirror image Calculates panel volume & surface area aide weight estimations Supports dot matrix laxer let printers Calculates projected panel area airfoil cross sectional area perimeter length tive negative washout Modity airfoils changing camber thicknessmirroring combining tops bottoms different airfoils Interpolates between different root tip airfoils position within wing panel uts DXF file Both scaled unscaled hi-ran screen preview modes her\Cut ItmI calculator much much morel. Remember wine accurate temolates CompuFoil Profeasional-$65 Airfoil Library w/135 airfoils-$1O S&H add $3 Also svailable-CompuFoil Standard-$25 CompuFoil Plus-$45 Demo Disk-$5 refundable order wilt compatability product ordering information 3904 Traine Dr. Kettering OH. 45429 09 2 J55 2 Fl III 1rxthlof/tsc/0ly 03 K FF Indoor/Tenny Continued page 119 IowaCedar Rapids Regular scheduled unsanctioned flying sessions Nov 93 through March 94 28-foot ceiling Paul Mcllrath 1524 48th St NE Cedar Rapids IA 52402 Tel 319 393-4677 KansasTopeka Topeka still looking site replace Stone Hangar Check periodically Jack Koeblar 3425 SW Arrowhead Rd Topeka KS 66614-3485 Tel 913 272-8439 see what find. KansasWichita Session Friends University 28-foot site 12-6 pm Planned first weekend month subject approval Jan 94 through March 94 Normal schedule heavy events 12-2 pm lightweight events 2 pm-6 pm Contact Stan Chilton 725 E Lincoln Wichita KS 67211-3302 Tel 316 686-9634 KentuckyLouisville Flying sessions Tuesday Sawyer Park site 11 am- 1 pm Also Saturday month subject military schedules Kentucky Air National Guard suite 10 am-2 pm Contact Mason Plank 3207 Oriole Dr Louisville KY 40213 Tel 502 634-8191 New YorkBrooklyn Indoor contests March April 1994 Blue Nose Hangar Floyd Bennett Field Brooklyn Site has 150- x 450-foot floor 45 feet rafters field truss beam easy retrieval Contact Don Ross 38 Churchill Rd Cresskill NJ 07626 Tel 201 568-5272 PennsylvaniaPhiladelphia Flying Byrn Athen Fairmont Park Joe Krush 409 Warner Rd Wayne PA 19087 Tel 215 688-3027 OklahomaOklahoma City Sessions contests planned third weekend month Jan 94-March 94 Jim Belson 4933 NW 29th Oklahoma City OK 73129 Tel 405 946-1093 OklahomaTulsa Sessions/contests planned second weekend month Jan 14 Feb 12 March 12 Roy OMara 9120 7th St Tulsa OK 74112 Tel 918 835-6880 MiniStick Hints Living room trim During final days International MiniStick Postal Jim Clem checked out recreation room house hoped make up having regular flying session during duration postal meet room 19 feet square peaked ceiling about 14 feet high ceiling specification called height measurement made five-meter circle checked out 10 feet inch times Jims best flight 417 turned 344 Normally models fly about same realized too late subtle difference trim between two models model still trimmed 26-foot Bedford site did 700 December Jims model trimmed slightly nose-up normal Bedford trim difference showed ceiling contacts model built up too much speed between contacts third contact usually worked its way corner Jims model did classic stall-and-turn tightened circle enough get near peak Once stopped climbing usually centered four feet higher same stage flight power factor Both models shared same flight strategyflying entirely flat part torque curve shown Figure 1 represents typical torque curve critical values marked critical values represent approximate ideal Launch torque initially chosen climb rate minimize rate climb length ceiling contact B Torque first ceiling contact C Level-flight torque end climbing D Touchdown torque model climbs torque drops C bounces during torque range B C proper trim ceiling lots luck torque will reach point C model centered well enough land floor final factor consider choosing rubber 1oop length cross-section hold number turns expended between torque levels D model landing too turns shorten loop lighten model effectively lengthen first part curve about flat ceiling really smooth flat ceiling can potentially give higher duration room large enough major difference two ceiling types model can fly slightly faster long can ceiling-scrub getting too far off-center Otherwise must fly slowlyenough hesitate ceiling contact made Additional washin left wingtip should cause tip stall model turns tightly Some models widen turn contact flat ceiling bottom line high livingroom times require extensive flight testing special adjustments precise rubber selection higher ceilings Most likely best rubber cross-section will larger feasible use higher ceilings shortest possible 1oop will give required number turns over range torque used CyA Comments following abstracted article SAM 86 Speaks original material credited Woodcuts magazine Should Modelers Worry About Molecule Growth Some glues fail because curing process causes molecules grow large interconnecting bonds reduced number until material easily fractures particular certain cyanoacrylares virtually turn powder Some rapidly curing cyanoacrylates continue cure until molecules become large no longer weld other cohesion two surfaces intended held together adhesion better-known cyanoacrylates formulated limit such molecular growth Among best 3M Hot Stuff lines As general rule slower-curing cyanoacrylates form much smaller molecules An extra minute curing time can contribute substantially long-term strength Indoor Props prop almost important part Indoor model half important part prop/rubber combination Any Indoor model competitive weight reasonable trim will well long airframe stiff enough hold adjustments point prop rubber combination makes difference Basic prop theory begins definition pitch formula Pitch blade element 6 x tan angle x diameter Can illustrated solving pitch angle vs diameter Pitch nches DiameterBlade Angle 2726 4 579 6 467 8385 10 325 12 279 14 16 Angle 450 DiameterPitch 2628 4126 6188 8251 10314 12377 24414440 21716503 300 Pitch 363 725 109 145 181 218 254 290 charts highlight difference between standard true-pitch helicalpitch prop constant-angle prop constant-angle props computed table have flat non-twisted blades mounted either 30 45 degrees obvious thing note about constant angle prop blade tips would very much pulling helical-pitch prop computed above could built carved block like Figure 2 key fact remember January1994 151 FF Indoor/Tenny Continued page 151 about prop blades built form angular difference between two blade stations remain same blade rotated shortened discussed below Modifying Existing Props us have constructed props using tissue socket hub allows us change prop blades rotate blades different angle matched sets different diameter possible tailor old props new models Simply rotating blades new angle makes minor adjustments existing prop Lets examine what happens 20inch-pitch prop computed above Assume have cut inch out center prop spars leave 15 inches diameter Using tissue sockets can splice two blades together following chart compares blade angle vs diameter data previously shown pitch resulting four kinds change prop blade can rotated lower angle higher angle can shortened also can shortened rotated higher angle computations show results rotating blade five degrees five degrees less shortening 16-inch diameter 15 inches blade one-halfinch shorter right column combines effect shortening blade increasing angle five degrees case computation begins angle blade element shown original chart computed result same segment shown change condition right CL AerobaticslMcMillan Continued page 123 Tech Tips Last year discussed sealing control surface hinge lines extremely effective trimming tool Because chances good will help no question should try new planes Although doesnt help planes wont know until give go benefit prevention funnies Windy Urtnowski calls outboard wing rebuilt Caudron popped up top inside outside rounds First sealed CL Speed/Lee Continued paqe 125 needle setting wont change Different pins required different props stored hole end block kept threaded brass plug terrific accessory ease prop modification increase flight repeatability Another interesting thing Nats Bill Wisniewskis 21 K&B engine used grandson Mike 21 Sport Speed Bill used sleeve piston Sportster 20 drum rotor space between hinges wing still behaved same desperation ran continuous strip root tip funny gone best could figure out hinge cutouts tip bleeding air small things can real killers main reason brought up pass information found unlikely place using 3Ms plastic tape satisfactory adhesive effective because low tack however since tape bit thick controls somewhat stiff led search something better Continued page 165 rear end used marine version engine built ball-bearing crankshaft crankcase trouble conrodthe bronze bushing kept going outso pressed high-silicon aluminum bushing worked great engine ran very well K&B engines now have clearance conrods much 005 being used lower end engine performance reliability better ever See Nats photos couple new engines Wiley 40 Jett 40 Ill try get performance information future column h itch after change DiaBlade Angle 2 726 4 579 6 467 8 385 10 325 12 279 14 244 16 217 152 166 168 166 163 159 155 150 266 246 239 238 241 244 248 253 15 dia 149 175 183 187 190 191 192 214 215 219 224 229 234 239 Figure 3 graphs pitch distribution rotated blades comparison standard 20-inch helical blade using variable pitch props think about widely pitch varies over range allow angle change may profit planning what pitch block build blades use high-pitch block equal upper limit setting lower settings will have center blade doing work efficient Im sure anyone knows sure interesting think about Model Aviation 4
Edition: Model Aviation - 1994/01
Page Numbers: 110, 119, 151, 152
FREE FLIGHT INDOOR KIBBIE DOME REPORT Much following information taken report hy Leo Mary Smothers including photos discussed below spite colder-than-usual temperatures kept times down everyone good time Contestants Dallas Jim Clem St Louis Larry Coslick others over West Coast showed up three days intense flying contest format resembles used NIMAS Annual Record Trials flown West Baden mid-1970s format fly event events interest mostall three days suits emphasis informal flying ngid contest schedule Wally Miller originated Easy B developing new event intended help bridge gap between Easy B FlD models Wally calls event PRO-20 set up limits monoplane 68 square inches projected area 50% max stab maximum projected wingspan 20 inches Wallys model first break 20 minutes Andy Tagliafico logged best time 2628 Design goal 30 minutes Some top times events Intermediate Stick Wally Miller 2445 FiD two flight total Steve Brown 8304 Manhattan Cabin Larry Coslick 1057 Easy B Larry Coslick 2238 Pennyplane John Lenderman 1211 Limited Pennyplane John Lenderman 1101 Ornithopter Warren Williams 743 ROG Larry Coslick 1057 MiniStick Andy Tagliafico 1044 Federated ROG Andy Tagliafico 810 Perhaps best yardstick conditions times often closely parallel winning times USIC very similar site years best USIC Pennyplane time 1611 Bernie Wisniewski John Lendermans 1211 same event Kibbie significantly lower Tan II new crop Tan rubber out Figure 1 BA o Four critical torque values living room flying Climb C bounce B C Text has details year has much lighter color previous hatches new tan has nickname Fran Clem said looks like fettucini Fettucini oops Tan II has different characteristics Tan stretches takes turns apparently has higher energy storage high end torque curve much steeper earlier Tan steeper high end torque slope Pirelli Although Tan II still takes lot getting used number better fliers year did very well using Larry Coslick notes Tan II seems less tolerant low temperatures Tan also feels similar times turns available using shorter loops larger cross-sections changes made similar performance motor Tan used 16-inch 1oop 044 width compared 14-inch loop 048 Tan II quick calculation indicates new motor about four percent lighter would fair try compare energy storage specific energy energy/unit weight basis numbers Some testers report five ten percent higher specific energy storage capabilities over best batches Tan Given higher energy steeper torque slope would reasonable expect Tan II have better utility lower ceilings due longer mid-torque slope Figure 2 Pitchpi x 2 x L x jr/wi Carved prop block helical pitch distribution Angular difference between two stations remains same Tan II model can use extreme torque burst efficiently launching absolute max torque should enable high-ceiling performance good also Good Idea year Indoor contests held Oregon accompanied seminars after flying sessions Noted fliers give excellent programs variety topics fliers area arent very well known other areas always well come contests other areas year speakers included Lew Gitlow Andy Tagliafico Ed B array Hying opportunities listings below have new information available CDs please fill dates after March 1993 Continued page 119 Figure 3 Pitch distributionhelical plus five degrees Diameter 246610121416 II II Pitch distribution 20 helical pitch Pitch distributionhelical minus five degrees Pitch distribution comparison blades 20-mci pitch helical prop blades twisted fbi degrees higher five degrees lower angle 110 Model Aviation Allisons Skylark SRX-1 Flying Aces Club FAC Jumbo Scale model cruises slowly past camera Larry Coslick winding Manhattan Cabin model Kibbie Dome First place 1057 Mary Smothers photo John Lenderman tweaks winning Limited Pennnyplane model Kibbie Winning time 1101 5 Join theGiantsHelp Promote INon-CompetitiveI HIG inffII s.c, Flying Large RIC Air Cra ft I IMAA membership includes quarterly magazine High Flight I MEMBERSHIP APPUCAllON IJ NEW fJ RENEWAL Date19I Yearly Dues$1500 USA $2000 US Canada & Mexico $3000 US ElsewhereI Make CHECK MONEY ORDER Payable INTERNAllONAL MINIAlURE AIRCRAFT ASSOCIATION INC I Name _________________ Phone ___________ Street _________________________________________ P0 Box/Route Box __________________ II 1City State/Province ________________Zip _________________ 1IMAA AMA Number ___________MAAC _________Chapter L TO IMAA Secretary DONE VINEYARD 205k Hiliciale Road a KS 67401 FF Indoor/Tenny Continued page 110 later Refer October 1993 column list site contact persons BE SAFE Check contest status before leaving home CaliforniaBurbank area Blacksheep Exhibition Squadron have Cat Indoor meets Luther Burbank Middle School second Friday month 7 pm-l0 pm Tony Naccarato 2121 N Hollywood Way Burbank CA 91507 Tel 818 842-5062 CaliforniaLos Angeles area Possible sessions 60-foot Downtown LA Armory Stadium Way Contact Otto Kuhni Tel 213 872-0882 CaliforniaMann County 20 miles north San Francisco Year-round minicontests 8 am-2 pm fourth Sunday month site standard basketball court 28 feet clear Contact Tom Brennan 21326 Via Colombard Sonoma CA 95476 Tel 707 938-2893 CaliforniaSan Diego Fun Fly Scale sessions second Friday month monthly sessions fourth Friday Colina Del Sol Community Center Cat 5316 Orange Ave San Diego Howard Haupt 3860 Ecochee Ave San Diego CA 92117 Tel 619 272-5656 ConnecticutGlastonbury Flying sessions Glastonbury High School Gym George Armstead 89 Harvest Lane Glastonbury CT 06037 Tel 203 633-7836 FloridaMeets sponsored Miami Indoor Airplane Modelers Association Contact John Martin 2180 Tigertail Ave Miami FL 33133 Tel 305 858-6363 Continued page 151 Cressline Models Inc QUIcKIE $10995 VIGGEN $33995 1441 N Mayfair Road aukee WI 53226 257-1923 Fax 414 771-2092 7iI7 MCI VISA AF-5E AGGRESSOR tq*O O * AMERIcAS FAVORITE $15495 * 1/8 Scale 70 LX 1/5 Scale 626 WS 4-5 Channel 40 Eng Channel 34 OZAC Sport Scale Canard ~jjadjeai7a TIGERSIIARK $339 95* 1/8 Scale 70 Lx 48 annel 33 oz Wing Load 712 aq area $329 95* 1/16 Scale 67 x 64 WS 4-9 Channel 28 oz Wing Load 832 aq area PRICES SUBJECT 70 CHANGEPIus Shipping & HandlIng January1994 119 2 order call Eric Sanders 299-7684 5 pm-iO pm EST Monday-Friday day Sat Sun 1W t IC flS 511111 CAD airfoil editor-move coordinatee w/mouae create new points round out leading edgee undo mode 64x zoom pan mode coordinate 0 mode ahowa current cursor position etc use windowing interface Pop up text editor document airfoil changes-saved coordinates ulates elliptical planform rib lengtha Chord queue allows templates several chord lengths printed out unattended edit coordinates Pop-up calculator conversions s foam outline screen optimize template height Customizable screen colors are airfoils screen printer using overlay mode ts mirror image Calculates panel volume & surface area aide weight estimations Supports dot matrix laxer let printers Calculates projected panel area airfoil cross sectional area perimeter length tive negative washout Modity airfoils changing camber thicknessmirroring combining tops bottoms different airfoils Interpolates between different root tip airfoils position within wing panel uts DXF file Both scaled unscaled hi-ran screen preview modes her\Cut ItmI calculator much much morel. Remember wine accurate temolates CompuFoil Profeasional-$65 Airfoil Library w/135 airfoils-$1O S&H add $3 Also svailable-CompuFoil Standard-$25 CompuFoil Plus-$45 Demo Disk-$5 refundable order wilt compatability product ordering information 3904 Traine Dr. Kettering OH. 45429 09 2 J55 2 Fl III 1rxthlof/tsc/0ly 03 K FF Indoor/Tenny Continued page 119 IowaCedar Rapids Regular scheduled unsanctioned flying sessions Nov 93 through March 94 28-foot ceiling Paul Mcllrath 1524 48th St NE Cedar Rapids IA 52402 Tel 319 393-4677 KansasTopeka Topeka still looking site replace Stone Hangar Check periodically Jack Koeblar 3425 SW Arrowhead Rd Topeka KS 66614-3485 Tel 913 272-8439 see what find. KansasWichita Session Friends University 28-foot site 12-6 pm Planned first weekend month subject approval Jan 94 through March 94 Normal schedule heavy events 12-2 pm lightweight events 2 pm-6 pm Contact Stan Chilton 725 E Lincoln Wichita KS 67211-3302 Tel 316 686-9634 KentuckyLouisville Flying sessions Tuesday Sawyer Park site 11 am- 1 pm Also Saturday month subject military schedules Kentucky Air National Guard suite 10 am-2 pm Contact Mason Plank 3207 Oriole Dr Louisville KY 40213 Tel 502 634-8191 New YorkBrooklyn Indoor contests March April 1994 Blue Nose Hangar Floyd Bennett Field Brooklyn Site has 150- x 450-foot floor 45 feet rafters field truss beam easy retrieval Contact Don Ross 38 Churchill Rd Cresskill NJ 07626 Tel 201 568-5272 PennsylvaniaPhiladelphia Flying Byrn Athen Fairmont Park Joe Krush 409 Warner Rd Wayne PA 19087 Tel 215 688-3027 OklahomaOklahoma City Sessions contests planned third weekend month Jan 94-March 94 Jim Belson 4933 NW 29th Oklahoma City OK 73129 Tel 405 946-1093 OklahomaTulsa Sessions/contests planned second weekend month Jan 14 Feb 12 March 12 Roy OMara 9120 7th St Tulsa OK 74112 Tel 918 835-6880 MiniStick Hints Living room trim During final days International MiniStick Postal Jim Clem checked out recreation room house hoped make up having regular flying session during duration postal meet room 19 feet square peaked ceiling about 14 feet high ceiling specification called height measurement made five-meter circle checked out 10 feet inch times Jims best flight 417 turned 344 Normally models fly about same realized too late subtle difference trim between two models model still trimmed 26-foot Bedford site did 700 December Jims model trimmed slightly nose-up normal Bedford trim difference showed ceiling contacts model built up too much speed between contacts third contact usually worked its way corner Jims model did classic stall-and-turn tightened circle enough get near peak Once stopped climbing usually centered four feet higher same stage flight power factor Both models shared same flight strategyflying entirely flat part torque curve shown Figure 1 represents typical torque curve critical values marked critical values represent approximate ideal Launch torque initially chosen climb rate minimize rate climb length ceiling contact B Torque first ceiling contact C Level-flight torque end climbing D Touchdown torque model climbs torque drops C bounces during torque range B C proper trim ceiling lots luck torque will reach point C model centered well enough land floor final factor consider choosing rubber 1oop length cross-section hold number turns expended between torque levels D model landing too turns shorten loop lighten model effectively lengthen first part curve about flat ceiling really smooth flat ceiling can potentially give higher duration room large enough major difference two ceiling types model can fly slightly faster long can ceiling-scrub getting too far off-center Otherwise must fly slowlyenough hesitate ceiling contact made Additional washin left wingtip should cause tip stall model turns tightly Some models widen turn contact flat ceiling bottom line high livingroom times require extensive flight testing special adjustments precise rubber selection higher ceilings Most likely best rubber cross-section will larger feasible use higher ceilings shortest possible 1oop will give required number turns over range torque used CyA Comments following abstracted article SAM 86 Speaks original material credited Woodcuts magazine Should Modelers Worry About Molecule Growth Some glues fail because curing process causes molecules grow large interconnecting bonds reduced number until material easily fractures particular certain cyanoacrylares virtually turn powder Some rapidly curing cyanoacrylates continue cure until molecules become large no longer weld other cohesion two surfaces intended held together adhesion better-known cyanoacrylates formulated limit such molecular growth Among best 3M Hot Stuff lines As general rule slower-curing cyanoacrylates form much smaller molecules An extra minute curing time can contribute substantially long-term strength Indoor Props prop almost important part Indoor model half important part prop/rubber combination Any Indoor model competitive weight reasonable trim will well long airframe stiff enough hold adjustments point prop rubber combination makes difference Basic prop theory begins definition pitch formula Pitch blade element 6 x tan angle x diameter Can illustrated solving pitch angle vs diameter Pitch nches DiameterBlade Angle 2726 4 579 6 467 8385 10 325 12 279 14 16 Angle 450 DiameterPitch 2628 4126 6188 8251 10314 12377 24414440 21716503 300 Pitch 363 725 109 145 181 218 254 290 charts highlight difference between standard true-pitch helicalpitch prop constant-angle prop constant-angle props computed table have flat non-twisted blades mounted either 30 45 degrees obvious thing note about constant angle prop blade tips would very much pulling helical-pitch prop computed above could built carved block like Figure 2 key fact remember January1994 151 FF Indoor/Tenny Continued page 151 about prop blades built form angular difference between two blade stations remain same blade rotated shortened discussed below Modifying Existing Props us have constructed props using tissue socket hub allows us change prop blades rotate blades different angle matched sets different diameter possible tailor old props new models Simply rotating blades new angle makes minor adjustments existing prop Lets examine what happens 20inch-pitch prop computed above Assume have cut inch out center prop spars leave 15 inches diameter Using tissue sockets can splice two blades together following chart compares blade angle vs diameter data previously shown pitch resulting four kinds change prop blade can rotated lower angle higher angle can shortened also can shortened rotated higher angle computations show results rotating blade five degrees five degrees less shortening 16-inch diameter 15 inches blade one-halfinch shorter right column combines effect shortening blade increasing angle five degrees case computation begins angle blade element shown original chart computed result same segment shown change condition right CL AerobaticslMcMillan Continued page 123 Tech Tips Last year discussed sealing control surface hinge lines extremely effective trimming tool Because chances good will help no question should try new planes Although doesnt help planes wont know until give go benefit prevention funnies Windy Urtnowski calls outboard wing rebuilt Caudron popped up top inside outside rounds First sealed CL Speed/Lee Continued paqe 125 needle setting wont change Different pins required different props stored hole end block kept threaded brass plug terrific accessory ease prop modification increase flight repeatability Another interesting thing Nats Bill Wisniewskis 21 K&B engine used grandson Mike 21 Sport Speed Bill used sleeve piston Sportster 20 drum rotor space between hinges wing still behaved same desperation ran continuous strip root tip funny gone best could figure out hinge cutouts tip bleeding air small things can real killers main reason brought up pass information found unlikely place using 3Ms plastic tape satisfactory adhesive effective because low tack however since tape bit thick controls somewhat stiff led search something better Continued page 165 rear end used marine version engine built ball-bearing crankshaft crankcase trouble conrodthe bronze bushing kept going outso pressed high-silicon aluminum bushing worked great engine ran very well K&B engines now have clearance conrods much 005 being used lower end engine performance reliability better ever See Nats photos couple new engines Wiley 40 Jett 40 Ill try get performance information future column h itch after change DiaBlade Angle 2 726 4 579 6 467 8 385 10 325 12 279 14 244 16 217 152 166 168 166 163 159 155 150 266 246 239 238 241 244 248 253 15 dia 149 175 183 187 190 191 192 214 215 219 224 229 234 239 Figure 3 graphs pitch distribution rotated blades comparison standard 20-inch helical blade using variable pitch props think about widely pitch varies over range allow angle change may profit planning what pitch block build blades use high-pitch block equal upper limit setting lower settings will have center blade doing work efficient Im sure anyone knows sure interesting think about Model Aviation 4
Edition: Model Aviation - 1994/01
Page Numbers: 110, 119, 151, 152
FREE FLIGHT INDOOR KIBBIE DOME REPORT Much following information taken report hy Leo Mary Smothers including photos discussed below spite colder-than-usual temperatures kept times down everyone good time Contestants Dallas Jim Clem St Louis Larry Coslick others over West Coast showed up three days intense flying contest format resembles used NIMAS Annual Record Trials flown West Baden mid-1970s format fly event events interest mostall three days suits emphasis informal flying ngid contest schedule Wally Miller originated Easy B developing new event intended help bridge gap between Easy B FlD models Wally calls event PRO-20 set up limits monoplane 68 square inches projected area 50% max stab maximum projected wingspan 20 inches Wallys model first break 20 minutes Andy Tagliafico logged best time 2628 Design goal 30 minutes Some top times events Intermediate Stick Wally Miller 2445 FiD two flight total Steve Brown 8304 Manhattan Cabin Larry Coslick 1057 Easy B Larry Coslick 2238 Pennyplane John Lenderman 1211 Limited Pennyplane John Lenderman 1101 Ornithopter Warren Williams 743 ROG Larry Coslick 1057 MiniStick Andy Tagliafico 1044 Federated ROG Andy Tagliafico 810 Perhaps best yardstick conditions times often closely parallel winning times USIC very similar site years best USIC Pennyplane time 1611 Bernie Wisniewski John Lendermans 1211 same event Kibbie significantly lower Tan II new crop Tan rubber out Figure 1 BA o Four critical torque values living room flying Climb C bounce B C Text has details year has much lighter color previous hatches new tan has nickname Fran Clem said looks like fettucini Fettucini oops Tan II has different characteristics Tan stretches takes turns apparently has higher energy storage high end torque curve much steeper earlier Tan steeper high end torque slope Pirelli Although Tan II still takes lot getting used number better fliers year did very well using Larry Coslick notes Tan II seems less tolerant low temperatures Tan also feels similar times turns available using shorter loops larger cross-sections changes made similar performance motor Tan used 16-inch 1oop 044 width compared 14-inch loop 048 Tan II quick calculation indicates new motor about four percent lighter would fair try compare energy storage specific energy energy/unit weight basis numbers Some testers report five ten percent higher specific energy storage capabilities over best batches Tan Given higher energy steeper torque slope would reasonable expect Tan II have better utility lower ceilings due longer mid-torque slope Figure 2 Pitchpi x 2 x L x jr/wi Carved prop block helical pitch distribution Angular difference between two stations remains same Tan II model can use extreme torque burst efficiently launching absolute max torque should enable high-ceiling performance good also Good Idea year Indoor contests held Oregon accompanied seminars after flying sessions Noted fliers give excellent programs variety topics fliers area arent very well known other areas always well come contests other areas year speakers included Lew Gitlow Andy Tagliafico Ed B array Hying opportunities listings below have new information available CDs please fill dates after March 1993 Continued page 119 Figure 3 Pitch distributionhelical plus five degrees Diameter 246610121416 II II Pitch distribution 20 helical pitch Pitch distributionhelical minus five degrees Pitch distribution comparison blades 20-mci pitch helical prop blades twisted fbi degrees higher five degrees lower angle 110 Model Aviation Allisons Skylark SRX-1 Flying Aces Club FAC Jumbo Scale model cruises slowly past camera Larry Coslick winding Manhattan Cabin model Kibbie Dome First place 1057 Mary Smothers photo John Lenderman tweaks winning Limited Pennnyplane model Kibbie Winning time 1101 5 Join theGiantsHelp Promote INon-CompetitiveI HIG inffII s.c, Flying Large RIC Air Cra ft I IMAA membership includes quarterly magazine High Flight I MEMBERSHIP APPUCAllON IJ NEW fJ RENEWAL Date19I Yearly Dues$1500 USA $2000 US Canada & Mexico $3000 US ElsewhereI Make CHECK MONEY ORDER Payable INTERNAllONAL MINIAlURE AIRCRAFT ASSOCIATION INC I Name _________________ Phone ___________ Street _________________________________________ P0 Box/Route Box __________________ II 1City State/Province ________________Zip _________________ 1IMAA AMA Number ___________MAAC _________Chapter L TO IMAA Secretary DONE VINEYARD 205k Hiliciale Road a KS 67401 FF Indoor/Tenny Continued page 110 later Refer October 1993 column list site contact persons BE SAFE Check contest status before leaving home CaliforniaBurbank area Blacksheep Exhibition Squadron have Cat Indoor meets Luther Burbank Middle School second Friday month 7 pm-l0 pm Tony Naccarato 2121 N Hollywood Way Burbank CA 91507 Tel 818 842-5062 CaliforniaLos Angeles area Possible sessions 60-foot Downtown LA Armory Stadium Way Contact Otto Kuhni Tel 213 872-0882 CaliforniaMann County 20 miles north San Francisco Year-round minicontests 8 am-2 pm fourth Sunday month site standard basketball court 28 feet clear Contact Tom Brennan 21326 Via Colombard Sonoma CA 95476 Tel 707 938-2893 CaliforniaSan Diego Fun Fly Scale sessions second Friday month monthly sessions fourth Friday Colina Del Sol Community Center Cat 5316 Orange Ave San Diego Howard Haupt 3860 Ecochee Ave San Diego CA 92117 Tel 619 272-5656 ConnecticutGlastonbury Flying sessions Glastonbury High School Gym George Armstead 89 Harvest Lane Glastonbury CT 06037 Tel 203 633-7836 FloridaMeets sponsored Miami Indoor Airplane Modelers Association Contact John Martin 2180 Tigertail Ave Miami FL 33133 Tel 305 858-6363 Continued page 151 Cressline Models Inc QUIcKIE $10995 VIGGEN $33995 1441 N Mayfair Road aukee WI 53226 257-1923 Fax 414 771-2092 7iI7 MCI VISA AF-5E AGGRESSOR tq*O O * AMERIcAS FAVORITE $15495 * 1/8 Scale 70 LX 1/5 Scale 626 WS 4-5 Channel 40 Eng Channel 34 OZAC Sport Scale Canard ~jjadjeai7a TIGERSIIARK $339 95* 1/8 Scale 70 Lx 48 annel 33 oz Wing Load 712 aq area $329 95* 1/16 Scale 67 x 64 WS 4-9 Channel 28 oz Wing Load 832 aq area PRICES SUBJECT 70 CHANGEPIus Shipping & HandlIng January1994 119 2 order call Eric Sanders 299-7684 5 pm-iO pm EST Monday-Friday day Sat Sun 1W t IC flS 511111 CAD airfoil editor-move coordinatee w/mouae create new points round out leading edgee undo mode 64x zoom pan mode coordinate 0 mode ahowa current cursor position etc use windowing interface Pop up text editor document airfoil changes-saved coordinates ulates elliptical planform rib lengtha Chord queue allows templates several chord lengths printed out unattended edit coordinates Pop-up calculator conversions s foam outline screen optimize template height Customizable screen colors are airfoils screen printer using overlay mode ts mirror image Calculates panel volume & surface area aide weight estimations Supports dot matrix laxer let printers Calculates projected panel area airfoil cross sectional area perimeter length tive negative washout Modity airfoils changing camber thicknessmirroring combining tops bottoms different airfoils Interpolates between different root tip airfoils position within wing panel uts DXF file Both scaled unscaled hi-ran screen preview modes her\Cut ItmI calculator much much morel. Remember wine accurate temolates CompuFoil Profeasional-$65 Airfoil Library w/135 airfoils-$1O S&H add $3 Also svailable-CompuFoil Standard-$25 CompuFoil Plus-$45 Demo Disk-$5 refundable order wilt compatability product ordering information 3904 Traine Dr. Kettering OH. 45429 09 2 J55 2 Fl III 1rxthlof/tsc/0ly 03 K FF Indoor/Tenny Continued page 119 IowaCedar Rapids Regular scheduled unsanctioned flying sessions Nov 93 through March 94 28-foot ceiling Paul Mcllrath 1524 48th St NE Cedar Rapids IA 52402 Tel 319 393-4677 KansasTopeka Topeka still looking site replace Stone Hangar Check periodically Jack Koeblar 3425 SW Arrowhead Rd Topeka KS 66614-3485 Tel 913 272-8439 see what find. KansasWichita Session Friends University 28-foot site 12-6 pm Planned first weekend month subject approval Jan 94 through March 94 Normal schedule heavy events 12-2 pm lightweight events 2 pm-6 pm Contact Stan Chilton 725 E Lincoln Wichita KS 67211-3302 Tel 316 686-9634 KentuckyLouisville Flying sessions Tuesday Sawyer Park site 11 am- 1 pm Also Saturday month subject military schedules Kentucky Air National Guard suite 10 am-2 pm Contact Mason Plank 3207 Oriole Dr Louisville KY 40213 Tel 502 634-8191 New YorkBrooklyn Indoor contests March April 1994 Blue Nose Hangar Floyd Bennett Field Brooklyn Site has 150- x 450-foot floor 45 feet rafters field truss beam easy retrieval Contact Don Ross 38 Churchill Rd Cresskill NJ 07626 Tel 201 568-5272 PennsylvaniaPhiladelphia Flying Byrn Athen Fairmont Park Joe Krush 409 Warner Rd Wayne PA 19087 Tel 215 688-3027 OklahomaOklahoma City Sessions contests planned third weekend month Jan 94-March 94 Jim Belson 4933 NW 29th Oklahoma City OK 73129 Tel 405 946-1093 OklahomaTulsa Sessions/contests planned second weekend month Jan 14 Feb 12 March 12 Roy OMara 9120 7th St Tulsa OK 74112 Tel 918 835-6880 MiniStick Hints Living room trim During final days International MiniStick Postal Jim Clem checked out recreation room house hoped make up having regular flying session during duration postal meet room 19 feet square peaked ceiling about 14 feet high ceiling specification called height measurement made five-meter circle checked out 10 feet inch times Jims best flight 417 turned 344 Normally models fly about same realized too late subtle difference trim between two models model still trimmed 26-foot Bedford site did 700 December Jims model trimmed slightly nose-up normal Bedford trim difference showed ceiling contacts model built up too much speed between contacts third contact usually worked its way corner Jims model did classic stall-and-turn tightened circle enough get near peak Once stopped climbing usually centered four feet higher same stage flight power factor Both models shared same flight strategyflying entirely flat part torque curve shown Figure 1 represents typical torque curve critical values marked critical values represent approximate ideal Launch torque initially chosen climb rate minimize rate climb length ceiling contact B Torque first ceiling contact C Level-flight torque end climbing D Touchdown torque model climbs torque drops C bounces during torque range B C proper trim ceiling lots luck torque will reach point C model centered well enough land floor final factor consider choosing rubber 1oop length cross-section hold number turns expended between torque levels D model landing too turns shorten loop lighten model effectively lengthen first part curve about flat ceiling really smooth flat ceiling can potentially give higher duration room large enough major difference two ceiling types model can fly slightly faster long can ceiling-scrub getting too far off-center Otherwise must fly slowlyenough hesitate ceiling contact made Additional washin left wingtip should cause tip stall model turns tightly Some models widen turn contact flat ceiling bottom line high livingroom times require extensive flight testing special adjustments precise rubber selection higher ceilings Most likely best rubber cross-section will larger feasible use higher ceilings shortest possible 1oop will give required number turns over range torque used CyA Comments following abstracted article SAM 86 Speaks original material credited Woodcuts magazine Should Modelers Worry About Molecule Growth Some glues fail because curing process causes molecules grow large interconnecting bonds reduced number until material easily fractures particular certain cyanoacrylares virtually turn powder Some rapidly curing cyanoacrylates continue cure until molecules become large no longer weld other cohesion two surfaces intended held together adhesion better-known cyanoacrylates formulated limit such molecular growth Among best 3M Hot Stuff lines As general rule slower-curing cyanoacrylates form much smaller molecules An extra minute curing time can contribute substantially long-term strength Indoor Props prop almost important part Indoor model half important part prop/rubber combination Any Indoor model competitive weight reasonable trim will well long airframe stiff enough hold adjustments point prop rubber combination makes difference Basic prop theory begins definition pitch formula Pitch blade element 6 x tan angle x diameter Can illustrated solving pitch angle vs diameter Pitch nches DiameterBlade Angle 2726 4 579 6 467 8385 10 325 12 279 14 16 Angle 450 DiameterPitch 2628 4126 6188 8251 10314 12377 24414440 21716503 300 Pitch 363 725 109 145 181 218 254 290 charts highlight difference between standard true-pitch helicalpitch prop constant-angle prop constant-angle props computed table have flat non-twisted blades mounted either 30 45 degrees obvious thing note about constant angle prop blade tips would very much pulling helical-pitch prop computed above could built carved block like Figure 2 key fact remember January1994 151 FF Indoor/Tenny Continued page 151 about prop blades built form angular difference between two blade stations remain same blade rotated shortened discussed below Modifying Existing Props us have constructed props using tissue socket hub allows us change prop blades rotate blades different angle matched sets different diameter possible tailor old props new models Simply rotating blades new angle makes minor adjustments existing prop Lets examine what happens 20inch-pitch prop computed above Assume have cut inch out center prop spars leave 15 inches diameter Using tissue sockets can splice two blades together following chart compares blade angle vs diameter data previously shown pitch resulting four kinds change prop blade can rotated lower angle higher angle can shortened also can shortened rotated higher angle computations show results rotating blade five degrees five degrees less shortening 16-inch diameter 15 inches blade one-halfinch shorter right column combines effect shortening blade increasing angle five degrees case computation begins angle blade element shown original chart computed result same segment shown change condition right CL AerobaticslMcMillan Continued page 123 Tech Tips Last year discussed sealing control surface hinge lines extremely effective trimming tool Because chances good will help no question should try new planes Although doesnt help planes wont know until give go benefit prevention funnies Windy Urtnowski calls outboard wing rebuilt Caudron popped up top inside outside rounds First sealed CL Speed/Lee Continued paqe 125 needle setting wont change Different pins required different props stored hole end block kept threaded brass plug terrific accessory ease prop modification increase flight repeatability Another interesting thing Nats Bill Wisniewskis 21 K&B engine used grandson Mike 21 Sport Speed Bill used sleeve piston Sportster 20 drum rotor space between hinges wing still behaved same desperation ran continuous strip root tip funny gone best could figure out hinge cutouts tip bleeding air small things can real killers main reason brought up pass information found unlikely place using 3Ms plastic tape satisfactory adhesive effective because low tack however since tape bit thick controls somewhat stiff led search something better Continued page 165 rear end used marine version engine built ball-bearing crankshaft crankcase trouble conrodthe bronze bushing kept going outso pressed high-silicon aluminum bushing worked great engine ran very well K&B engines now have clearance conrods much 005 being used lower end engine performance reliability better ever See Nats photos couple new engines Wiley 40 Jett 40 Ill try get performance information future column h itch after change DiaBlade Angle 2 726 4 579 6 467 8 385 10 325 12 279 14 244 16 217 152 166 168 166 163 159 155 150 266 246 239 238 241 244 248 253 15 dia 149 175 183 187 190 191 192 214 215 219 224 229 234 239 Figure 3 graphs pitch distribution rotated blades comparison standard 20-inch helical blade using variable pitch props think about widely pitch varies over range allow angle change may profit planning what pitch block build blades use high-pitch block equal upper limit setting lower settings will have center blade doing work efficient Im sure anyone knows sure interesting think about Model Aviation 4