Control iIM Racing Bill Lee OVER THE LAST 10 years perform ance level racing aircraft has improved dramatically Yet equipment use now quite similar cases what come performance increase As example 1972 last Chicago Nats qualified Goodyear racer about 328 fastest qualifier days Good year running the 17s quite good 16s super Engines use predominantly Supertigre G-15 few Rossi iSs showing up An Aldrich Rossi plane Chicago running 60% nitro fuel nylon 7-6 prop cut 6 diameter K&B plug Over years speeds have jumped 1979 last year 52 ft 012 lines used lot Goodyears running mid-14s some reports high 13s What contributing factors very significant speed increase First introduction GloBee plugs quite impact plug very much durable subjected rigors CL racing other type plug able change head shapes use com pression same reliably performance went up second factor realization cleaner streamlined airplanes will go through air faster same amount power trend has get rid elements planes cause drag has resulted internally connected lines controls built body tank positioning completely behind engine etc third item believe significant propeller technology 1972 propeller Goodyear Tornado nylon 7-6 short later 1974 recall first Al Kellys fiberglass epoxy props started become available tried found quick -sec speed Over next few years people trying different things some success next significant prop Kellys Willoughby ver sion same Tornado nylon copy prop used airplane would let work again -sec faster original glass copy 1978 same basic Goodyear same engine 1972but better propswss reliably ninninr mid14s prop still available today Kelly still better Goodyear props around Lets talk props liule bit propeller blade fact airfoil high aspect ratio varying planform cross-section ele ment strip produces its own increment lift drag integrated blade root tip results useful forward thrust plus resistance rotation latter must overcome application power engine Because blade rotating direction velocity air meeting blade element varies widely hub tip maximum overall efficiency angle attack pitch element must adjusted produce best local lift-to-drag ratio reason propeller blade twisted make geometrical pitch approximate calculated optimum pitch point along blade Solid fixed pitched aircraft propellers carved wood machined solid forgings operate maximum efficiency specific air speed air density rotational sped engine power Departure design conditions reduces efficiency im pairs effectiveness~ quote taken directly Encyclo paedia Brittanica has key im proved performance through better props Go back re-read quote particularly last paragraph prop works maximum efficiency spec j/Fc air speed air density rota tional speed engine power Combat ship Stunter cannot singie prop works maximum efficiency time due widely varying air speed requirements events Racing Speed normally fly models near uniform speed altitude dont changing condi tions affect other events can design props work optimal efficiency majority time general horseContinued page 134 62 Model Aviation California cold wet Vic Garner Bill Lee show off Goodyear racers Merced 1978 Both Rossi-powered Bills plane won Goodyear 1979 NatIonals Bill Lee cnecKs out ma nat isacer arter neat sunny California couple years ago uaie kong ana Leonard Ascher trying todecide really cowpuncher Buckeye BJMIW&FACTURERS NAME 4 DEOClASTMM 161MIDGEST BEERCAT69954599 162ASTROPLITE 896I189957699 163 SUPER Mc84TEREY59953899 164 U39952799 165 FOURNIER59953899 166 ELEC FLIGHT SYSTEM69955299 167BED 3 GEAR PNELRIATIC RETRACTS59956799 168 AM PNEUMATIC RETRACTS62584699 169COUER1TE BALSARITE I2 PT358258 178 IMES 12 PT345245 171C 8 ASSOC GUFORA PROP ADORTOR19951499 172 14 SCALE TAIL lO-L19951499 173FLITECRBET CORDINAL SF083139959899 174FLITORA 72 N4Z CRYSTAL SET1195949 175 TRAINER CORD895699 176OR LINE 28 FLOATS24951799 177 R 98TH57954299 17819 PRODILTS I1D FUEL P1WROT 995699 179DREMEL BELT WIDER184956499 188 2 DELUX 9030 SNGP114956995 181 1 MOTOTOGI. KIT84954999 182TOFFLITE FORRIKOTE 4X1242882749 183NIGI4OINT PRECISION BALANCEF23951999 184PICA WIEB NEt KIT64955899 185BTUPFLITE P47 CORSAIR BEORCHT1899561998 186STRO8EF-LIONT STROBE ASSEURlB SB858 187 ASSEM817881358 188FIREBALL PLUGS 813 838 LORO1186499 189 REG S28 LONO1186499 198TOFFLITE 28 PROPS MILT UP 218882135B 191 ROPS MALT OF 2988212B8 192NEAOLSE9 PLUG CONNECTOR295195 193S4CTO 811 ALADES 12 P8K199149 BY REOLEST IE ORE EXTEORING TOR SALE ON MONOKOTE 8 FIKOTE P8011 LAST MONTA CNECI 98 IN JLLV 1586E USE 3 DIGIT COI8UTER I4NER I*EN PLACING BA CAMER SENG ALL ORDERS E INEOJIRES TOI ** IWELIBNIIA *** PO BOX 178 ROCKAUNY PORK NY 11694 ALL PRICES SUBJECT TO 018845E OFFER GOOD TIL 15TH RE ThIS EXTH IBBESS CLI84ENT SUPPLIES ORE E81*RJSTED 181 SPECIALSLIST FREE WITH ORDERS OR GENE SAME 88 8188 REFUNEABLE WITH ORDER FREE WITH ALL ORDERS FREE ORDERING IWORtIATION SORRY 98 COD ALL PRICES INCLUDE 55 CASH DISCOUNT MIX NET ORDER 818 MASTERGISA ACCEPTED BUr YOU FIJST ADO 511 BACK TO TOTAL INCLL8E CORD B 88 EXPIRATION DATE INTERBANK 8 8 SIGNATURE OF CORD ELDER SHIPPINGHBAOLINO 18883588 980 388 35817888 ADO 688 CIDER 7888 980 911 84 OF 1858 BAD 25 LBS * OUERSIZE BOX ADO EXTRA 8588 OUT OF CONT US ADO 1511 OF TOTAL FOR SHIPPING ALL MONIES MUST BE IN US CURRENCY ALL SALES ORE FINAL ALLC8 TIME FOR PERSONAL CNECK TO CLEAR NY RESIDENTS MUST ADD APPLICORLE SALES TPO INCLUGE SAGE FUR ALL INQUIRES SPECIFY SIZE COLOR AND TYPE 18EREUER REGUIRED ND PREPARED ON MNY 15 1991 Dont forget about Combat Nationals Thursday Flying wilt begin after Junior Senior Combat entry fee $300 excess monies go Team Fund Rich Lopez Steve Hills will run event promise some great prizes Great chance build fly Cheap Imitation Flying Lines plans buy either VoA Viper Bear Model Products exotic Monoboom Hoffelt Group AeroSport Maybe Gene will lend another model can fly too FAI Team Trials coming up midSeptember Nashville Paul Smith sent along note clarify reasons trials Nationals Id mentioned last column real disadvantage having some place other Nats expense spelled $400 air travel West Coast people As Paul said its worth $400 live San Diego year round organizational committee team trials has really put lot effort thought program has come up best possible solution AMA President John Grigg Micheline Madison AMA HQ Administrator FAI programs scheduled come trials year another first Supertigre 15 FAI Combat should have local hobby shop about month time read John Gladfelter reports World Engines motor will offer everything could ask FAI engine has lots power good mileage consistent needle settings good parts avail ability mention few definite horse power race going FAI what Foxes producing well over what Duke ever dreamed possible design Rossi clan sometimes running much nitro would run Goodyear days G-15 nylon prop long gone Some real horsepower exotic props along greater variety models will seen 1981 Bladder Grabber triple-elimination Fast Combat contest will held Seattle over 4th July weekend super-extravaganza will feature over $3800 Carver Corporation stereo equipment prizes Howard Rush told lights house dim cranks up power stereo won last time Bladder Grabber great thing about CL meets dont have invited order compete such expensive prizes newcomer like Howard would have chance winning Charlie Johnson 3716 Ingraham St San Diego CA 92109 CL Racing/Lee Continued page 62 power output air density dont change very much day next two variables have left air speed rotational speed ie engine rpm HENDERTOON 1- flGUI&E UAgEg CAL6 COi1OVLiJ WOUtt 13E ~AL C4A/uLE~3GE 134 Model Aviation hobby shop owners know good thing see going order bunch MODELMANIAstores RANDYS UNIFLOW STUNT TANKS P ROF IL E * COM B AT* R AT* WIDE & NARROW WEDGE 2-- 6 oz Capacities Standard Yeflt aYailable CUSTOM BLEND FUEL 5 -- 40% Nitro Send 25Cents specs CAROLINA- TAFFINDER 8345 Delhi Road Charleston Hgts SC 29405 Lets define few terms Effective Pitch EP propeller distance model moves forward revolution prop easily calculated value can measure airspeed model engine rpm model flying air speed easy measure using stopwatch engine rpm air isnt easy audio tach being practical way Unfortunately audio tachs readily available esti mates needed rule thumb have used Rat Goodyear Slow Rat will unload about 2000 rpm between ground air ground measurement can used An audio tach still way go can find EP calculated using formula S 1056 EPR S airspeed measured mph R engine rpm EP distance plane moves inches per revolution what would measure stations prop believed prop flying exactly 00 degrees respect air plane moves forward prop turns prop working 100% efficiency rpm air speed have measured pitch measured prop should equal EP nature kind Props need work some angle attack job selection angle attack key better props racing An aeronautical engineer friend told day Clark Y airfoil has its maximum lift/drag ratio operating angle attack relative path through air around 20 degrees looked shape blade airfoil usually ended up carving decided justwhat doctor ordered didnt have formulas necessary convert desire inches pitch sat down figured out S speed mph R Engine rpm S1056 EP ctive Pitch t Q Radius inches station prop Angle blade -1 EP thena inradians tan I 2 irQi red angle attack degrees P es pitch Q 2 irR tan C 180 formulas will let calculate inches pitch required particular angle attack value Q dependent measuring prop relation center Most us probably using Prather pitch gauge certainly need some sort gauge work props values Q can calculated follows Let Prather station number Q 3715 Q resulting inches formulas may look complex can programmed quite easily hand calcu lator have access some sort computer program calculating pitch function angle attack can easily written have FORTRAN program calcu late numbers anyone interested drop line will send copy SASE efforts over past year using approach pitching props have constant angle attack hub tip has yielded some very positive results revised Rat prop full -sec faster same engine/fuel/plug using stock Kelly- Gillott S-S same prop also helped Slow Rat sec although later work yielded better props Slow date havent able achieve much improvement Goodyears compared Willoughby has very good pitch distribution begin W R Lee 3522 Tamarisk Lane Missouri City TX 77459 Cb Es PATTERN AND 4 HIGH SPEED PROPELLERS IRSCREW CUSTOM HIGH PERFORMANCE MAPLE PROPELLERS Propeller designed using symmetrical profile Individually precision hand balanced Accurale airfoil pitch Only high Quality straight grain Eastern Maple used 8% X 6% FORMULA 1 10X6 0 0 11X711X7/2 iixa CUSTOM DESIGN UPON REOUEST OIRECT SALES miv PRODUCTS 5634 CRYSTAL COURT SANTA ROSA CA 95004 PHONE TOY SARUSSA *40 $100 p 04 0 postag hanSq CA UPS ADO 0% TAO Towson Ave iitas 72901 USA edge power e nitro formulated fuels Introducing Coverites First Kit Fabulous Dealer write Coerite 420 Babylon Rd Ilorsham PA 19044 IN STOCK POR IMMEDIATE SHIPMENT New SUPER QUADRA IGHELLA FLYWHEEL$10695 QUADRA MARINE engine$12495 QUADRA REPAIR$1000 plus psrts KIORITZ engine 244 co in$19995 Jim Messer ERCOUPEPLANS $2195 KIT $21995 Jim MesserTOMAHAWKPLANS $2195 KIT$23995 BALSA BASSWOOD sizesl40% OFF Concept FLEET KIT -$17995 PG Cowl $1995 P & W RADIAL ENGINES set 5 Fleet $2995 VICKERS LEWIS MACHINE GUN KITS $1495 10 dia COVERED WHEELS USA Pup$2695 PLANS SUPER STEARMAN Godfrey $2495 STARDUSTER TOO /o Brisi hells $2995 WACO HKS-7&GREAT LAKESRosenstock $2495 VOLKSPLANE /g lChicken Charlie $2195 FLY BABY /9$iS95SE-s /9 Rausch$249S COCKPIT KITS Stearman Fleet F4U-1$ia00 Ercoupe $1500 Tomahawk $2150 Citabria $2495 J-3 Cub $1550 Me-i 09 $1950 Spitfire $219S FIBERGLASS ARROW SHAFTS 5116x32 1g 6/51000 24-Hour Se~ce. Add $250 postage Send Bank Check Money Order JIM MESSERS QUALITY MODEL PRODUCTS 106 Valley View DrAllegany NY 14706 September1981 135
Edition: Model Aviation - 1981/09
Page Numbers: 62, 134, 135
Control iIM Racing Bill Lee OVER THE LAST 10 years perform ance level racing aircraft has improved dramatically Yet equipment use now quite similar cases what come performance increase As example 1972 last Chicago Nats qualified Goodyear racer about 328 fastest qualifier days Good year running the 17s quite good 16s super Engines use predominantly Supertigre G-15 few Rossi iSs showing up An Aldrich Rossi plane Chicago running 60% nitro fuel nylon 7-6 prop cut 6 diameter K&B plug Over years speeds have jumped 1979 last year 52 ft 012 lines used lot Goodyears running mid-14s some reports high 13s What contributing factors very significant speed increase First introduction GloBee plugs quite impact plug very much durable subjected rigors CL racing other type plug able change head shapes use com pression same reliably performance went up second factor realization cleaner streamlined airplanes will go through air faster same amount power trend has get rid elements planes cause drag has resulted internally connected lines controls built body tank positioning completely behind engine etc third item believe significant propeller technology 1972 propeller Goodyear Tornado nylon 7-6 short later 1974 recall first Al Kellys fiberglass epoxy props started become available tried found quick -sec speed Over next few years people trying different things some success next significant prop Kellys Willoughby ver sion same Tornado nylon copy prop used airplane would let work again -sec faster original glass copy 1978 same basic Goodyear same engine 1972but better propswss reliably ninninr mid14s prop still available today Kelly still better Goodyear props around Lets talk props liule bit propeller blade fact airfoil high aspect ratio varying planform cross-section ele ment strip produces its own increment lift drag integrated blade root tip results useful forward thrust plus resistance rotation latter must overcome application power engine Because blade rotating direction velocity air meeting blade element varies widely hub tip maximum overall efficiency angle attack pitch element must adjusted produce best local lift-to-drag ratio reason propeller blade twisted make geometrical pitch approximate calculated optimum pitch point along blade Solid fixed pitched aircraft propellers carved wood machined solid forgings operate maximum efficiency specific air speed air density rotational sped engine power Departure design conditions reduces efficiency im pairs effectiveness~ quote taken directly Encyclo paedia Brittanica has key im proved performance through better props Go back re-read quote particularly last paragraph prop works maximum efficiency spec j/Fc air speed air density rota tional speed engine power Combat ship Stunter cannot singie prop works maximum efficiency time due widely varying air speed requirements events Racing Speed normally fly models near uniform speed altitude dont changing condi tions affect other events can design props work optimal efficiency majority time general horseContinued page 134 62 Model Aviation California cold wet Vic Garner Bill Lee show off Goodyear racers Merced 1978 Both Rossi-powered Bills plane won Goodyear 1979 NatIonals Bill Lee cnecKs out ma nat isacer arter neat sunny California couple years ago uaie kong ana Leonard Ascher trying todecide really cowpuncher Buckeye BJMIW&FACTURERS NAME 4 DEOClASTMM 161MIDGEST BEERCAT69954599 162ASTROPLITE 896I189957699 163 SUPER Mc84TEREY59953899 164 U39952799 165 FOURNIER59953899 166 ELEC FLIGHT SYSTEM69955299 167BED 3 GEAR PNELRIATIC RETRACTS59956799 168 AM PNEUMATIC RETRACTS62584699 169COUER1TE BALSARITE I2 PT358258 178 IMES 12 PT345245 171C 8 ASSOC GUFORA PROP ADORTOR19951499 172 14 SCALE TAIL lO-L19951499 173FLITECRBET CORDINAL SF083139959899 174FLITORA 72 N4Z CRYSTAL SET1195949 175 TRAINER CORD895699 176OR LINE 28 FLOATS24951799 177 R 98TH57954299 17819 PRODILTS I1D FUEL P1WROT 995699 179DREMEL BELT WIDER184956499 188 2 DELUX 9030 SNGP114956995 181 1 MOTOTOGI. KIT84954999 182TOFFLITE FORRIKOTE 4X1242882749 183NIGI4OINT PRECISION BALANCEF23951999 184PICA WIEB NEt KIT64955899 185BTUPFLITE P47 CORSAIR BEORCHT1899561998 186STRO8EF-LIONT STROBE ASSEURlB SB858 187 ASSEM817881358 188FIREBALL PLUGS 813 838 LORO1186499 189 REG S28 LONO1186499 198TOFFLITE 28 PROPS MILT UP 218882135B 191 ROPS MALT OF 2988212B8 192NEAOLSE9 PLUG CONNECTOR295195 193S4CTO 811 ALADES 12 P8K199149 BY REOLEST IE ORE EXTEORING TOR SALE ON MONOKOTE 8 FIKOTE P8011 LAST MONTA CNECI 98 IN JLLV 1586E USE 3 DIGIT COI8UTER I4NER I*EN PLACING BA CAMER SENG ALL ORDERS E INEOJIRES TOI ** IWELIBNIIA *** PO BOX 178 ROCKAUNY PORK NY 11694 ALL PRICES SUBJECT TO 018845E OFFER GOOD TIL 15TH RE ThIS EXTH IBBESS CLI84ENT SUPPLIES ORE E81*RJSTED 181 SPECIALSLIST FREE WITH ORDERS OR GENE SAME 88 8188 REFUNEABLE WITH ORDER FREE WITH ALL ORDERS FREE ORDERING IWORtIATION SORRY 98 COD ALL PRICES INCLUDE 55 CASH DISCOUNT MIX NET ORDER 818 MASTERGISA ACCEPTED BUr YOU FIJST ADO 511 BACK TO TOTAL INCLL8E CORD B 88 EXPIRATION DATE INTERBANK 8 8 SIGNATURE OF CORD ELDER SHIPPINGHBAOLINO 18883588 980 388 35817888 ADO 688 CIDER 7888 980 911 84 OF 1858 BAD 25 LBS * OUERSIZE BOX ADO EXTRA 8588 OUT OF CONT US ADO 1511 OF TOTAL FOR SHIPPING ALL MONIES MUST BE IN US CURRENCY ALL SALES ORE FINAL ALLC8 TIME FOR PERSONAL CNECK TO CLEAR NY RESIDENTS MUST ADD APPLICORLE SALES TPO INCLUGE SAGE FUR ALL INQUIRES SPECIFY SIZE COLOR AND TYPE 18EREUER REGUIRED ND PREPARED ON MNY 15 1991 Dont forget about Combat Nationals Thursday Flying wilt begin after Junior Senior Combat entry fee $300 excess monies go Team Fund Rich Lopez Steve Hills will run event promise some great prizes Great chance build fly Cheap Imitation Flying Lines plans buy either VoA Viper Bear Model Products exotic Monoboom Hoffelt Group AeroSport Maybe Gene will lend another model can fly too FAI Team Trials coming up midSeptember Nashville Paul Smith sent along note clarify reasons trials Nationals Id mentioned last column real disadvantage having some place other Nats expense spelled $400 air travel West Coast people As Paul said its worth $400 live San Diego year round organizational committee team trials has really put lot effort thought program has come up best possible solution AMA President John Grigg Micheline Madison AMA HQ Administrator FAI programs scheduled come trials year another first Supertigre 15 FAI Combat should have local hobby shop about month time read John Gladfelter reports World Engines motor will offer everything could ask FAI engine has lots power good mileage consistent needle settings good parts avail ability mention few definite horse power race going FAI what Foxes producing well over what Duke ever dreamed possible design Rossi clan sometimes running much nitro would run Goodyear days G-15 nylon prop long gone Some real horsepower exotic props along greater variety models will seen 1981 Bladder Grabber triple-elimination Fast Combat contest will held Seattle over 4th July weekend super-extravaganza will feature over $3800 Carver Corporation stereo equipment prizes Howard Rush told lights house dim cranks up power stereo won last time Bladder Grabber great thing about CL meets dont have invited order compete such expensive prizes newcomer like Howard would have chance winning Charlie Johnson 3716 Ingraham St San Diego CA 92109 CL Racing/Lee Continued page 62 power output air density dont change very much day next two variables have left air speed rotational speed ie engine rpm HENDERTOON 1- flGUI&E UAgEg CAL6 COi1OVLiJ WOUtt 13E ~AL C4A/uLE~3GE 134 Model Aviation hobby shop owners know good thing see going order bunch MODELMANIAstores RANDYS UNIFLOW STUNT TANKS P ROF IL E * COM B AT* R AT* WIDE & NARROW WEDGE 2-- 6 oz Capacities Standard Yeflt aYailable CUSTOM BLEND FUEL 5 -- 40% Nitro Send 25Cents specs CAROLINA- TAFFINDER 8345 Delhi Road Charleston Hgts SC 29405 Lets define few terms Effective Pitch EP propeller distance model moves forward revolution prop easily calculated value can measure airspeed model engine rpm model flying air speed easy measure using stopwatch engine rpm air isnt easy audio tach being practical way Unfortunately audio tachs readily available esti mates needed rule thumb have used Rat Goodyear Slow Rat will unload about 2000 rpm between ground air ground measurement can used An audio tach still way go can find EP calculated using formula S 1056 EPR S airspeed measured mph R engine rpm EP distance plane moves inches per revolution what would measure stations prop believed prop flying exactly 00 degrees respect air plane moves forward prop turns prop working 100% efficiency rpm air speed have measured pitch measured prop should equal EP nature kind Props need work some angle attack job selection angle attack key better props racing An aeronautical engineer friend told day Clark Y airfoil has its maximum lift/drag ratio operating angle attack relative path through air around 20 degrees looked shape blade airfoil usually ended up carving decided justwhat doctor ordered didnt have formulas necessary convert desire inches pitch sat down figured out S speed mph R Engine rpm S1056 EP ctive Pitch t Q Radius inches station prop Angle blade -1 EP thena inradians tan I 2 irQi red angle attack degrees P es pitch Q 2 irR tan C 180 formulas will let calculate inches pitch required particular angle attack value Q dependent measuring prop relation center Most us probably using Prather pitch gauge certainly need some sort gauge work props values Q can calculated follows Let Prather station number Q 3715 Q resulting inches formulas may look complex can programmed quite easily hand calcu lator have access some sort computer program calculating pitch function angle attack can easily written have FORTRAN program calcu late numbers anyone interested drop line will send copy SASE efforts over past year using approach pitching props have constant angle attack hub tip has yielded some very positive results revised Rat prop full -sec faster same engine/fuel/plug using stock Kelly- Gillott S-S same prop also helped Slow Rat sec although later work yielded better props Slow date havent able achieve much improvement Goodyears compared Willoughby has very good pitch distribution begin W R Lee 3522 Tamarisk Lane Missouri City TX 77459 Cb Es PATTERN AND 4 HIGH SPEED PROPELLERS IRSCREW CUSTOM HIGH PERFORMANCE MAPLE PROPELLERS Propeller designed using symmetrical profile Individually precision hand balanced Accurale airfoil pitch Only high Quality straight grain Eastern Maple used 8% X 6% FORMULA 1 10X6 0 0 11X711X7/2 iixa CUSTOM DESIGN UPON REOUEST OIRECT SALES miv PRODUCTS 5634 CRYSTAL COURT SANTA ROSA CA 95004 PHONE TOY SARUSSA *40 $100 p 04 0 postag hanSq CA UPS ADO 0% TAO Towson Ave iitas 72901 USA edge power e nitro formulated fuels Introducing Coverites First Kit Fabulous Dealer write Coerite 420 Babylon Rd Ilorsham PA 19044 IN STOCK POR IMMEDIATE SHIPMENT New SUPER QUADRA IGHELLA FLYWHEEL$10695 QUADRA MARINE engine$12495 QUADRA REPAIR$1000 plus psrts KIORITZ engine 244 co in$19995 Jim Messer ERCOUPEPLANS $2195 KIT $21995 Jim MesserTOMAHAWKPLANS $2195 KIT$23995 BALSA BASSWOOD sizesl40% OFF Concept FLEET KIT -$17995 PG Cowl $1995 P & W RADIAL ENGINES set 5 Fleet $2995 VICKERS LEWIS MACHINE GUN KITS $1495 10 dia COVERED WHEELS USA Pup$2695 PLANS SUPER STEARMAN Godfrey $2495 STARDUSTER TOO /o Brisi hells $2995 WACO HKS-7&GREAT LAKESRosenstock $2495 VOLKSPLANE /g lChicken Charlie $2195 FLY BABY /9$iS95SE-s /9 Rausch$249S COCKPIT KITS Stearman Fleet F4U-1$ia00 Ercoupe $1500 Tomahawk $2150 Citabria $2495 J-3 Cub $1550 Me-i 09 $1950 Spitfire $219S FIBERGLASS ARROW SHAFTS 5116x32 1g 6/51000 24-Hour Se~ce. Add $250 postage Send Bank Check Money Order JIM MESSERS QUALITY MODEL PRODUCTS 106 Valley View DrAllegany NY 14706 September1981 135
Edition: Model Aviation - 1981/09
Page Numbers: 62, 134, 135
Control iIM Racing Bill Lee OVER THE LAST 10 years perform ance level racing aircraft has improved dramatically Yet equipment use now quite similar cases what come performance increase As example 1972 last Chicago Nats qualified Goodyear racer about 328 fastest qualifier days Good year running the 17s quite good 16s super Engines use predominantly Supertigre G-15 few Rossi iSs showing up An Aldrich Rossi plane Chicago running 60% nitro fuel nylon 7-6 prop cut 6 diameter K&B plug Over years speeds have jumped 1979 last year 52 ft 012 lines used lot Goodyears running mid-14s some reports high 13s What contributing factors very significant speed increase First introduction GloBee plugs quite impact plug very much durable subjected rigors CL racing other type plug able change head shapes use com pression same reliably performance went up second factor realization cleaner streamlined airplanes will go through air faster same amount power trend has get rid elements planes cause drag has resulted internally connected lines controls built body tank positioning completely behind engine etc third item believe significant propeller technology 1972 propeller Goodyear Tornado nylon 7-6 short later 1974 recall first Al Kellys fiberglass epoxy props started become available tried found quick -sec speed Over next few years people trying different things some success next significant prop Kellys Willoughby ver sion same Tornado nylon copy prop used airplane would let work again -sec faster original glass copy 1978 same basic Goodyear same engine 1972but better propswss reliably ninninr mid14s prop still available today Kelly still better Goodyear props around Lets talk props liule bit propeller blade fact airfoil high aspect ratio varying planform cross-section ele ment strip produces its own increment lift drag integrated blade root tip results useful forward thrust plus resistance rotation latter must overcome application power engine Because blade rotating direction velocity air meeting blade element varies widely hub tip maximum overall efficiency angle attack pitch element must adjusted produce best local lift-to-drag ratio reason propeller blade twisted make geometrical pitch approximate calculated optimum pitch point along blade Solid fixed pitched aircraft propellers carved wood machined solid forgings operate maximum efficiency specific air speed air density rotational sped engine power Departure design conditions reduces efficiency im pairs effectiveness~ quote taken directly Encyclo paedia Brittanica has key im proved performance through better props Go back re-read quote particularly last paragraph prop works maximum efficiency spec j/Fc air speed air density rota tional speed engine power Combat ship Stunter cannot singie prop works maximum efficiency time due widely varying air speed requirements events Racing Speed normally fly models near uniform speed altitude dont changing condi tions affect other events can design props work optimal efficiency majority time general horseContinued page 134 62 Model Aviation California cold wet Vic Garner Bill Lee show off Goodyear racers Merced 1978 Both Rossi-powered Bills plane won Goodyear 1979 NatIonals Bill Lee cnecKs out ma nat isacer arter neat sunny California couple years ago uaie kong ana Leonard Ascher trying todecide really cowpuncher Buckeye BJMIW&FACTURERS NAME 4 DEOClASTMM 161MIDGEST BEERCAT69954599 162ASTROPLITE 896I189957699 163 SUPER Mc84TEREY59953899 164 U39952799 165 FOURNIER59953899 166 ELEC FLIGHT SYSTEM69955299 167BED 3 GEAR PNELRIATIC RETRACTS59956799 168 AM PNEUMATIC RETRACTS62584699 169COUER1TE BALSARITE I2 PT358258 178 IMES 12 PT345245 171C 8 ASSOC GUFORA PROP ADORTOR19951499 172 14 SCALE TAIL lO-L19951499 173FLITECRBET CORDINAL SF083139959899 174FLITORA 72 N4Z CRYSTAL SET1195949 175 TRAINER CORD895699 176OR LINE 28 FLOATS24951799 177 R 98TH57954299 17819 PRODILTS I1D FUEL P1WROT 995699 179DREMEL BELT WIDER184956499 188 2 DELUX 9030 SNGP114956995 181 1 MOTOTOGI. KIT84954999 182TOFFLITE FORRIKOTE 4X1242882749 183NIGI4OINT PRECISION BALANCEF23951999 184PICA WIEB NEt KIT64955899 185BTUPFLITE P47 CORSAIR BEORCHT1899561998 186STRO8EF-LIONT STROBE ASSEURlB SB858 187 ASSEM817881358 188FIREBALL PLUGS 813 838 LORO1186499 189 REG S28 LONO1186499 198TOFFLITE 28 PROPS MILT UP 218882135B 191 ROPS MALT OF 2988212B8 192NEAOLSE9 PLUG CONNECTOR295195 193S4CTO 811 ALADES 12 P8K199149 BY REOLEST IE ORE EXTEORING TOR SALE ON MONOKOTE 8 FIKOTE P8011 LAST MONTA CNECI 98 IN JLLV 1586E USE 3 DIGIT COI8UTER I4NER I*EN PLACING BA CAMER SENG ALL ORDERS E INEOJIRES TOI ** IWELIBNIIA *** PO BOX 178 ROCKAUNY PORK NY 11694 ALL PRICES SUBJECT TO 018845E OFFER GOOD TIL 15TH RE ThIS EXTH IBBESS CLI84ENT SUPPLIES ORE E81*RJSTED 181 SPECIALSLIST FREE WITH ORDERS OR GENE SAME 88 8188 REFUNEABLE WITH ORDER FREE WITH ALL ORDERS FREE ORDERING IWORtIATION SORRY 98 COD ALL PRICES INCLUDE 55 CASH DISCOUNT MIX NET ORDER 818 MASTERGISA ACCEPTED BUr YOU FIJST ADO 511 BACK TO TOTAL INCLL8E CORD B 88 EXPIRATION DATE INTERBANK 8 8 SIGNATURE OF CORD ELDER SHIPPINGHBAOLINO 18883588 980 388 35817888 ADO 688 CIDER 7888 980 911 84 OF 1858 BAD 25 LBS * OUERSIZE BOX ADO EXTRA 8588 OUT OF CONT US ADO 1511 OF TOTAL FOR SHIPPING ALL MONIES MUST BE IN US CURRENCY ALL SALES ORE FINAL ALLC8 TIME FOR PERSONAL CNECK TO CLEAR NY RESIDENTS MUST ADD APPLICORLE SALES TPO INCLUGE SAGE FUR ALL INQUIRES SPECIFY SIZE COLOR AND TYPE 18EREUER REGUIRED ND PREPARED ON MNY 15 1991 Dont forget about Combat Nationals Thursday Flying wilt begin after Junior Senior Combat entry fee $300 excess monies go Team Fund Rich Lopez Steve Hills will run event promise some great prizes Great chance build fly Cheap Imitation Flying Lines plans buy either VoA Viper Bear Model Products exotic Monoboom Hoffelt Group AeroSport Maybe Gene will lend another model can fly too FAI Team Trials coming up midSeptember Nashville Paul Smith sent along note clarify reasons trials Nationals Id mentioned last column real disadvantage having some place other Nats expense spelled $400 air travel West Coast people As Paul said its worth $400 live San Diego year round organizational committee team trials has really put lot effort thought program has come up best possible solution AMA President John Grigg Micheline Madison AMA HQ Administrator FAI programs scheduled come trials year another first Supertigre 15 FAI Combat should have local hobby shop about month time read John Gladfelter reports World Engines motor will offer everything could ask FAI engine has lots power good mileage consistent needle settings good parts avail ability mention few definite horse power race going FAI what Foxes producing well over what Duke ever dreamed possible design Rossi clan sometimes running much nitro would run Goodyear days G-15 nylon prop long gone Some real horsepower exotic props along greater variety models will seen 1981 Bladder Grabber triple-elimination Fast Combat contest will held Seattle over 4th July weekend super-extravaganza will feature over $3800 Carver Corporation stereo equipment prizes Howard Rush told lights house dim cranks up power stereo won last time Bladder Grabber great thing about CL meets dont have invited order compete such expensive prizes newcomer like Howard would have chance winning Charlie Johnson 3716 Ingraham St San Diego CA 92109 CL Racing/Lee Continued page 62 power output air density dont change very much day next two variables have left air speed rotational speed ie engine rpm HENDERTOON 1- flGUI&E UAgEg CAL6 COi1OVLiJ WOUtt 13E ~AL C4A/uLE~3GE 134 Model Aviation hobby shop owners know good thing see going order bunch MODELMANIAstores RANDYS UNIFLOW STUNT TANKS P ROF IL E * COM B AT* R AT* WIDE & NARROW WEDGE 2-- 6 oz Capacities Standard Yeflt aYailable CUSTOM BLEND FUEL 5 -- 40% Nitro Send 25Cents specs CAROLINA- TAFFINDER 8345 Delhi Road Charleston Hgts SC 29405 Lets define few terms Effective Pitch EP propeller distance model moves forward revolution prop easily calculated value can measure airspeed model engine rpm model flying air speed easy measure using stopwatch engine rpm air isnt easy audio tach being practical way Unfortunately audio tachs readily available esti mates needed rule thumb have used Rat Goodyear Slow Rat will unload about 2000 rpm between ground air ground measurement can used An audio tach still way go can find EP calculated using formula S 1056 EPR S airspeed measured mph R engine rpm EP distance plane moves inches per revolution what would measure stations prop believed prop flying exactly 00 degrees respect air plane moves forward prop turns prop working 100% efficiency rpm air speed have measured pitch measured prop should equal EP nature kind Props need work some angle attack job selection angle attack key better props racing An aeronautical engineer friend told day Clark Y airfoil has its maximum lift/drag ratio operating angle attack relative path through air around 20 degrees looked shape blade airfoil usually ended up carving decided justwhat doctor ordered didnt have formulas necessary convert desire inches pitch sat down figured out S speed mph R Engine rpm S1056 EP ctive Pitch t Q Radius inches station prop Angle blade -1 EP thena inradians tan I 2 irQi red angle attack degrees P es pitch Q 2 irR tan C 180 formulas will let calculate inches pitch required particular angle attack value Q dependent measuring prop relation center Most us probably using Prather pitch gauge certainly need some sort gauge work props values Q can calculated follows Let Prather station number Q 3715 Q resulting inches formulas may look complex can programmed quite easily hand calcu lator have access some sort computer program calculating pitch function angle attack can easily written have FORTRAN program calcu late numbers anyone interested drop line will send copy SASE efforts over past year using approach pitching props have constant angle attack hub tip has yielded some very positive results revised Rat prop full -sec faster same engine/fuel/plug using stock Kelly- Gillott S-S same prop also helped Slow Rat sec although later work yielded better props Slow date havent able achieve much improvement Goodyears compared Willoughby has very good pitch distribution begin W R Lee 3522 Tamarisk Lane Missouri City TX 77459 Cb Es PATTERN AND 4 HIGH SPEED PROPELLERS IRSCREW CUSTOM HIGH PERFORMANCE MAPLE PROPELLERS Propeller designed using symmetrical profile Individually precision hand balanced Accurale airfoil pitch Only high Quality straight grain Eastern Maple used 8% X 6% FORMULA 1 10X6 0 0 11X711X7/2 iixa CUSTOM DESIGN UPON REOUEST OIRECT SALES miv PRODUCTS 5634 CRYSTAL COURT SANTA ROSA CA 95004 PHONE TOY SARUSSA *40 $100 p 04 0 postag hanSq CA UPS ADO 0% TAO Towson Ave iitas 72901 USA edge power e nitro formulated fuels Introducing Coverites First Kit Fabulous Dealer write Coerite 420 Babylon Rd Ilorsham PA 19044 IN STOCK POR IMMEDIATE SHIPMENT New SUPER QUADRA IGHELLA FLYWHEEL$10695 QUADRA MARINE engine$12495 QUADRA REPAIR$1000 plus psrts KIORITZ engine 244 co in$19995 Jim Messer ERCOUPEPLANS $2195 KIT $21995 Jim MesserTOMAHAWKPLANS $2195 KIT$23995 BALSA BASSWOOD sizesl40% OFF Concept FLEET KIT -$17995 PG Cowl $1995 P & W RADIAL ENGINES set 5 Fleet $2995 VICKERS LEWIS MACHINE GUN KITS $1495 10 dia COVERED WHEELS USA Pup$2695 PLANS SUPER STEARMAN Godfrey $2495 STARDUSTER TOO /o Brisi hells $2995 WACO HKS-7&GREAT LAKESRosenstock $2495 VOLKSPLANE /g lChicken Charlie $2195 FLY BABY /9$iS95SE-s /9 Rausch$249S COCKPIT KITS Stearman Fleet F4U-1$ia00 Ercoupe $1500 Tomahawk $2150 Citabria $2495 J-3 Cub $1550 Me-i 09 $1950 Spitfire $219S FIBERGLASS ARROW SHAFTS 5116x32 1g 6/51000 24-Hour Se~ce. Add $250 postage Send Bank Check Money Order JIM MESSERS QUALITY MODEL PRODUCTS 106 Valley View DrAllegany NY 14706 September1981 135