Radio Control SOARING Dan Pruss KEEPING UP technology Through combined efforts Jim Gray RC Soaring editor Model Airplane News Herk Stokely member Tidewater Model Soaring Society editor/contributor clubs newsletter brand new publication available called Soar Tech first edition compilation con tributions modelers includes procedure running Sailplane performance program using TI-59 pocket computer also excerpts Dieter Althams recent book model-aircraft-type airfoil sections contribution Ken Bates experimental development flying wing designs included study Al Scidmore batteries cold weather flying first issue fine effort its cost just 510 Order Herk Stokely 1504 Horseshoe Circle Virginia Beach VA 23451 News Switzerland photos month taken attending Intemational RC Soaring Flight Forum 1SF Switzerland forums have held since 1978 orig inally instituted Austrias Fridolin Fritz Das sel fame Hansruedi Schlapfer Helmut Wehren Switzerland both driving force behind Spartakus design construction techniques Over years 1SF has focal point gather showing new designs new building materials building techniques New airfoil studies have made debuts guest speakers have included Doctor Eppler him self forum full two-day session supplemented set papers similar Soar Techs format Two photos show efforts Rolf Girsberger Hans Senn Its old known fact certain airfoils turbulated somewhere near leading edge will produce lift given wing lower speeds same wing will its clean configuration Dieter Althaus covers book figures prove instance turbulated Eppler 193 does have slight edge over clean versionbut slower speeds youre F3B multi-task competition turbulatorand Althaus tests its strip 1/16-in mylar tapedoesnt yuou favors higher speed realms such Speed Distance tasks What Girsberger Seon came up blasturbulatorloosely translated first photo note hole nose fuselage hole air source funnels its air through some plumbing tubes mounted full-span wings valve fuselage piping controls airflow out wings other photo shows small holes have drilled wing down tubing turbulator air desired fuse lage valve opened air flows out wings escapes out series pin holes creating effective turbulator system works drawback enough air can scooped through nose slower speeds air gets bled off before can reach outer wing sections idea adding small air pump accumulator discussed way improve system As stated earlier forums exchange ideas secrets kept well-hidden Alps because biggest names Swiss modeling world gathered years forum offer latest Over ISO model ers attendance Peter Gerber showed newest designtwo have placed 1983 Swiss F3B team called Gamma Built best tradition clean design flawless finish Gamma features pivoting wing Rather using ail erons flaperons wing driven servo pivots about main spans wing rod Continued page 126 Experimental blasturbulator setup Swiss Sailplane Hole models nose L admits ram air internal distribution manifold ducts air out wings R fine holes wing upper surface allow blast out turbulate airatream Its effective low speeds though much work needs done fuselage-mounted servo-operated valve controls air supply Rectangular areas wing around some turbulator holes merely pieces tape used seal oft some holes tests 46 Model Aviation Helmut Wehren shows simple steps making aluminum-faced molds glass wing construction photos taken recent Swiss symposium Dan tells about column Sequence starts left Helmut getting ready crease sheet 012 aluminum GRAPHICS THE ROLLS ROYCE OF NUMBERS & LETTERS THEY STAY ON EVEN WHEN DRENCHED U WITH FUEL MICRO-THIN CAST VINYL PEEL EM OFF & STICK EM ON C@4/ERflE i L A9A gd-,tn, Rd Hnrham PA 19044 USA Send S200 refundable first purchase catalogue price list See local dealer order direct pay postage handling shipments CLARK INDUSTRIES H81 black part 1170 gray Dark green 6 parts H66 dark red 2 parts H33 Stinson green part H49 Cub yellow part H81 black part HIO white Sky type 5 5 parts RIO white part H26 light blue part H70 gray colors Hobbypoxy stock Bob Dolly Wiseher 5-221 Lapham Peak Rd. Delafield WI 53018 RC Soaring/Pruss Continued page 46 airfoil Gerbers original airfoil threeviews will appear next month Meanwhile youll get idea bird picture youre school pivots wings thats OK its small school keeping hinge lines clean has concern attempting keep wing surfaces unbroken air flows uninterrupted best hinge line flaps ailerons concave/convex joint wherein convex leading edge control surface mates convex section wing type joint nearly impossible match hand tapered wing takes real craftsman fashion straight wing other photo shows wing root another Swiss design has around since 1980the Piranha first Sailplanes seriously designed F3B using Eppler 214 airfoil beginning Piranha gave designer fits before fliers felt out advantages flapped airfoil now three years later realizing full potential airfoil plane Both electroflight version original Sailplanes doing just fine Three-views bird will also appear next month meantime wing root section shows solve hinge line problem using tape MonoKote works fine flap full span underside wing flap joint wing flap joint upper side always closed regardless flap position Note cutout wing trailing edge section leading edge shape flap makes whole action possible added feature adaptable flap root/fuselage joint note what ap pears excess material hangs fuselage side flap material Mono Kote about 3/16 inch hangs over wing position against fuse lage MonoKote overhang makes tight joint forms small fillet against fuselage As flap moves fillet just wipes fuse lage preventing air gap thereby preventing added drag picture worth thousand words next series shots should prove axiom Mold-making seems state art wing-making forums evidence Some modelers have gone through pains produce just modelsome quarter-scale variety builders arguments Once have mold its easy reproduce wing stab whatever know replace ment exact duplicate original can afford time cost such ventures Several months several hun dreds dollars have spent projects such Spartakus Dassel 800 hours Spartakus molds Enter Helmut Webren same gent engineered Spartakus molds new method wings reduces mold-making down just few hours easy steps 1 Cut have cut foam wing tail section used model 2 Put aside cores kgep beds saddles 3 Get sheet aluminumWebren uses 012and prepare bending over sharp edge first sequence photos 4 Using straight piece extruded alu minum bend sheet down gently forming defined crease second sequence photo 5 Carefully work shett back against itself using straight-edge tool making sure allow sheet flow shape crease back Third sequence photo 6 Holding sheet together squeezing creased side closed run sanding block back forth along creased edge several strokes Fourth sequence photo 7 Using two straight edges open fold sheet will separate sanded crease Next to-last sequence photo 8 final photo sequence shows upper lower wing skins will now glued wing core beds aluminum skins provide finished sur faces beds form molds until now took epoxy aforementioned hours work Reinforce foam beds angle alu minum straight wooden frames start laying up glass wings stabs Soar Tech 1SF Sounds like theyre both right track benefit us Also sounds like theres room NSS LSF interested soaring group sponsor weekend forum like ISFs right USsomething like old DC/RC Symposium Anybody interested just ready sign piece off following came mail youre ham radio fan will RC Glider Net Monday evenings Time 2330 Zulu Frequency 7240 mHz Net Control Bob Summers W8BBY 126 Model Aviation Designed R/C Combat agile little performer can fly rings around airplane youve ever owned youre looking really spirited responsive aircraft thats easier build fly Warbird esactly what need 3 Channel RIC 19 25 36Span Mixer Included $3495 OW BIRD bird big gest best has rock steady pattern performance hats amazing because will rolls straight up out sight stock K & B 40 slows down like glider landing 64 inches beautiful flying wing will make look great field Precision kit 2540 engine 7 feet rolled plans $5995 See dealer first send check money order Pacific Air 15 Skyline Drive Woodside CA 94062 Enon OH Alden Shipp WB9WAJ Quincy IL Dan Pruss 131 E Penningion Ln Plainfield IL 60544 RC Giant Scale/Beckman Continued page 49 didnt say assume will have Toledo Hobbypoxy scale colors Last June 1 got letter Bob Pettit Pettit Paint Company Inc people make Hobbypoxy wrote tell about project under way provide paint-mixing formulas help Scale modelers re produce accurate color schemes Since museumscale accuracy prime concern Giant Scale modeling other items kept pushing down list things tell about program has reported detail Scale columns various magazines will just outline What boils down Hobbypoxy has researched colors used various aircraft lets say example WW II RAF colors labs have determined exact mixture standard Hobbypoxy colors needed match show works formula Dark Green colors used upper surfaces Hurricanes Spitfires during Battle Britain 6 parts 1166 Dark Red 2 parts H33 Stinson Green part 1149 Cub Yellow part H81 Black part 1110 White Mix together mix Flat Hardener thing sure would never have thought produce shade green starting lots dark red month get another note two three color formulas So far have WW Ilor latercoiors program continues wont long before almost color need will have figured out assume writing Hobbypoxy will let find out have colors need will probably put list future Im hoping get work out colors need Sparrowhawk Super SunRay plans Super SunRay semi-scale model patterned after small biplane racer called Sorceress original Ron Mangums model incorporate several unusual features including reverse stagger inverted gull lower wing no struts kind upper wing mounted shoulder position fuselage inverted gull dihedral lower wing provides proper wing gap same time allows use very short landing gear legs unusual quite practi cal design upper wingspan 6 ft 4 14-in chord lower wing somewhat smaller fuselage over 6-ft long 5-in wide 10Y2-in deep Rons original powered Quadra flies very well dont know what weighs plans 1 would estimate 18 20 lb plans drawn Calvin Clark con sist two sheets approximately 3 ft 7 ft first impression didnt have much detail two reasons construc tion really quite simple Ron Calvin must have assumed very experienced modelers would using plans examle dowels shown leading edge wing anchors trailing edges simply note about using nylon screws hold wing no detail shown no detail engine radio installation things wont bother experienced builder could Nor~ AVIONIUS J&AcH INC ACCUETACH 1 LCITALqMoMITOR DIR~TER GE TACHof CHARto get G& Determ ne state d Makes t possIble Select idle thIiJof yoUf N9 accuratecharge5 wsafely J5 Jtd adjUStmebatter~pack nflharg scale r 100 cycle Ch~bat watChI~~ig nals dUa1ox x out bi1t pfeCI terY combo5ffl charge 5jQfl electronics ORDER YOURS NOW 79id Send check money order no 000s NorCal AVIONICS Inc PO Box 70956 yvale CA 94086California residents add 6% tax Add $300 shipping outside continental USADealer inquiries invited real stumbling blocks beginner construction really quite straightforward simple using common sport RC techniques Except spars hardwood plywood balsa lots Some substitutions cheaper materials could save lot money example -in sheet balsa fuselage sides could replaced door-skin ply backed up -in sq spruce longerons balsa formers ribs could cut foam core board dont mean criticism design just hints accomplish same thing having mortgage farm Super SunRay uncommon design very good flier wont see sitting next field plans available Ron Mangum PO Box 8244 Greensboro NC 27410 Waco UPF-7 plans UPF-7 opencockpit biplane similar contemporary PT-17 have soft spot heart aircraft because first open biplane ever flew got private ticket late Forties small field near Portsmouth VA field like era now covered houses Anyway owner field addition Aeronca Champs used training two airplanes really intrigued clipped-wing Monocoupe restoring other operational UPF-7 owner really wrapped up Monocoupe built display model complete planned color scheme traded model him check-out flying time Waco time effort well spent part Dave Richardsons UPF-7 quarter-scale plans show Quadra mount spans 86-in 733/4-in long estimated 23 lb shown plans just within comfortable capabilities Quadra first saw Daves prototype fly STARS rally 1980 Kioritz slightly larger engine allows little margin enor puts bit snap maneuvers Almost engines under 4 ci will fit nicely radial cowl plans consist three sheets approximately 3 ft 5 ft plus smaller sheet landing gear details addition well-written four-page instruction booklet questions came mind looking plans answered time finished reading booklet available Dave Rich ardson Star Route Deposit NY 13754 50cc Quadra other day got slightly latebut very welcomeChristmas present Im writing early January UPS dropped off brand new 50cc Quadra Its first ones off production line looks great havent chance run yet will soon results will next Big Bangers article Bob Beckman 8248 Holly Grove Ct Manassas VA 22110 RC Pylon Racing/Hager Continued page 52 fiters have hard time getting engine last contest let alone whole season FAI engine possible have engine last whole Racing season started Racing glow plugs 29 39 Now some over $2 Formula use plug per flight lucky some dont last whole flight FAI competition could possibly use same plug whole weekend April 1983 127
Edition: Model Aviation - 1983/04
Page Numbers: 46, 126, 127
Radio Control SOARING Dan Pruss KEEPING UP technology Through combined efforts Jim Gray RC Soaring editor Model Airplane News Herk Stokely member Tidewater Model Soaring Society editor/contributor clubs newsletter brand new publication available called Soar Tech first edition compilation con tributions modelers includes procedure running Sailplane performance program using TI-59 pocket computer also excerpts Dieter Althams recent book model-aircraft-type airfoil sections contribution Ken Bates experimental development flying wing designs included study Al Scidmore batteries cold weather flying first issue fine effort its cost just 510 Order Herk Stokely 1504 Horseshoe Circle Virginia Beach VA 23451 News Switzerland photos month taken attending Intemational RC Soaring Flight Forum 1SF Switzerland forums have held since 1978 orig inally instituted Austrias Fridolin Fritz Das sel fame Hansruedi Schlapfer Helmut Wehren Switzerland both driving force behind Spartakus design construction techniques Over years 1SF has focal point gather showing new designs new building materials building techniques New airfoil studies have made debuts guest speakers have included Doctor Eppler him self forum full two-day session supplemented set papers similar Soar Techs format Two photos show efforts Rolf Girsberger Hans Senn Its old known fact certain airfoils turbulated somewhere near leading edge will produce lift given wing lower speeds same wing will its clean configuration Dieter Althaus covers book figures prove instance turbulated Eppler 193 does have slight edge over clean versionbut slower speeds youre F3B multi-task competition turbulatorand Althaus tests its strip 1/16-in mylar tapedoesnt yuou favors higher speed realms such Speed Distance tasks What Girsberger Seon came up blasturbulatorloosely translated first photo note hole nose fuselage hole air source funnels its air through some plumbing tubes mounted full-span wings valve fuselage piping controls airflow out wings other photo shows small holes have drilled wing down tubing turbulator air desired fuse lage valve opened air flows out wings escapes out series pin holes creating effective turbulator system works drawback enough air can scooped through nose slower speeds air gets bled off before can reach outer wing sections idea adding small air pump accumulator discussed way improve system As stated earlier forums exchange ideas secrets kept well-hidden Alps because biggest names Swiss modeling world gathered years forum offer latest Over ISO model ers attendance Peter Gerber showed newest designtwo have placed 1983 Swiss F3B team called Gamma Built best tradition clean design flawless finish Gamma features pivoting wing Rather using ail erons flaperons wing driven servo pivots about main spans wing rod Continued page 126 Experimental blasturbulator setup Swiss Sailplane Hole models nose L admits ram air internal distribution manifold ducts air out wings R fine holes wing upper surface allow blast out turbulate airatream Its effective low speeds though much work needs done fuselage-mounted servo-operated valve controls air supply Rectangular areas wing around some turbulator holes merely pieces tape used seal oft some holes tests 46 Model Aviation Helmut Wehren shows simple steps making aluminum-faced molds glass wing construction photos taken recent Swiss symposium Dan tells about column Sequence starts left Helmut getting ready crease sheet 012 aluminum GRAPHICS THE ROLLS ROYCE OF NUMBERS & LETTERS THEY STAY ON EVEN WHEN DRENCHED U WITH FUEL MICRO-THIN CAST VINYL PEEL EM OFF & STICK EM ON C@4/ERflE i L A9A gd-,tn, Rd Hnrham PA 19044 USA Send S200 refundable first purchase catalogue price list See local dealer order direct pay postage handling shipments CLARK INDUSTRIES H81 black part 1170 gray Dark green 6 parts H66 dark red 2 parts H33 Stinson green part H49 Cub yellow part H81 black part HIO white Sky type 5 5 parts RIO white part H26 light blue part H70 gray colors Hobbypoxy stock Bob Dolly Wiseher 5-221 Lapham Peak Rd. Delafield WI 53018 RC Soaring/Pruss Continued page 46 airfoil Gerbers original airfoil threeviews will appear next month Meanwhile youll get idea bird picture youre school pivots wings thats OK its small school keeping hinge lines clean has concern attempting keep wing surfaces unbroken air flows uninterrupted best hinge line flaps ailerons concave/convex joint wherein convex leading edge control surface mates convex section wing type joint nearly impossible match hand tapered wing takes real craftsman fashion straight wing other photo shows wing root another Swiss design has around since 1980the Piranha first Sailplanes seriously designed F3B using Eppler 214 airfoil beginning Piranha gave designer fits before fliers felt out advantages flapped airfoil now three years later realizing full potential airfoil plane Both electroflight version original Sailplanes doing just fine Three-views bird will also appear next month meantime wing root section shows solve hinge line problem using tape MonoKote works fine flap full span underside wing flap joint wing flap joint upper side always closed regardless flap position Note cutout wing trailing edge section leading edge shape flap makes whole action possible added feature adaptable flap root/fuselage joint note what ap pears excess material hangs fuselage side flap material Mono Kote about 3/16 inch hangs over wing position against fuse lage MonoKote overhang makes tight joint forms small fillet against fuselage As flap moves fillet just wipes fuse lage preventing air gap thereby preventing added drag picture worth thousand words next series shots should prove axiom Mold-making seems state art wing-making forums evidence Some modelers have gone through pains produce just modelsome quarter-scale variety builders arguments Once have mold its easy reproduce wing stab whatever know replace ment exact duplicate original can afford time cost such ventures Several months several hun dreds dollars have spent projects such Spartakus Dassel 800 hours Spartakus molds Enter Helmut Webren same gent engineered Spartakus molds new method wings reduces mold-making down just few hours easy steps 1 Cut have cut foam wing tail section used model 2 Put aside cores kgep beds saddles 3 Get sheet aluminumWebren uses 012and prepare bending over sharp edge first sequence photos 4 Using straight piece extruded alu minum bend sheet down gently forming defined crease second sequence photo 5 Carefully work shett back against itself using straight-edge tool making sure allow sheet flow shape crease back Third sequence photo 6 Holding sheet together squeezing creased side closed run sanding block back forth along creased edge several strokes Fourth sequence photo 7 Using two straight edges open fold sheet will separate sanded crease Next to-last sequence photo 8 final photo sequence shows upper lower wing skins will now glued wing core beds aluminum skins provide finished sur faces beds form molds until now took epoxy aforementioned hours work Reinforce foam beds angle alu minum straight wooden frames start laying up glass wings stabs Soar Tech 1SF Sounds like theyre both right track benefit us Also sounds like theres room NSS LSF interested soaring group sponsor weekend forum like ISFs right USsomething like old DC/RC Symposium Anybody interested just ready sign piece off following came mail youre ham radio fan will RC Glider Net Monday evenings Time 2330 Zulu Frequency 7240 mHz Net Control Bob Summers W8BBY 126 Model Aviation Designed R/C Combat agile little performer can fly rings around airplane youve ever owned youre looking really spirited responsive aircraft thats easier build fly Warbird esactly what need 3 Channel RIC 19 25 36Span Mixer Included $3495 OW BIRD bird big gest best has rock steady pattern performance hats amazing because will rolls straight up out sight stock K & B 40 slows down like glider landing 64 inches beautiful flying wing will make look great field Precision kit 2540 engine 7 feet rolled plans $5995 See dealer first send check money order Pacific Air 15 Skyline Drive Woodside CA 94062 Enon OH Alden Shipp WB9WAJ Quincy IL Dan Pruss 131 E Penningion Ln Plainfield IL 60544 RC Giant Scale/Beckman Continued page 49 didnt say assume will have Toledo Hobbypoxy scale colors Last June 1 got letter Bob Pettit Pettit Paint Company Inc people make Hobbypoxy wrote tell about project under way provide paint-mixing formulas help Scale modelers re produce accurate color schemes Since museumscale accuracy prime concern Giant Scale modeling other items kept pushing down list things tell about program has reported detail Scale columns various magazines will just outline What boils down Hobbypoxy has researched colors used various aircraft lets say example WW II RAF colors labs have determined exact mixture standard Hobbypoxy colors needed match show works formula Dark Green colors used upper surfaces Hurricanes Spitfires during Battle Britain 6 parts 1166 Dark Red 2 parts H33 Stinson Green part 1149 Cub Yellow part H81 Black part 1110 White Mix together mix Flat Hardener thing sure would never have thought produce shade green starting lots dark red month get another note two three color formulas So far have WW Ilor latercoiors program continues wont long before almost color need will have figured out assume writing Hobbypoxy will let find out have colors need will probably put list future Im hoping get work out colors need Sparrowhawk Super SunRay plans Super SunRay semi-scale model patterned after small biplane racer called Sorceress original Ron Mangums model incorporate several unusual features including reverse stagger inverted gull lower wing no struts kind upper wing mounted shoulder position fuselage inverted gull dihedral lower wing provides proper wing gap same time allows use very short landing gear legs unusual quite practi cal design upper wingspan 6 ft 4 14-in chord lower wing somewhat smaller fuselage over 6-ft long 5-in wide 10Y2-in deep Rons original powered Quadra flies very well dont know what weighs plans 1 would estimate 18 20 lb plans drawn Calvin Clark con sist two sheets approximately 3 ft 7 ft first impression didnt have much detail two reasons construc tion really quite simple Ron Calvin must have assumed very experienced modelers would using plans examle dowels shown leading edge wing anchors trailing edges simply note about using nylon screws hold wing no detail shown no detail engine radio installation things wont bother experienced builder could Nor~ AVIONIUS J&AcH INC ACCUETACH 1 LCITALqMoMITOR DIR~TER GE TACHof CHARto get G& Determ ne state d Makes t possIble Select idle thIiJof yoUf N9 accuratecharge5 wsafely J5 Jtd adjUStmebatter~pack nflharg scale r 100 cycle Ch~bat watChI~~ig nals dUa1ox x out bi1t pfeCI terY combo5ffl charge 5jQfl electronics ORDER YOURS NOW 79id Send check money order no 000s NorCal AVIONICS Inc PO Box 70956 yvale CA 94086California residents add 6% tax Add $300 shipping outside continental USADealer inquiries invited real stumbling blocks beginner construction really quite straightforward simple using common sport RC techniques Except spars hardwood plywood balsa lots Some substitutions cheaper materials could save lot money example -in sheet balsa fuselage sides could replaced door-skin ply backed up -in sq spruce longerons balsa formers ribs could cut foam core board dont mean criticism design just hints accomplish same thing having mortgage farm Super SunRay uncommon design very good flier wont see sitting next field plans available Ron Mangum PO Box 8244 Greensboro NC 27410 Waco UPF-7 plans UPF-7 opencockpit biplane similar contemporary PT-17 have soft spot heart aircraft because first open biplane ever flew got private ticket late Forties small field near Portsmouth VA field like era now covered houses Anyway owner field addition Aeronca Champs used training two airplanes really intrigued clipped-wing Monocoupe restoring other operational UPF-7 owner really wrapped up Monocoupe built display model complete planned color scheme traded model him check-out flying time Waco time effort well spent part Dave Richardsons UPF-7 quarter-scale plans show Quadra mount spans 86-in 733/4-in long estimated 23 lb shown plans just within comfortable capabilities Quadra first saw Daves prototype fly STARS rally 1980 Kioritz slightly larger engine allows little margin enor puts bit snap maneuvers Almost engines under 4 ci will fit nicely radial cowl plans consist three sheets approximately 3 ft 5 ft plus smaller sheet landing gear details addition well-written four-page instruction booklet questions came mind looking plans answered time finished reading booklet available Dave Rich ardson Star Route Deposit NY 13754 50cc Quadra other day got slightly latebut very welcomeChristmas present Im writing early January UPS dropped off brand new 50cc Quadra Its first ones off production line looks great havent chance run yet will soon results will next Big Bangers article Bob Beckman 8248 Holly Grove Ct Manassas VA 22110 RC Pylon Racing/Hager Continued page 52 fiters have hard time getting engine last contest let alone whole season FAI engine possible have engine last whole Racing season started Racing glow plugs 29 39 Now some over $2 Formula use plug per flight lucky some dont last whole flight FAI competition could possibly use same plug whole weekend April 1983 127
Edition: Model Aviation - 1983/04
Page Numbers: 46, 126, 127
Radio Control SOARING Dan Pruss KEEPING UP technology Through combined efforts Jim Gray RC Soaring editor Model Airplane News Herk Stokely member Tidewater Model Soaring Society editor/contributor clubs newsletter brand new publication available called Soar Tech first edition compilation con tributions modelers includes procedure running Sailplane performance program using TI-59 pocket computer also excerpts Dieter Althams recent book model-aircraft-type airfoil sections contribution Ken Bates experimental development flying wing designs included study Al Scidmore batteries cold weather flying first issue fine effort its cost just 510 Order Herk Stokely 1504 Horseshoe Circle Virginia Beach VA 23451 News Switzerland photos month taken attending Intemational RC Soaring Flight Forum 1SF Switzerland forums have held since 1978 orig inally instituted Austrias Fridolin Fritz Das sel fame Hansruedi Schlapfer Helmut Wehren Switzerland both driving force behind Spartakus design construction techniques Over years 1SF has focal point gather showing new designs new building materials building techniques New airfoil studies have made debuts guest speakers have included Doctor Eppler him self forum full two-day session supplemented set papers similar Soar Techs format Two photos show efforts Rolf Girsberger Hans Senn Its old known fact certain airfoils turbulated somewhere near leading edge will produce lift given wing lower speeds same wing will its clean configuration Dieter Althaus covers book figures prove instance turbulated Eppler 193 does have slight edge over clean versionbut slower speeds youre F3B multi-task competition turbulatorand Althaus tests its strip 1/16-in mylar tapedoesnt yuou favors higher speed realms such Speed Distance tasks What Girsberger Seon came up blasturbulatorloosely translated first photo note hole nose fuselage hole air source funnels its air through some plumbing tubes mounted full-span wings valve fuselage piping controls airflow out wings other photo shows small holes have drilled wing down tubing turbulator air desired fuse lage valve opened air flows out wings escapes out series pin holes creating effective turbulator system works drawback enough air can scooped through nose slower speeds air gets bled off before can reach outer wing sections idea adding small air pump accumulator discussed way improve system As stated earlier forums exchange ideas secrets kept well-hidden Alps because biggest names Swiss modeling world gathered years forum offer latest Over ISO model ers attendance Peter Gerber showed newest designtwo have placed 1983 Swiss F3B team called Gamma Built best tradition clean design flawless finish Gamma features pivoting wing Rather using ail erons flaperons wing driven servo pivots about main spans wing rod Continued page 126 Experimental blasturbulator setup Swiss Sailplane Hole models nose L admits ram air internal distribution manifold ducts air out wings R fine holes wing upper surface allow blast out turbulate airatream Its effective low speeds though much work needs done fuselage-mounted servo-operated valve controls air supply Rectangular areas wing around some turbulator holes merely pieces tape used seal oft some holes tests 46 Model Aviation Helmut Wehren shows simple steps making aluminum-faced molds glass wing construction photos taken recent Swiss symposium Dan tells about column Sequence starts left Helmut getting ready crease sheet 012 aluminum GRAPHICS THE ROLLS ROYCE OF NUMBERS & LETTERS THEY STAY ON EVEN WHEN DRENCHED U WITH FUEL MICRO-THIN CAST VINYL PEEL EM OFF & STICK EM ON C@4/ERflE i L A9A gd-,tn, Rd Hnrham PA 19044 USA Send S200 refundable first purchase catalogue price list See local dealer order direct pay postage handling shipments CLARK INDUSTRIES H81 black part 1170 gray Dark green 6 parts H66 dark red 2 parts H33 Stinson green part H49 Cub yellow part H81 black part HIO white Sky type 5 5 parts RIO white part H26 light blue part H70 gray colors Hobbypoxy stock Bob Dolly Wiseher 5-221 Lapham Peak Rd. Delafield WI 53018 RC Soaring/Pruss Continued page 46 airfoil Gerbers original airfoil threeviews will appear next month Meanwhile youll get idea bird picture youre school pivots wings thats OK its small school keeping hinge lines clean has concern attempting keep wing surfaces unbroken air flows uninterrupted best hinge line flaps ailerons concave/convex joint wherein convex leading edge control surface mates convex section wing type joint nearly impossible match hand tapered wing takes real craftsman fashion straight wing other photo shows wing root another Swiss design has around since 1980the Piranha first Sailplanes seriously designed F3B using Eppler 214 airfoil beginning Piranha gave designer fits before fliers felt out advantages flapped airfoil now three years later realizing full potential airfoil plane Both electroflight version original Sailplanes doing just fine Three-views bird will also appear next month meantime wing root section shows solve hinge line problem using tape MonoKote works fine flap full span underside wing flap joint wing flap joint upper side always closed regardless flap position Note cutout wing trailing edge section leading edge shape flap makes whole action possible added feature adaptable flap root/fuselage joint note what ap pears excess material hangs fuselage side flap material Mono Kote about 3/16 inch hangs over wing position against fuse lage MonoKote overhang makes tight joint forms small fillet against fuselage As flap moves fillet just wipes fuse lage preventing air gap thereby preventing added drag picture worth thousand words next series shots should prove axiom Mold-making seems state art wing-making forums evidence Some modelers have gone through pains produce just modelsome quarter-scale variety builders arguments Once have mold its easy reproduce wing stab whatever know replace ment exact duplicate original can afford time cost such ventures Several months several hun dreds dollars have spent projects such Spartakus Dassel 800 hours Spartakus molds Enter Helmut Webren same gent engineered Spartakus molds new method wings reduces mold-making down just few hours easy steps 1 Cut have cut foam wing tail section used model 2 Put aside cores kgep beds saddles 3 Get sheet aluminumWebren uses 012and prepare bending over sharp edge first sequence photos 4 Using straight piece extruded alu minum bend sheet down gently forming defined crease second sequence photo 5 Carefully work shett back against itself using straight-edge tool making sure allow sheet flow shape crease back Third sequence photo 6 Holding sheet together squeezing creased side closed run sanding block back forth along creased edge several strokes Fourth sequence photo 7 Using two straight edges open fold sheet will separate sanded crease Next to-last sequence photo 8 final photo sequence shows upper lower wing skins will now glued wing core beds aluminum skins provide finished sur faces beds form molds until now took epoxy aforementioned hours work Reinforce foam beds angle alu minum straight wooden frames start laying up glass wings stabs Soar Tech 1SF Sounds like theyre both right track benefit us Also sounds like theres room NSS LSF interested soaring group sponsor weekend forum like ISFs right USsomething like old DC/RC Symposium Anybody interested just ready sign piece off following came mail youre ham radio fan will RC Glider Net Monday evenings Time 2330 Zulu Frequency 7240 mHz Net Control Bob Summers W8BBY 126 Model Aviation Designed R/C Combat agile little performer can fly rings around airplane youve ever owned youre looking really spirited responsive aircraft thats easier build fly Warbird esactly what need 3 Channel RIC 19 25 36Span Mixer Included $3495 OW BIRD bird big gest best has rock steady pattern performance hats amazing because will rolls straight up out sight stock K & B 40 slows down like glider landing 64 inches beautiful flying wing will make look great field Precision kit 2540 engine 7 feet rolled plans $5995 See dealer first send check money order Pacific Air 15 Skyline Drive Woodside CA 94062 Enon OH Alden Shipp WB9WAJ Quincy IL Dan Pruss 131 E Penningion Ln Plainfield IL 60544 RC Giant Scale/Beckman Continued page 49 didnt say assume will have Toledo Hobbypoxy scale colors Last June 1 got letter Bob Pettit Pettit Paint Company Inc people make Hobbypoxy wrote tell about project under way provide paint-mixing formulas help Scale modelers re produce accurate color schemes Since museumscale accuracy prime concern Giant Scale modeling other items kept pushing down list things tell about program has reported detail Scale columns various magazines will just outline What boils down Hobbypoxy has researched colors used various aircraft lets say example WW II RAF colors labs have determined exact mixture standard Hobbypoxy colors needed match show works formula Dark Green colors used upper surfaces Hurricanes Spitfires during Battle Britain 6 parts 1166 Dark Red 2 parts H33 Stinson Green part 1149 Cub Yellow part H81 Black part 1110 White Mix together mix Flat Hardener thing sure would never have thought produce shade green starting lots dark red month get another note two three color formulas So far have WW Ilor latercoiors program continues wont long before almost color need will have figured out assume writing Hobbypoxy will let find out have colors need will probably put list future Im hoping get work out colors need Sparrowhawk Super SunRay plans Super SunRay semi-scale model patterned after small biplane racer called Sorceress original Ron Mangums model incorporate several unusual features including reverse stagger inverted gull lower wing no struts kind upper wing mounted shoulder position fuselage inverted gull dihedral lower wing provides proper wing gap same time allows use very short landing gear legs unusual quite practi cal design upper wingspan 6 ft 4 14-in chord lower wing somewhat smaller fuselage over 6-ft long 5-in wide 10Y2-in deep Rons original powered Quadra flies very well dont know what weighs plans 1 would estimate 18 20 lb plans drawn Calvin Clark con sist two sheets approximately 3 ft 7 ft first impression didnt have much detail two reasons construc tion really quite simple Ron Calvin must have assumed very experienced modelers would using plans examle dowels shown leading edge wing anchors trailing edges simply note about using nylon screws hold wing no detail shown no detail engine radio installation things wont bother experienced builder could Nor~ AVIONIUS J&AcH INC ACCUETACH 1 LCITALqMoMITOR DIR~TER GE TACHof CHARto get G& Determ ne state d Makes t possIble Select idle thIiJof yoUf N9 accuratecharge5 wsafely J5 Jtd adjUStmebatter~pack nflharg scale r 100 cycle Ch~bat watChI~~ig nals dUa1ox x out bi1t pfeCI terY combo5ffl charge 5jQfl electronics ORDER YOURS NOW 79id Send check money order no 000s NorCal AVIONICS Inc PO Box 70956 yvale CA 94086California residents add 6% tax Add $300 shipping outside continental USADealer inquiries invited real stumbling blocks beginner construction really quite straightforward simple using common sport RC techniques Except spars hardwood plywood balsa lots Some substitutions cheaper materials could save lot money example -in sheet balsa fuselage sides could replaced door-skin ply backed up -in sq spruce longerons balsa formers ribs could cut foam core board dont mean criticism design just hints accomplish same thing having mortgage farm Super SunRay uncommon design very good flier wont see sitting next field plans available Ron Mangum PO Box 8244 Greensboro NC 27410 Waco UPF-7 plans UPF-7 opencockpit biplane similar contemporary PT-17 have soft spot heart aircraft because first open biplane ever flew got private ticket late Forties small field near Portsmouth VA field like era now covered houses Anyway owner field addition Aeronca Champs used training two airplanes really intrigued clipped-wing Monocoupe restoring other operational UPF-7 owner really wrapped up Monocoupe built display model complete planned color scheme traded model him check-out flying time Waco time effort well spent part Dave Richardsons UPF-7 quarter-scale plans show Quadra mount spans 86-in 733/4-in long estimated 23 lb shown plans just within comfortable capabilities Quadra first saw Daves prototype fly STARS rally 1980 Kioritz slightly larger engine allows little margin enor puts bit snap maneuvers Almost engines under 4 ci will fit nicely radial cowl plans consist three sheets approximately 3 ft 5 ft plus smaller sheet landing gear details addition well-written four-page instruction booklet questions came mind looking plans answered time finished reading booklet available Dave Rich ardson Star Route Deposit NY 13754 50cc Quadra other day got slightly latebut very welcomeChristmas present Im writing early January UPS dropped off brand new 50cc Quadra Its first ones off production line looks great havent chance run yet will soon results will next Big Bangers article Bob Beckman 8248 Holly Grove Ct Manassas VA 22110 RC Pylon Racing/Hager Continued page 52 fiters have hard time getting engine last contest let alone whole season FAI engine possible have engine last whole Racing season started Racing glow plugs 29 39 Now some over $2 Formula use plug per flight lucky some dont last whole flight FAI competition could possibly use same plug whole weekend April 1983 127