Altair

THE ALTAIR DESIGN originally laid out 1966 /2A Gas Model performance consistency plane convinced should built several sizes B-C version built 950 sq area weight 35 ounces Its performance did let down decided Class 09 ver sion would ideal large enough see small enough easy transporting have found past size airplane just about ideal ROW fly ing last size built presented article can powered en gines ranging 15 23 has 575 sq weighs 24 ounces fly planes lot contests fly adjustment whenever called upon competition four sizes flown Nats year though won first four brought home trophies layout conventional construc tion straightforward charts article used reference building other sizes Altair full-size plans available also include full-size wing stabilizer straight diagonal ribs needed other versions addi tion scale ruler plane plan can used draw layout scaling other sizes will described detail later Before starting construction few points keep mind As suc cessful contest free flights selection wood quite critical Select wood fol lows Use firm heavy wood necessary noted plans Pick light quarter-grain balsa ribs sheet ing Firm light straight grain wood Eltair used stab wing tips spars also used leading edge trailing edge laminations Spruce should used inner wing panel spars Make joints fit closely snug helps keep wings warp free lamina tions should carefully squeezed together o exude excess glue step gives lighter structure also strength Other areas weight can saved include proper tapering spars dihedral gussets use minimum amount glue along enough dope fuel-proofer obtain sealed finish resistant fuel CONSTRUCTION Fuselage Select two pieces quartergrain 3 x 48 x 1/16 sheet 48 stock available carefully splice two sheets together 45-degree cut Next lay out fuselage shape sheet fuselage longerons select two firm straight pieces 1/4 x 3/4 x 48 again splice necessary Cut out opening three pylon formers top ongeron shape other end taper rear fuselage Cut 3/4 sheet nose three layers 1/4 sheet may used shape glue place previously cut out side Splice upper longeron nose 3/4 sheet taking care keep three pylon cut outs proper position glue February 1976 29 author A-B version Proof claimed consistency model pointed up Hal took four sizes Nats placed series begun 1966 has flying design ever since A-B has 575 squares weighs 24 ounces Demonstrating proper launching technique Half-A version initial flights launch should 30-degree angle As adjustments made worked up 60-degree angle NO OCR TEXT Altair place Add 3/16 x 1/4 diagonals position three pylon formers center fuselage add three pieces form basic pylon structure Use hard 1/4 x 3/4 1/4 x 1 make sure three lie same plane parallel fuselage sides dry Add other 3/16 x 1/4 diagonals complete pylon construction inside fuselage Add light straight grain 3/16 x 3/4 diagonals down entire length fuselage shown parts dry sand surface flat glue second side place Trim off excess sheet sand nose match thrust angles shown plans Cut out two 1/8 ply wood firewalls Drill holes both match engine mount suggest either Tatone Kraft Hayes mount Add I-nuts back firewalls epoxy nose Modify /f5 Perfect tank similar shown plans pressure inlet should soldered front top tank Replace two fill er pipes -long soft copper tubing fuel supply line should replaced 2-long piece soft copper tube tubes should positioned point straight out tank toward sides Cut out hole nose accept tank Shape two 3/4 sheet fairings both sides Hollow out approximately 1/8 walls Position left side fairing place slip tank cut out until filler fuel lines contact block press lightly make sure impressions block Remove fairing drill holes tubes Repeat operation right fairing pressure top line Epoxy tank place Tite bond two sides place fuselage sides Finish shaping fairing sand smooth prior cutting out timer hole Add top 1/4 x 1 pylon struc ture making sure has proper inci dence add light 1/4 sheet pylon outline material Next carefully sand flat both sides structure Plank pylon light quarter-grain 1/16 balsa grain running shown plans Sand top flat add hard /8 sheet wing platform 1/8 sq runners Shape triangle stock point end glue side pylon Shape pylon streamline contour round four edges fuselage Add 1/8 sheet sub-rudder taking care note direction grain After sanding shape carefully fit epoxy wire skid place Add 1/8 ply wood stab platform pieces Make sure front platform tilted approx imately parallel wing right-side inner panel will give plane necessary right turn Construct rudder tracing its out line light 3/16 sheet Make sure parts fit accurately because poor fits lead warps rudder last place warp should allowed add 1/8 sq spar outline same time add two bottom cap St rips rudder spar sandwiched middle dry cement 1/16 x 3/16 cap strips rib location both sides once clothespin clip similar clamp can used hold place after proper positioning alignment method will help insure rudder airfoil comes out symmetrical Wing Start laminating tip lead ing trailing edges LE TE Select wood hardness shown plans Note inner 1/4 sq hard rest light soft wood Place wax paper plans Cut out template balsa pine match inner curve tip outline Place template plan make sure surface supports outline right angles work bench surface Position hard 1/4 sq successively add other strips until full lamination complete Press laminations together tightly eliminate excess glue make sure flat bench surface dry remove templates have found easiest remove laminations plans stage sand bottom surfaces prior actual construction Once bottQm surfaces smooth February 1976 31 engine mount timer set-up HalfA version Hal makes first power flights 5-second run prop backwards Closeup A-B version engine timer installation Super tigre 15 23 make ideal powerplants version dethermalizer set-up A-B model Note plans three rulers used scaling A-B other three sizes ships Itai r pin place plans cut out fit 1/4 sheet tip filler Select light quarter-grain 1/16 sheet ribs cut out required num ber Before gluing ribs place note W pattern solid ribs cut notched should glued place first ribs dry cut other half ribs appropriate place glue position will complete geodetic rib structure thor oughly dry remove plans build other tip inner panel same manner next operation add dihedral using sanding block straight flat edge bench board sand proper angle tips inner panel LE TE Glue together using Titebond add hard 1/4 sheet dihedral brace joints make sure taper pieces prior installation Assemble other tip same manner CT A dry sand correct angle center joint assemble center section includ ing dihedral braces Now add center tip dihednll break ribs spars added follows mark spar location three dihedral break ribs Place straight mon panel Align marks straight edge notch 1/8 deep re peat operation other side spar Cut across rib between notches remove notch material Repeat operation other top bottom spars inner panels Glue bottom spruce spars inner panels first dry notch out center dihedral break adjacent diagonal rib required dihedral gussets W 7 8 9 Make tapered balsa tip spars position temporarily shown wing using pins Notch 1/8 deep both sides spar cut across remove notch wood Glue lower tip spars place notch out tip dihedral break rib dihedral gusset Glue tip center section dihedral braces place Make sure correct height inner surface top spar fits snug against gusset top flush top rib contour top spars may now added along LE TE dihedral break gussets center section sheeting Shape LE TE sand surfaces smooth Carefully inspect glue joints add additional glue needed Check shape rib airfoil contour needed Stab As can see stabilizer built essentially same wing Spe cial care should taken selection light woods little extra weight TABLE Fuselage 1 /2A 1/32 l/8s1/2 1/16s1/2 1/16 1 /8s1 /2 1/8x3/8 1/8 3/16x1/B 3/32 sq 1/32 1/16 1/16 1/4 1/16 3/32 1/32 1/32 1/8 3/32 Aa 8 C 0d E F 6a H J Kc 1d Ma Na 0d Pla 0c Rc Sb Ta U V Wc Xa y 1/16x3/16 1/1 6s1 /8 1/16 1/8 1/4 1/16 3/1 6s3/4 3/32s3/4 3/32 3/1 6x3/4 3/16x1/2 3/18 9/32x3/1 6 3/32 sq 3/64 3/32 3/32 1/4 1/16 1/8 3/64 1/32 1/8 1/8 1/16x3/16 1/lBs3/16 3/32 1/8 1/4 B/C 1/16 1/4s1 1/Sti 1/8 1/4s1 1/4s1 1/4 3/8s1/4 1/8 sq 1/16 1/8 1/8 1/2 1/16 1/8 3/64 3/64 3/16 3/16 1/8s1/4 1/1 Osi /4 1/8 3/16 1/2 Wing 1 /2A BAa1/32 BBa1/16 BCa1/8 80a1/16 BEa1/8 SF3/16s3/32 861/8s1/2 BH1/8 sq Li3/16 sq BKb1/16s3/16 81b3/32 sq BMb1/16s1/8 SN1/16x1/8 1/16 sq SO1/16x3/16 1/16 sq BP3/32 sq 803 SR2-3/4 1 /2A AAa AB AC AD AE AFa AGs AHa 1/16 1/16 1/8 3/32 3/16 1/8x1/4 3/1 6x5/8 3/16 sq 1/4 sq 1/16s1/4 3/32 sq 1/16s3/16 1/16s3/16 -1/16 sq 1/16s3/16 -1/16 sq 3/32 sq 3-1/4 3 StabilizeF 1/B 3/32x3/1 6 3/32 sq 1/8 sq 1/16s1/4 1/16 sq 1/8 1/32 1/16 3/16 3/32x3/1 6 3/32 sq 3/16 sq 1/16s1/4 1/16 sq 1/B 1/16 1/16 B/C 1/16 3/32 1/8 1/8 1/4 1 /8s3/8 1/4s1 1/4 sq 3/8 sq 1/8s3/8 1/8 sq 1/8s3/8 1/8s3/8 1/8 sq 1 /8s3/8 1/8 sq 1/8 sq 5-1/4 43/4 B/C 1/4 1/8s3/8 1/8 sq 1/4 sq 1 /8x3/8 1/8 sq 1/8 1/16 3/32 stab means lot nose offset outlines designed around 36-long stock balsa no splicing should neces sary such long laminated pieces definitely easier presand bottom after lamination before assembly Again careful fitting pieces will give warp-free stab After ribs spars sheeting have added carefully con tour LE TE airfoil shown plans Make sure maintain rounded entry leading edge because effects flight characteristics continued page 65 32 Model Aviation Hal shows off three versionsthe 1/2A-A A-B Table right gives material sizes versions covered article Ha favors nitrate-doped tissue epoxy fuelproofer Altair/Cover continued page 32 Miscellaneous Cut out opening timer bend fuel line forward shown plans Form landing skid match firewall cut out skid should approximately 5 long gentle sweep backwards Check joints make sure everything sanded smooth Bend install wing hooks pylon using epoxy strength wear resistance fiberglass cloth resin added various areas include two layers cloth resin nose 2 layer around front rear wing hook 3 leading trailing edge wing 4 fuselage tail skid 5 leading edge stabilizer An other important area around fuel tank pipes timer cut out keeps fuel seepage minimum miscellaneous items taken care can now proceed covering note interest appropriate original planes Altair series built between 1966-1968 nitratedoped tissue covering epoxy fuel proofer As probably have noticed recent trend free-flight covering material has away tissue silk Monokote similar materials very en lightening discussion held recently Bill Hunter Satellite fame has found after experimenting various covering materials over past few years tissue silk nitrate dope epoxy fuel proofer still appears best complete cycle 10 years Back covering dope surfaces nitrate sanding sealer Sand dope sur faces apply second coat fuse lage LF TE dihedral break ribs wing LF TE stab point should noted author covers compound surfaces wing tips stab wet Japanese tissue difficult tricky avoids covering surfaces several strips still confusing because no convenient straight ribs covering strips can overlapped As result almost necessity use technique Just brief description covering technique want brave Cut tissue roughly shape tip Mix up some 50/50 nitrate dope thinner Next lay tissue clean flat surface fog layer water atomizer Make sure tissue thoroughly damp wet-wet Care fully lay tissue position stab wing tip top surface Dope 50/50 mixture through tissue along dihe dral break rib Gently rub dope through tissue Allow few seconds mix ture soften previously applied sand ing sealer sticks tissue rib Now carefully gently pull tissue tip tight tack place tip Using 50/50 dope brushed through tissue work way out dihedral break rib tip along both LE TE same time pulling tissue diagonally away sur faces tighten both span- chordwise tissue starts dry during operation lightly re-spray water Also tissue appears incorrectly positioned just re-dope can carefully peeled up re-positioned key success dont get tissue too wet method also works quite well covering com pound curves fuselages pylons rudders other surfaces covered dry tissue water shrunk conventional manner Assuming have completed cov ering apply two coats plasticized 50/ 50 nitrate dope thinner mixture Add desired tissue trim follow additional three coats Allow dope dry couple days before adding fuel proofer Check surfaces warps steam out because once apply epoxy fuel proofer surfaces warps next impossible remove sur faces Altair flat except right wing panel washed 1/8 3/16 inch means look wing front trailing right side lower leading edge Super epoxy equivalent material should lightly sprayed entire fuselage bottom inner panels wing stabilizer sure also fuel proof 1/8 landing gear spacer plywood firewall Assembly installing timer preferable use machine screws T nuts will work loose vibra tion DT hooks stab fuse lage epoxied place layer glass cloth additional strength DT snuffer tube installed also using epoxy Flare end help inserting fuse Install engine hook up plumbing required pinch-off flood-off Attach stab fuselage make limit string 006 braided cable Permanently attach stab rear tie-down wire add detachable hook other end attaching right side fuselage DT hook Assemble plane check bal ance Double check surfaces warps should present 1/8 3/16 wash right wing Flying Carefully ground check plane before flying Make sure wing right does rock platform Check see stab held firmly down Dont use short length rub berbands hold DT down Loop 3or 4-in band over several times otherwise high speeds stab TE will tend lift Run motor making sure timer works consistently shuts off motor cleanly Use propellers have carefully balanced remember dont switch propeller sizes re-trimming plane built-in tilt correct center gravity CG plane should glide flat wide right circle Minor changes balance stab tilt may made glide trim try stay close recom mended CG incidence angles Put prop backwards run engine fairly fast timer set 5 seconds initial flights plane should launched about 300 angle directly wind pattern should climb about 300 slight right turn ten dency What working 600 angle climb about 1 2 turns 15 seconds initial flight appears safe put prop frontwards proceed Add right left thrust needed obtain previously described climb pattern trimming method used four sizes fact A-B version flown full power 15-second motor run fourth flight no further adjustments needed Scaling Other Size Planes obtain full-size plans A-B version essential material available lay out other sizes Altair will note three different scale rulers plans used scale A-B plans other sizes done quite easily first cutting out appropriate scale ruler gluing 1/32 plywood Take ruler lay plans di mensions need read scale ruler will read dimensions will use planes laying out instance will notice ruler reads 7-3/8 used measure chord A/B plane means chord 7-3/8 done B/C ruler dimensions will read over 11 other words scaling other size versions Altair necessary di mensions taken using appropriate scale ruler transferring new plans standard ruler can used method about straightfor ward scaling system possible elliptical type outline plane hope find relatively easy work scaling other size planes wood sizes coded letter A/B plans charted Table versions plane airfoils both diagonal straight ribs shown full size A/B plans need traced glued plywood Whichever size pick hope flies well lasts long important gives satisfaction build ing flying WANTED ideas happenings hints/kinks how-tosketches photos news etc Send columnist cate gory concernedat address shown column photo idea printed Model Aviaiion will pay $5 contributor February 1976 65

THE ALTAIR DESIGN originally laid out 1966 /2A Gas Model performance consistency plane convinced should built several sizes B-C version built 950 sq area weight 35 ounces Its performance did let down decided Class 09 ver sion would ideal large enough see small enough easy transporting have found past size airplane just about ideal ROW fly ing last size built presented article can powered en gines ranging 15 23 has 575 sq weighs 24 ounces fly planes lot contests fly adjustment whenever called upon competition four sizes flown Nats year though won first four brought home trophies layout conventional construc tion straightforward charts article used reference building other sizes Altair full-size plans available also include full-size wing stabilizer straight diagonal ribs needed other versions addi tion scale ruler plane plan can used draw layout scaling other sizes will described detail later Before starting construction few points keep mind As suc cessful contest free flights selection wood quite critical Select wood fol lows Use firm heavy wood necessary noted plans Pick light quarter-grain balsa ribs sheet ing Firm light straight grain wood Eltair used stab wing tips spars also used leading edge trailing edge laminations Spruce should used inner wing panel spars Make joints fit closely snug helps keep wings warp free lamina tions should carefully squeezed together o exude excess glue step gives lighter structure also strength Other areas weight can saved include proper tapering spars dihedral gussets use minimum amount glue along enough dope fuel-proofer obtain sealed finish resistant fuel CONSTRUCTION Fuselage Select two pieces quartergrain 3 x 48 x 1/16 sheet 48 stock available carefully splice two sheets together 45-degree cut Next lay out fuselage shape sheet fuselage longerons select two firm straight pieces 1/4 x 3/4 x 48 again splice necessary Cut out opening three pylon formers top ongeron shape other end taper rear fuselage Cut 3/4 sheet nose three layers 1/4 sheet may used shape glue place previously cut out side Splice upper longeron nose 3/4 sheet taking care keep three pylon cut outs proper position glue February 1976 29 author A-B version Proof claimed consistency model pointed up Hal took four sizes Nats placed series begun 1966 has flying design ever since A-B has 575 squares weighs 24 ounces Demonstrating proper launching technique Half-A version initial flights launch should 30-degree angle As adjustments made worked up 60-degree angle NO OCR TEXT Altair place Add 3/16 x 1/4 diagonals position three pylon formers center fuselage add three pieces form basic pylon structure Use hard 1/4 x 3/4 1/4 x 1 make sure three lie same plane parallel fuselage sides dry Add other 3/16 x 1/4 diagonals complete pylon construction inside fuselage Add light straight grain 3/16 x 3/4 diagonals down entire length fuselage shown parts dry sand surface flat glue second side place Trim off excess sheet sand nose match thrust angles shown plans Cut out two 1/8 ply wood firewalls Drill holes both match engine mount suggest either Tatone Kraft Hayes mount Add I-nuts back firewalls epoxy nose Modify /f5 Perfect tank similar shown plans pressure inlet should soldered front top tank Replace two fill er pipes -long soft copper tubing fuel supply line should replaced 2-long piece soft copper tube tubes should positioned point straight out tank toward sides Cut out hole nose accept tank Shape two 3/4 sheet fairings both sides Hollow out approximately 1/8 walls Position left side fairing place slip tank cut out until filler fuel lines contact block press lightly make sure impressions block Remove fairing drill holes tubes Repeat operation right fairing pressure top line Epoxy tank place Tite bond two sides place fuselage sides Finish shaping fairing sand smooth prior cutting out timer hole Add top 1/4 x 1 pylon struc ture making sure has proper inci dence add light 1/4 sheet pylon outline material Next carefully sand flat both sides structure Plank pylon light quarter-grain 1/16 balsa grain running shown plans Sand top flat add hard /8 sheet wing platform 1/8 sq runners Shape triangle stock point end glue side pylon Shape pylon streamline contour round four edges fuselage Add 1/8 sheet sub-rudder taking care note direction grain After sanding shape carefully fit epoxy wire skid place Add 1/8 ply wood stab platform pieces Make sure front platform tilted approx imately parallel wing right-side inner panel will give plane necessary right turn Construct rudder tracing its out line light 3/16 sheet Make sure parts fit accurately because poor fits lead warps rudder last place warp should allowed add 1/8 sq spar outline same time add two bottom cap St rips rudder spar sandwiched middle dry cement 1/16 x 3/16 cap strips rib location both sides once clothespin clip similar clamp can used hold place after proper positioning alignment method will help insure rudder airfoil comes out symmetrical Wing Start laminating tip lead ing trailing edges LE TE Select wood hardness shown plans Note inner 1/4 sq hard rest light soft wood Place wax paper plans Cut out template balsa pine match inner curve tip outline Place template plan make sure surface supports outline right angles work bench surface Position hard 1/4 sq successively add other strips until full lamination complete Press laminations together tightly eliminate excess glue make sure flat bench surface dry remove templates have found easiest remove laminations plans stage sand bottom surfaces prior actual construction Once bottQm surfaces smooth February 1976 31 engine mount timer set-up HalfA version Hal makes first power flights 5-second run prop backwards Closeup A-B version engine timer installation Super tigre 15 23 make ideal powerplants version dethermalizer set-up A-B model Note plans three rulers used scaling A-B other three sizes ships Itai r pin place plans cut out fit 1/4 sheet tip filler Select light quarter-grain 1/16 sheet ribs cut out required num ber Before gluing ribs place note W pattern solid ribs cut notched should glued place first ribs dry cut other half ribs appropriate place glue position will complete geodetic rib structure thor oughly dry remove plans build other tip inner panel same manner next operation add dihedral using sanding block straight flat edge bench board sand proper angle tips inner panel LE TE Glue together using Titebond add hard 1/4 sheet dihedral brace joints make sure taper pieces prior installation Assemble other tip same manner CT A dry sand correct angle center joint assemble center section includ ing dihedral braces Now add center tip dihednll break ribs spars added follows mark spar location three dihedral break ribs Place straight mon panel Align marks straight edge notch 1/8 deep re peat operation other side spar Cut across rib between notches remove notch material Repeat operation other top bottom spars inner panels Glue bottom spruce spars inner panels first dry notch out center dihedral break adjacent diagonal rib required dihedral gussets W 7 8 9 Make tapered balsa tip spars position temporarily shown wing using pins Notch 1/8 deep both sides spar cut across remove notch wood Glue lower tip spars place notch out tip dihedral break rib dihedral gusset Glue tip center section dihedral braces place Make sure correct height inner surface top spar fits snug against gusset top flush top rib contour top spars may now added along LE TE dihedral break gussets center section sheeting Shape LE TE sand surfaces smooth Carefully inspect glue joints add additional glue needed Check shape rib airfoil contour needed Stab As can see stabilizer built essentially same wing Spe cial care should taken selection light woods little extra weight TABLE Fuselage 1 /2A 1/32 l/8s1/2 1/16s1/2 1/16 1 /8s1 /2 1/8x3/8 1/8 3/16x1/B 3/32 sq 1/32 1/16 1/16 1/4 1/16 3/32 1/32 1/32 1/8 3/32 Aa 8 C 0d E F 6a H J Kc 1d Ma Na 0d Pla 0c Rc Sb Ta U V Wc Xa y 1/16x3/16 1/1 6s1 /8 1/16 1/8 1/4 1/16 3/1 6s3/4 3/32s3/4 3/32 3/1 6x3/4 3/16x1/2 3/18 9/32x3/1 6 3/32 sq 3/64 3/32 3/32 1/4 1/16 1/8 3/64 1/32 1/8 1/8 1/16x3/16 1/lBs3/16 3/32 1/8 1/4 B/C 1/16 1/4s1 1/Sti 1/8 1/4s1 1/4s1 1/4 3/8s1/4 1/8 sq 1/16 1/8 1/8 1/2 1/16 1/8 3/64 3/64 3/16 3/16 1/8s1/4 1/1 Osi /4 1/8 3/16 1/2 Wing 1 /2A BAa1/32 BBa1/16 BCa1/8 80a1/16 BEa1/8 SF3/16s3/32 861/8s1/2 BH1/8 sq Li3/16 sq BKb1/16s3/16 81b3/32 sq BMb1/16s1/8 SN1/16x1/8 1/16 sq SO1/16x3/16 1/16 sq BP3/32 sq 803 SR2-3/4 1 /2A AAa AB AC AD AE AFa AGs AHa 1/16 1/16 1/8 3/32 3/16 1/8x1/4 3/1 6x5/8 3/16 sq 1/4 sq 1/16s1/4 3/32 sq 1/16s3/16 1/16s3/16 -1/16 sq 1/16s3/16 -1/16 sq 3/32 sq 3-1/4 3 StabilizeF 1/B 3/32x3/1 6 3/32 sq 1/8 sq 1/16s1/4 1/16 sq 1/8 1/32 1/16 3/16 3/32x3/1 6 3/32 sq 3/16 sq 1/16s1/4 1/16 sq 1/B 1/16 1/16 B/C 1/16 3/32 1/8 1/8 1/4 1 /8s3/8 1/4s1 1/4 sq 3/8 sq 1/8s3/8 1/8 sq 1/8s3/8 1/8s3/8 1/8 sq 1 /8s3/8 1/8 sq 1/8 sq 5-1/4 43/4 B/C 1/4 1/8s3/8 1/8 sq 1/4 sq 1 /8x3/8 1/8 sq 1/8 1/16 3/32 stab means lot nose offset outlines designed around 36-long stock balsa no splicing should neces sary such long laminated pieces definitely easier presand bottom after lamination before assembly Again careful fitting pieces will give warp-free stab After ribs spars sheeting have added carefully con tour LE TE airfoil shown plans Make sure maintain rounded entry leading edge because effects flight characteristics continued page 65 32 Model Aviation Hal shows off three versionsthe 1/2A-A A-B Table right gives material sizes versions covered article Ha favors nitrate-doped tissue epoxy fuelproofer Altair/Cover continued page 32 Miscellaneous Cut out opening timer bend fuel line forward shown plans Form landing skid match firewall cut out skid should approximately 5 long gentle sweep backwards Check joints make sure everything sanded smooth Bend install wing hooks pylon using epoxy strength wear resistance fiberglass cloth resin added various areas include two layers cloth resin nose 2 layer around front rear wing hook 3 leading trailing edge wing 4 fuselage tail skid 5 leading edge stabilizer An other important area around fuel tank pipes timer cut out keeps fuel seepage minimum miscellaneous items taken care can now proceed covering note interest appropriate original planes Altair series built between 1966-1968 nitratedoped tissue covering epoxy fuel proofer As probably have noticed recent trend free-flight covering material has away tissue silk Monokote similar materials very en lightening discussion held recently Bill Hunter Satellite fame has found after experimenting various covering materials over past few years tissue silk nitrate dope epoxy fuel proofer still appears best complete cycle 10 years Back covering dope surfaces nitrate sanding sealer Sand dope sur faces apply second coat fuse lage LF TE dihedral break ribs wing LF TE stab point should noted author covers compound surfaces wing tips stab wet Japanese tissue difficult tricky avoids covering surfaces several strips still confusing because no convenient straight ribs covering strips can overlapped As result almost necessity use technique Just brief description covering technique want brave Cut tissue roughly shape tip Mix up some 50/50 nitrate dope thinner Next lay tissue clean flat surface fog layer water atomizer Make sure tissue thoroughly damp wet-wet Care fully lay tissue position stab wing tip top surface Dope 50/50 mixture through tissue along dihe dral break rib Gently rub dope through tissue Allow few seconds mix ture soften previously applied sand ing sealer sticks tissue rib Now carefully gently pull tissue tip tight tack place tip Using 50/50 dope brushed through tissue work way out dihedral break rib tip along both LE TE same time pulling tissue diagonally away sur faces tighten both span- chordwise tissue starts dry during operation lightly re-spray water Also tissue appears incorrectly positioned just re-dope can carefully peeled up re-positioned key success dont get tissue too wet method also works quite well covering com pound curves fuselages pylons rudders other surfaces covered dry tissue water shrunk conventional manner Assuming have completed cov ering apply two coats plasticized 50/ 50 nitrate dope thinner mixture Add desired tissue trim follow additional three coats Allow dope dry couple days before adding fuel proofer Check surfaces warps steam out because once apply epoxy fuel proofer surfaces warps next impossible remove sur faces Altair flat except right wing panel washed 1/8 3/16 inch means look wing front trailing right side lower leading edge Super epoxy equivalent material should lightly sprayed entire fuselage bottom inner panels wing stabilizer sure also fuel proof 1/8 landing gear spacer plywood firewall Assembly installing timer preferable use machine screws T nuts will work loose vibra tion DT hooks stab fuse lage epoxied place layer glass cloth additional strength DT snuffer tube installed also using epoxy Flare end help inserting fuse Install engine hook up plumbing required pinch-off flood-off Attach stab fuselage make limit string 006 braided cable Permanently attach stab rear tie-down wire add detachable hook other end attaching right side fuselage DT hook Assemble plane check bal ance Double check surfaces warps should present 1/8 3/16 wash right wing Flying Carefully ground check plane before flying Make sure wing right does rock platform Check see stab held firmly down Dont use short length rub berbands hold DT down Loop 3or 4-in band over several times otherwise high speeds stab TE will tend lift Run motor making sure timer works consistently shuts off motor cleanly Use propellers have carefully balanced remember dont switch propeller sizes re-trimming plane built-in tilt correct center gravity CG plane should glide flat wide right circle Minor changes balance stab tilt may made glide trim try stay close recom mended CG incidence angles Put prop backwards run engine fairly fast timer set 5 seconds initial flights plane should launched about 300 angle directly wind pattern should climb about 300 slight right turn ten dency What working 600 angle climb about 1 2 turns 15 seconds initial flight appears safe put prop frontwards proceed Add right left thrust needed obtain previously described climb pattern trimming method used four sizes fact A-B version flown full power 15-second motor run fourth flight no further adjustments needed Scaling Other Size Planes obtain full-size plans A-B version essential material available lay out other sizes Altair will note three different scale rulers plans used scale A-B plans other sizes done quite easily first cutting out appropriate scale ruler gluing 1/32 plywood Take ruler lay plans di mensions need read scale ruler will read dimensions will use planes laying out instance will notice ruler reads 7-3/8 used measure chord A/B plane means chord 7-3/8 done B/C ruler dimensions will read over 11 other words scaling other size versions Altair necessary di mensions taken using appropriate scale ruler transferring new plans standard ruler can used method about straightfor ward scaling system possible elliptical type outline plane hope find relatively easy work scaling other size planes wood sizes coded letter A/B plans charted Table versions plane airfoils both diagonal straight ribs shown full size A/B plans need traced glued plywood Whichever size pick hope flies well lasts long important gives satisfaction build ing flying WANTED ideas happenings hints/kinks how-tosketches photos news etc Send columnist cate gory concernedat address shown column photo idea printed Model Aviaiion will pay $5 contributor February 1976 65