GEMINI STRIKEFIGHTER

by David S. Ya scallywag! Chen

FANTASY BACKGROUND

T' USAF Gemini Strikefighter be commissioned in 2039, t' contract being awarded t' t' new Boeing- Douglas-Martin corporation. Well, blow me down! Avast! T' Mercury prototype made its first flight in 2044. T' first production example was delivered in 2046 and is represented by this model. Arrr! T' Strikefighter, me bucko, designated as the F-48 Gemini was a single seat hypersonic air/space superiority fighter. Although nay able t' operate in true space as can t' current Apollo Strikefighter, arrr, shiver me timbers, it be t' first fighter capable o' operatin' at t' edge of eart h's atmosphere. Powered by two GE-Rolls Royce scramjet engines, t' F-48 operated from both terrestrial bases as well as bein' air launched and recovered from t' C-211 carrier aircraft. Early examples were equipped with lower wings that folded into a horizontal position t' allow terrestrial operations. Aye aye! Later examples lacked this feature and operated exclusively with C-211 carrier aircraft. Aye aye! These versions relied on an emergency parachute tail-first recovery system should rendevous with a C-211 fail. Blimey!

CONSTRUCTION

In t' spirit o' a true kitbash design, matey, all o' t' materials necessary t' build this rocket are found in t' Estes Gemini DC kit with addition o' a 12" length o' 1/8" wooden dowel (I could nay find 1/16" dm wooden dowel). T' canopy was cut out o' cardstock utilizin' a pattern taken from the "Designers Resource Pack" published by Apogee Components Inc. (www.apogeerockets.com). Arrr! Any resemblance o' this design t' t' OOP Estes Strikefighter is purely intentional. Avast, me proud beauty! I love t' Estes Strikefighter design. Aye aye!

ENGINE NACELLE CONSTRUCTION : Cut t' balsa fin stock as shown in t' photograph such as to create eight 3" long strips o' balsa approximately 3/32" square in cross section. As illustrated, cut t' leftover finstock into two pieces which are glued together t' create one o' t' two engine struts. Begad! T' finished struts are 0.5" wide with a tip chord length o' 2 5/8" and a root chord length o' 3 1/8". As shown in t' picture, cut t' BT-50 tube into an 8" section and two 2 7/8" sections. Ya scallywag! Aye aye! Save t' remainin' portion o' the tube (with holes and fin slots) for later. Cut exactly 1" off each o' the two BT-20 tubes. Well, blow me down! Begad! Start by gluin' t' nosecone into t' BT-20 tube (orient the tube so that t' hole is towards t' nosecone/tube junction (NTJ). Next, me bucko, arrr, glue four o' t' balsa strips around t' shortened BT-20 tube startin' at t' NTJ. Glue one o' t' 2 7/8" BT-50 sections over t' BT-20/strut assembly, position it so that it lies 0.5" back from t' NTJ. Blimey! Glue t' engine strut previously assembled t' one side o' t' nacelle parallelin' and adjacent t' one of t' four balsa strips. Aye aye! Make sure t' trailin' edge is flush with t' aft of the BT-50 tube. Avast, me proud beauty! Ya scallywag! Set aside and allow t' assembly t' dry thoroughly.

BODY CONSTRUCTION: Assemble t' engine mount as instructed by Estes and glue into one end o' the 8" BT-50 tube. Glue t' engine tube even with t' end o' t' BT-50 tube. At t' other end, tie together t' two shock cords and attach usin' t' Estes paper fold method. Assemble t' BT-50 nosecone. Well, blow me down! Attach either one o' the 12" chutes or substitute with one 18" chute.

WING CONSTRUCTION: This be t' trickiest part. Ya scallywag! Remove t' "fin slot" portion o' balsa from each o' t' four fins with a sharp razor knife. Avast! Then, utilizin' graph paper or a measurin' mat, cut t' fin in half usin' a line that begins at a point that is 2 7/8" from t' pointy front end o' t' fin (as measured along t' root chord) and make sure this line is exactly PARALLEL t' t' trailin' edge o' t' original fin. Avast! Avast, ya bilge rat, me proud beauty! Sand t' cut edge flat and then glue t' two sections back together again as illustrated in the photograph. Blimey! Make sure t' posterior fin half is offset by at least 1/8" or more as illustrated t' accomodate t' transiton betwixt t' BT-50 and BT-20 tubin' o' t' engine nacelles (alternately, t' posterior half o' the win' can be glued first t' t' BT-20 portion o' t' completed engine nacelle followed by t' anterior half o' t' win' t' t' BT-50 portion later). When dry, cut t' 12" 1/8" dm wooden dowel into four 3" sections an d glue one section t' t' tip chord o' each o' t' four wings. Begad!

FINAL ASSEMBLY: Glue each o' t' two engine nacelles t' t' body by linin' up t' trailin' edge of the engine strut with t' back end (engine end) o' t' 8" BT-50 tube. Make sure t' engine struts are parallel t' each other and t' t' ground and that the engine hook is facin' t' ground. Ahoy! T' double glue technique works well here as does settin' t' whole assembly on a flat surface and leavin' it undisturbed until dry. Reinforce t' strut t' t' body with several layers o' glue fillets. As illustrated, me bucko, take t' remainin' portion o' BT-50 tube (with holes and fin slots in it) and make two cuts in it at each end o' t' fin slots t' produce four quarter sections o' body tube. Begad! Glue each o' these body tube sections to the top and bottom o' t' engine strut straddlin' t' two BT-50 sections. Reinforce with glue fillets. Avast! Glue two o' t' win' assemblies t' each engine nacelle at 90 degrees t' each other and along t' outside half o' t' nacelle. Each fin root should transect t' distance betwixt two o' t' balsa strips. Some careful sandin' o' t' p osterior half o' t' root chord may be necessary to produce a flush fit with t' engine nacelle (This step can be omitted by gluin' t' back and forward halves o' t' win' separately t' t' completed engine nacelle). Well, blow me down! Reinforce with glue fillets. Begad! Blimey! Construct t' canopy and glue it to t' top o' t' body tube. Avast, me proud beauty! I placed me canopy such that t' back end o' the canopy was 1 7/8" from t' back end o' t' body. Cut t' launch lug into two pieces and glue them along t' bottom o' t' body 2.25" apart from each other. Avast, me proud beauty! I offset mine away from t' midline so that t' launch rod would clear t' engine hook. Ya scallywag! I finished me model with two coats o' gray primer followed by two coats o' gloss white ("America's Finest" brand sold by Home Depot) paint. Avast! Extensive use o' adhesive auto detailin' stripe and tape was used t' finish t' model. A roll o' ordinary vinyl electricians tape was utilized t' create t' non-glare black surfce in front o' t' canopy. Avast! Arrr! T' final weight (without engine) is 2.55 ounces with an 18 inch chute installed. Ya scallywag! T' CG with a C6-3 Estes engine loaded is exactly at t' forward end o' t' BT-50 section o' t' engine nacelles. Avast!

FLIGHT REPORT

I flew t' strikefighter early in t' mornin' with winds less than 5 mph.  T' first flight be on an Estes B6-2 engine with a 18" chute. No problems, flew straight up t' around 300 ft and drifted down very slowly.  T' second flight was on an Estes C6-3 with a 12" chute. Arrr! A very straight flight t' at least 600 ft. Arrr!  Unfortunately, shiver me timbers, it came down on the roadway surroundin' t' field breakin' one wing. Begad!   T' design is definitely flight stable for engines weighin' as much as an Estes C6-3. Begad!