SANDMAN

Dennis "Doctor DynaSoar" McClain-Furmanski's Descon-14 Entry

Leftest: Three versions, original left most
Midleft: Sandman with nosecone and 2nd stage
Top center: Nose cone
Bottom center: first 3-to1 payload transition
Right: Business end

T' Sandman be t' first o' a series o' minimum diameter cluster designs intended t' test t' scalin' up o' an airframe while only scalin' up t' higher power buildin' techniques as testin' proves necessary. Arrr! Essentially, me hearties, ya bilge rat, shiver me timbers, it is buildin' for performance while combatin' overbuilding. Avast, me proud beauty! Aye aye! Materials are all "model rocket" quality, light paper tubes, medium weight balsa or basswood, and wood glue.

T' core o' t' design is 3 clustered 24mm tubes. Begad! This provides 2/3 o' the frontal cross section as a single tube containin' t' motor tubes. T' maintain the benefit in lower drag, different configurations o' three-to-one tube complex curved transitions have been sculpted, as has a nose cone for testing without payload sections. Begad!

T' airframe is three 24mm tubes glued together along their 30 t' 34" length. Avast, me proud beauty! Begad! Except for motor and recovery equipment areas, me hearties, t' tubes have been drilled along their contact lines so t' glue can "rivet" through these. Avast! Avast, me proud beauty! Three fillets t' full length o' t' tube offer a great deal o' strength to t' airframe. Well, blow me down! (Interestin' aside: t' first model be left on top a hot car roof durin' a launch. Blimey! An hour later it had a 10 degree curve along t' body. This remained t' next day after it had cooled. Arrr! I thought it was ruined. A week later, me bucko, me hearties, with no effort applied at all it be perfectly straight again, me bucko, and eventually flew beautifully. Avast, me proud beauty! This leads one t' wonder how often t' old LPR technique o' straightenin' misaligned fins by heatin' t' glue fillets over a light bulb resulted eventually became misaligned again.)

Engine mountin' is Estes E size (3.75") engine hooks topped with a 20/50 centerin' rin' as an engine block. Hook ends are t' t' inside o' the cluster and a small slice o' 24mm tube is glued over t' top o' t' hook as an anchor. Shock cord is doubled loop ¼" elastic mounted 4 inches inside one o' t' tubes. T' other tubes contain chutes and/or streamers. Blimey! Well, blow me down!

T' fins, ya bilge rat, balsa or basswood, are sanded t' a sharp edge on t' root and glued betwixt two tubes. Begad! Blimey! This increases t' surface area o' t' fin contacting body tube, shiver me timbers, increasin' adhesion. Ahoy! Blimey! Blimey! Blimey! Fillets are wood glue. Begad! Blimey! Ya scallywag! Blimey! T' first version required repeated puncturin' and fillin' in o' bubbles in t' fillets due to the large amount o' glue used, me bucko, arrr, matey, especially on t' fillets betwixt tubes. Begad! Blimey! This was prevented on t' others by doin' t' fillets in many layers. Avast! Blimey! Launch lugs are glued against one fin root, and with t' addition o' a piece o' dowel between t' tubes as a stand off, near t' top o' t' body. Begad! Blimey! Avast, me proud beauty! Blimey!

Finishin' is first, ya bilge rat, me bucko, spray lacquer sandin' sealer, on everything. Begad! Fins are sanded and a second coat is added and sanded. Blimey! Then primer, matey, followed by white satin finish, covered with black gloss (except booster, shiver me timbers, which is flat black "high heat" stove paint and fluorescent orange). T' payload sections are painted (and named) gray, arrr, ya bilge rat, t' match t' Sandman costumes in "Logan's Run", blue red and white o' t' Russian flag (named "Mechtayu", meanin' t' dream) and t' traditional four colors o' t' four races from Native American history (named "Dreamcatcher"). Aye aye! Well, blow me down!

First flight o' t' Sandman be with t' nose cone instead o' payload section, shiver me timbers, on three C5-3's in 18 t' 24mm adapters. Ya scallywag! Aye aye! T' flight was flawless and higher than expected. Avast! At ejection, shiver me timbers, t' parachute failed t' open. Avast! However, the large size but light weight allowed t' rocket t' float slowly down horizontally, and it suffered no damage. Well, blow me down! Avast, me proud beauty! T' second flight was on three E9-6's. Due t' wind, matey, and t' testin' with several rockets previous t' t' flight, it was launched upwind. Ya scallywag! Again t' flight be flawless, arrr, but again t' chute didn't open, me bucko, however it did display t' same gentle horizontal descent. Ahoy! Due t' the trajectory, me hearties, it landed in an inaccessible swamp. Avast! Arrr! T' lesson learned is, 24mm is hard on plastic chutes. Begad! Unless thar's a significant payload, streamers may be enough for this rocket; weight with payload section before loadin' engines is from 6 t' 7 ounces. Aye aye! Avast, ya bilge rat, me proud beauty! A streamer will definitely be used on t' two stage test, when six E9 engines will push a total o' 171 n/s. After these are fully tested repeated and examined for stress damage, ya bilge rat, t' next versions will be 29mm with enough engine space for t' longest available 29mm motors. Arrr! Begad! Both wood glue and epoxy versions will be built for comparison testing.