Build this rocket contest (Spaceship Design), ya bilge rat, ya bilge rat, ya bilge rat, Design entry F4. Ya scallywag! Begad!

Name: Explorer (EMRR Experimental)

This is nay much o' a write-up but t' rocket that I built did nay have much o' a design. Last year I took special care t' print out t' photo o' t' rocket that I intended t' build, matey, measured everythin' and created scale drawings with multiple views o' what I wanted t' build. Avast! Blimey! This year I didn't think I would even have time t' get an entry done, when suddenly we were given a two-week extension. Arrr! Blimey! Aye aye! Blimey! I had found a shampoo bottle (a Suave kids shampoo, Monster fruit scent) that resembled part o' t' main body o' t' rocket so I cleaned it up and was off. Avast! Blimey! Avast! Blimey! Due t' time constraints and just to see if I could, ya bilge rat, I built this as a completely seat-of-the-pants kind o' design. Begad! Blimey! I measured little or nothin' but sized things as I went along, shiver me timbers, tryin' them for fit and markin' cut lines or tryin' things out with cardstock and then transferrin' t' "design" t' balsa or cardboard. Arrr! Blimey! Arrr! Blimey! T' nosecone and other transitions were just formed out of cardstock and cut t' fit. Avast, me proud beauty! Blimey! T' bridge section that sticks up at t' front o' t' rocket is several pieces o' scrap balsa from a Cub Scout rocket buildin' session, me bucko, glued together and carded t' shape with a second piece o' dowel glued on top.

T' top o' t' shampoo bottle be removed (later carved a bit and used as one o' t' attachments that appear on the rocket) and t' original openin' bored out with a 1-1/8" spade bit t' make room for t' central BT-50. Avast! A used D12-3 casin' was used (with t' inside end havin' several layers removed) t' transition through t' bottle top. Begad! Aye aye! Inside, I used t' centerin' "rings" (ovals) t' form an internal baffle so that t' BT-20 tubes could eject the recovery system in t' event o' a central motor failure. Ya scallywag! T' central tube has an 18 mm openin' on one side, me bucko, ya bilge rat, matey, followed by a balsa block and then another openin' on t' opposite side. Blimey! T' gaps betwixt t' BT inside t' baffle are sealed with yellow glue so that all o' t' ejection gases are forced t' pass around t' tubes before continuin' t' t' top o' the rocket. Begad! Well, blow me down!

For stability, I used t' cardboard cutout method t' locate t' approximate CP and then tried t' locate t' CG one diameter (usin' t' wide part o' t' oval as t' diameter) ahead o' t' CP by fillin' t' nosecone with #6 lead shot and epoxy until it weighed nearly 4.5 ounces and I couldn't cram any more into it.

I ran out o' time buildin' this and took it t' t' MTMA launch at their field in Aurora, ya bilge rat, matey, Ohio. Avast, me hearties, me proud beauty! I hoped that after an initial flight on a single D motor, I would attempt t' fly it on a loaded cluster, matey, perhaps beginnin' with outboard A's and then possibly C's dependin' on how t' rocket flew and weather conditions. Well, blow me down! Unfortunately, matey, it didn't work out that way. Arrr! Despite me fears, t' rocket had a stable flight and t' baffle worked perfectly (I was concerned that too much pressure would leak backward through t' baffle wall) and t' recovery system ejected perfectly. Blimey! However, while my Evil Ed chutes had been unfurlin' perfectly, due t' t' cold weather (somewhere betwixt 20 and 30F) t' parachute did not unfurl and came all t' way down in a clump. Well, blow me down! Arrr! T' rocket hit t' frozen ground hard and most o' t' fins were shattered into tiny pieces and t' tip o' t' nosecone was broken off. Well, blow me down! There would be no more flyin' without extensive repairs and certainly no paint.

On t' positive side, ya bilge rat, this was t' first time I have tried this type o' design for t' baffle and it seemed to work well. Arrr! This design turned out nicer lookin' that I had expected and I am still considerin' rebuildin' it. Aye aye! If I do, the next time I will use basswood for fins (or at least take t' time t' use heavier balsa and reinforce them with paper), me hearties, enlarge t' fin set and probably lengthen t' top portion t' add additional stability. Well, blow me down! I really want t' try this as a cluster. Avast, me proud beauty!