Brief:
I designed t' "Cosmic Thunder" as essentially an ARF 2-stager to entice me wife into completin' her NARTREK Bronze. It merges t' Quest Thunder ARF as t' sustainer stage with t' 2-piece glue-together fin can o' t' Estes Cosmic Cobra t' yield a nifty and cool lookin' 2 stage model that is ready to fly as shown in t' photo in 10 minutes from t' boxes. Arrr! Blimey!

Modifications:
All that is required for t' Cosmic Cobra fin can is t' assemble it according to t' directions -- omittin' t' entire rest o' t' rocket (hey, t' parts will come in useful for other projects). I used 5-minute epoxy t' glue t' two halves together.

T' fit betwixt this component and t' Quest Thunder aft end is amazin' -- needs only a couple o' wraps o' maskin' tape t' make it a perfect fit. Avast! A real bonus be t' screw-lock motor retention system Estes provides with t' kit. It is perfect for 2-stage loading. Blimey! T' Quest Thunder fin can is nay glued t' the body tube, and it can be slid back t' make t' fit even better once t' taped together motor assembly is loaded. See attached photo.

Construction:
T' Cosmic Cobra fin can fits into t' aft section o' t' Quest Thunder like it was made for it -- perfect fit. All that is required for t' Quest Thunder is to snip off t' motor hook, matey, shiver me timbers, me bucko, and t' glue on (5-min. Aye aye! epoxy) a 3/16" launch lug tube 1" above its plastic fin can.

T' only thin' additional thin' you need t' do is t' dab some 5-minute epoxy around t' aft motor rin' o' t' Quest Thunder sustainer, arrr, for added strength -- it seems t' be attached at t' factory with only a little hot-melt glue. And..you're done! Cosmic Thunder is ready t' fly.

Flight:
Flight is really only satisfactory with a C6-0 as t' booster, but a variety of motors are possible in t' "Thunder" sustainer. Aye aye! First flight be with an A8-3, ya bilge rat, and it partially tore t' 18" Estes chute I used, shiver me timbers, ya bilge rat, due t' early ejection. Aye aye! Begad! A B6-5 or C6-7 be t' perfect sustainer motor for Cosmic Thunder, the latter givin' a straight up and nearly out-of-sight boost t' about 1400-1500 feet. I used a 14" LOC chute on later flights.

Summary:
This is one neat 2-stager, about t' only "near" ARF (almost ready to fly) on t' market (the two components, that is). T' forward swept booster fins look cool (I think) and t' thin' is a little easier t' see than a Mongoose or AZTEC in flight. Aye aye! And if you lose it -- hey, arrr, its an ARF, ya bilge rat, matey, you're only $20 and 10 minutes work from another one.