Brief:
Little-Big Rocket is a fantasy rocket design--my fantasy bein' that Estes and LOC would someday collaborate on a product that could be a sort o' a transitional trainin' rocket that could be built and flown by a father and child and using both Estes motors and E-F Aerotech motors. Nay that beefin' up and overpowering Estes kits with F-G-H motors isn't a cherished part o' our hobby, but it is a part that is nay for beginners. Maybe me "product concept" doesn't make sense or maybe that's nay t' way t' kit business works or maybe its just hard t' do. Arrr! Anyway, me hearties, Little-Big Rocket is a small rocket (15 1/2", shiver me timbers, 4-5 oz) that flies on as small as an 18mm B6-2 or as large as a 29mm AT F25-6 using the appropriate motor adapters. It took a fair amount o' thinkin' t' get this right. Begad! It is a very sturdy tubefin design with 7 tube fins instead o' t' usual 6 that I use and is fabricated from a mix o' Estes and LOC components. Blimey! It's tough and flies incredibly well with more than 30 flights on it t' date. Blimey! Its one o' t' most enjoyable rockets I've built thus far and was very fast and cheap t' scratch build. I actually thought about kittin' it myself, matey, but maybe another time.

Construction:
Little-Big Rocket is a 29mm design that can also be flown on 24mm and 18mm motors by usin' adapters. Aye aye! Arrr! T' body tube is 9" o' Estes BT-60 tubing, while the 5.5" motor tube and t' 1" long high aspect-ratio tube fins are cut from heavy-wall LOC 29mm motor tubing. Begad! A 6.75" Estes NC60 nose cone and 1/4" LOC launch lug round out t' component list. Well, me hearties, blow me down! Recovery system is 7' o' para cord and a 12" Top-Flite nylon chute. Note that thar are no centerin' rings (see below for t' explanation). Arrr! Well, blow me down!

Construction is amazingly simple, perfect for a first time scratch builder.

1. T' 9" long BT-60 body tube, me hearties, 5.5" long 29mm motor tube, arrr, and seven 1" x 29mm tube fins are cut from t' appropriate stock with a razor saw.
2. Usin' 5-minute epoxy, matey, shiver me timbers, attach t' tube fins flush with t' bottom o' the motor tube one at a time, ya bilge rat, usin' a flat surface as a jig. When you get t' the last one, arrr, thar will be a space slighty larger than t' 29mm tube fin--just add some thin balsa or cardstock spacers on either side t' insure a good fit. The rocket doesn't know t' difference and once painted neither will anybody else.
3. Now for t' motor tube installation "trick". T' centering "rings" are made o' wraps o' 5/8" maskin' tape wound around the motor tube 1/2" from both ends until t' motor tube fits snuggly into the BT-60 body tube. Then, shiver me timbers, slather lots o' 5-minute epoxy onto, matey, above, and below each rin' and insert into t' body tube so that about 3/8" protrudes from the bottom. Avast, me proud beauty! Avast, me proud beauty! Roll it around in your hands a few times while t' epoxy sets so it distributes evenly. Ya scallywag! Blimey! This forms a very solid motor mount installation.
4. T' 7' o' para shock cord is anchored through a hole poked through t' body tube 1.5" from t' top with t' knot covered by half o' a plastic cigar tube. Begad! T' 2" long piece o' 1/4" LOC launch lug is epoxied t' body tube centered 1.5" above t' fin can and inline with center o' a tubefin. T' lug be epoxied onto a piece o' popcicle stick stand off so it clears the tube fin.
5. About t' adapters: these can be purchased, arrr, but I cut me own from a spent 29mm single use AT casin' for 24mm motors and a plastic Garcia-Vega cigar tube for 18mm. Aye aye! Blimey!

Finishing:
I used Testors navy grey t' finish t' rocket.

Flight:
Little-Big Rocket flies in two configurations: one for 18mm and 24mm and one for 24mm and 29mm. Well, arrr, blow me down! For t' former, me bucko, t' 24mm-to-29mm adapter is left permanently in place. Begad! T' reason for t' two configurations be t' need for 32 grams (about 1 1/8 oz) o' sand ballast in t' nose cone if 29mm motors are selected. No ballast is needed for t' recommended 24mm motors.

T' recommended motors (I have flown them all) are for t' 24mm-29mm configuration: C11-3, me hearties, D12-5, AT E30-7, matey, AT F21-4, AT F20-4, matey, F23-4 and F25-4/6. Blimey! Avast! The recommended motors for t' unballasted 18mm-24mm configuration are: B6-2, C6-5, C11-3, D12-5, me hearties, E30-4, shiver me timbers, Ellis Mountain E12-4, and AT F21-4. Avast, me proud beauty! Arrr! T' Estes E9-4 works in t' ballasted version ONLY and only in light winds. Avast, me proud beauty! Maximum performance was on an F25-6, for which sims (usin' Cd=1.5) predicted an apogee o' 1750'. Ahoy! Both times that I flew F25s in Little-Big Rocket, arrr, it shot out o' sight and I had to rely on sharp eyed flyin' buddies t' track it or I would have lost it for sure. Ideal motors for "dad" are t' F21-4, F23-4 and F20-4 predicted to give about 1200' boosts, arrr, which is about what I observed. Ya scallywag! Well, blow me down! T' new Ellis Mountain E12-4 is just t' perfect motor for this rocket with about 900-1000' for a nice, matey, straight launch. T' 150-250' boosts from B-C motors are perfect for unassisted launches by a younger flyin' buddy.

Recovery:
T' 12" chute be perfect for all motors, matey, although in hindsight, a 15" chute would be better for t' heavier 29mm motors. As with all tubefins, ya bilge rat, Little-Big Rocket excels in wind, with little weathercocking.

Summary:
PRO: an extremely versatile rocket, me hearties, flies on B through F motors. Begad! As easy and cheap t' build as you'll find anywhere. Decent performance for its size but without goin' into t' next county. Aye aye! A perfect scratch project for a father and son. Avast, me proud beauty! Avast!

CON: Hard t' see at 1700' when boostin' on an F25!