Brief:
I added a booster with gap stagin' for me stock Fat Boy.

Modifications:
T' Fat Boy was built stock. Avast!

For t' Booster, me hearties, t' engine mount was assembled in t' usual manner. Blimey! T' aft centerin' rin' is flush with the tube end. Avast, me proud beauty! 1/4" vent holes were punched in both centerin' rings. T' coupler extends into t' sustainer approximately 1/2" with a pretty snug fit. Aye aye! T' fin pattern was upscaled a bit (the root o' t' fins measures at 3 3/4"). T' fins are surface mounted and cut from 1/8" balsa. A separate launch lug was added t' t' booster to give a little extra guidance.

Construction:
T' parts list:

• One Fat Boy kit
• 5" o' BT-80
• 1" BT 80 coupler
• 2.75" BT-20
• 2 80-20 centerin' rings
• 1/8" launch lug
• 18mm engine block
• 2.75" engine hook
• 1/8" balsa stock

There are absolutely no "gotchas" in buildin' t' Fat Boy itself. Arrr! It is a well known kit after all. Begad! Well, blow me down! The booster be no more difficult t' build than t' original kit. Well, ya bilge rat, blow me down! T' Booster is pretty stoutly built. Blimey! I considered using TTW fins, but given t' tumble recovery o' a booster, shiver me timbers, I think it is much better t' pop a fin on landin' than break it.

Finishing:
Finishin' and paintin' went pretty smoothly. Begad! Arrr! I decided against usin' t' supplied decals as I have this thin' about stickers. Begad! Instead I went with a simple yet dramatic paint scheme.

Flight and Recovery:
First flight was t' single stage Fat Boy on a C6-3. Avast, me proud beauty! Well, blow me down! Nice straight flight and clean recovery on a 14" nylon chute. Begad! Aye aye!

Second flight used t' booster with a C6-0 t' B6-6 combination. Boost be slow and straight, me hearties, matey, stagin' occurred fairly low and t' sustainer took o' like a shot. Well, blow me down! Ahoy! It weathercocked a bit but had a very nice high flight. Arrr! Chute ejection was a bit past apogee but deployed cleanly. Well, blow me down! T' booster popped a fin loose on landing, which was easily repaired. Ya scallywag! T' sustainer made a clean landing.

Third flight used a C6-0 t' B6-4 combination which gave an almost identical flight t' #2. Ejection occured at apogee and both booster and sustainer returned without damage.

Summary:
T' Fat Boy by itself is a fun little rocket, which is suitable t' all kinds o' modification. Begad! Blimey! I be worried that the addition o' a booster would make it t' heavy t' fly on an 18mm engine, but it works very well. Avast, me bucko, me proud beauty! Blimey! Blimey! Blimey! I certainly wouldn't use any booster but t' C6-0 though. Aye aye! Blimey! Blimey! Blimey! Blimey! Blimey! For a small field stagin' demo, I think it's just perfect.

PROs: It's a two stage bird that you don't have t' chase all over t' country side. Begad! Avast! T' gap stagin' has worked flawlessly so far. Well, blow me down! Easy t' build and modify.

CONs: I would like t' have seen 1/8" balsa fins used on t' stock Fat Boy. Aye aye! Aye aye! Sticker decals. Blimey! Blech!