Chubby Boy With FatBoy Booster

Jim Myers's Descon-14 Entry

The ChubbyBoy is a BT-60 downscale of a fatboy. (.625 scale) This project started out as a 7 engine MMX cluster, but I quickly discovered how much of a PITA wiring 7 igniters in those little bitty motors can be!! I am not a fan of Flashpan ignition, so we went to plan B.

I decided to stage and cluster. The ChubbyBoy became a 13 mm 5/8 scale FatBoy, boosted with a 3 x 13 mm Fatboy gap staged booster. The fins on the booster are 100% size fatboy fins.

Upon launch, all three A10-0T lit and it went up QUICK! It staged beautifully (A10-3T in sustainer) and ejected way up there. Rocsim sez 638 ft on this motor combo. My shutter finger was nowhere near quick enough. There was more wind aloft than at ground level, and it drifted away even on that little 10 inch shopping bag chute. We may find it tomorrow, as it is near home.

PDF Engineering Drawing (click here)