If this is the one I'm thinking of, replacing the motor means major surgery on a thin plastic fuse. The motor may have been something between a pager motor and maybe a 180 sized brushed motor. Main thing I remember from it was that when I had given up on it, I was trying to get the motor out by cutting the molded plastic fuse apart, slipped, and put a new Xacto #11 under the nail of my left index finger.

I also had the newer F-8 Crusader control liner that doesn't fly any better, but does reliably drop a small bomb. Best part of it is the bomb release really does work.