This was Bruce O'Briens Shadow Composites Raven. 38mm Minimum Diameter airframe. Just large enough for the motor to slide into. I made the motor with a fast burning propellant. Total was about 1,100 Newton seconds. Burn time was ... well, FAST! Bruce wanted to tube launch this rocket, so it's in the gray tube in the middle of the screen. The debris that comes out of the tube is a cardboard 'piston' he made.