38mm carbon fibre mach madness rocket, flown t' 18000ft on an Aerotech J570. Ahoy! Max velocity was 2970ft/sec, shiver me timbers, or 2025mph. Avast! Recovered undamaged 2km from t' launch site. Blimey! Mach 1 was broken less than 100ft off t' pad, matey, max velocity reached 2.0 seconds after launch. Begad! 112G's were pulled at liftoff.