A small and simple rocket, just 6 oz. without the engine (a J270 bruiser that extends more than half of the way up the body tube). The fin can is a hollow 3D MakerBot print in PLA, laminated with an epoxy rub. She was the first high power launch of the year for the LUNAR Rocketry club (the largest in America), out in the foothills of the Sierras.
The launch control officer gave a proper heads-up warning to the audience that although I have flown this 3D-printed design before, it is very unlikely that the fins will survive the supersonic flutter, and all hell should break loose.
She flew straight as an arrow, popping off the pad so fast, I could not get a single image of her at 4 frames/second (see below).
I ran a RockSim simulation of this rocket before the flight, and since she flew straight, it’s probably pretty accurate: 9k ft. altitude, Mach 1.9, 67 g’s a of peak acceleration! And the fins were in perfect shape after the flight.
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