This was a 3500 lbf hybrid rocket motor static test fire located about 25 miles north east of Majove in the Antelope Valley in southern california. I was just a spectator to this test, so I don't know very much about it, but what I do know is that it used peroxide and HTPB. The fluxuations within the test are throttling of the motor. Its not any instablility within the combustion. Marshmellows anyone?