Post Burnout Thrust Measurements

: Research has been conducted into the problems of avoiding collision between separated payloads and spent rocket motors due to post burnout thrust and into the problem of contamination of scientific instrumentation due to outgassing of the smoldering insulation. In order to measure this post burnout thrust, a payload instrument module was separated from an instrumented Black Brant VC Rocket in the exoatmosphere. In addition to measuring accelerations and velocities, the spent motor was observed by a TV camera on board the command attitude controlled payload module. Analysis shows that the payload separated cleanly from the vehicle at a relative separation velocity of 2.25 ft/sec (0.69 m/sec). However, the residual thrust of the spent motor overcame this differential, catching up to the payload 37 sec after separation and continuing on a parallel velocity vector at about 3.37 ft/sec (1.03 m/sec).