FATHOM II STATIC FIRE I
The first static fire of this series was fired on September 16th, 2016. The goal of this static fire was to test a new internal thermal protection system that would prevent a burn through at a grain boundry, as seen during the FATHOM flight.
FATHOM II STATIC FIRE II
The second static fire of this series took place one month later on October 15th, 2016. The team had spent the last month designing and manufacturing a case with better thermal protection in the forward end. Unfortunately we had simply shifted the problem from one end to the other. The second static fire of the series saw a burn through at the aft end of the case. The resulting hole in the case looked almost identical to that of the first static fire.
FATHOM II STATIC FIRE III
A month after our second failure, RPL was back out in the Mojave desert for another attempt. On November 19th 2016, RPL fired the third composite FATHOM II static fire case. The composite case successfully held pressure for the entirety of the burn. This static fire represented a successful qualification test of the composite motorcase, motor design, and nozzle design that would be used on the record breaking flight of FATHOM II.