Burning propellant ejected
The motor was assembled per the included instructions 2 days prior to the flight. No issues were noted during assembly. The case ruptured just below the forward closure, with the forward closure and seal disk being blown clear from the rocket. These were not recovered. The liner and grains were ejected from the case. They were not burning at the time they were ejected, but did re-ignite while in the air. The failure happened shortly after ignition. Approximate burn time was 0.25 seconds.