Burning propellant ejected
One CATO of burning propellant ejected out the top, and somehow the motor kicked itself out of the retainer clip. The rocket was largely unharmed other than a bit of too much heat reaching the parachute which has now been fixed (burned nylon shrouds). The other 3 motors in the pack were fine. The top of the motor's ceramic cap was degraded with exposed black powder visible, so I capped it with masking tape which has worked in the past with a similar looking motor that worked OK. This motor is from the same engine manufacturing code that others have had similar problems with.