Midwest Power 9, Princeton, IL, October 29, 2011. My trusty, well-used and awesome-looking (thank you Sirius) Interrogator took it's last (for now) flight on an Aerotech E18. I've assembled the 24mm AT RMS a couple dozen times and feel comfortable with it. But a moment after liftoff the forward closure blew out, leaving the motor case and aft ring on the ground near the pad. The rocket traveled 100 feet or so and landed near the control table, the parachute and Nomex still in the sustainer and the forward closure was on the ground underneath it. You can see from the video that the engine mount was blown out. The sides of the body tube around the mount were torn open. The nose cone appears to separate. I'm guessing this is due to drag because the wadding and parachute did not eject. I'm assuming I made an error in the reload. I suppose it could be bad hardware but the threads on the forward closure look intact. Forgive the video quality; recorded with an iPhone 4s.