Investigation Summary
The aircraft, nicknamed Louisiana Fire, was operating a training mission out of Andersen Air Force Base as part of a temporary duty rotation. At approximately 09:55 local time, while positioned 30 nautical miles northwest of Apra Harbor, the aircraft's horizontal stabilizer trim moved to an improper down angle. This configuration induced a steep, rapid descent that left the crew with only 34 seconds to react before impact. Radar data showed the aircraft descending rapidly before disappearing at approximately 2,000 feet. The investigation was severely hampered by the absence of a flight data recorder, as the B-52H was not equipped with one at the time. However, investigators recovered the horizontal stabilizer jackscrew from the ocean floor, which revealed a trim setting of 4.5 to 5 degrees nose-down, providing critical physical evidence for the runaway trim theory. Investigators determined that the combination of a descending left turn and the late recognition of the stabilizer malfunction made recovery nearly impossible, even for an experienced crew.
Final Conclusions
The Air Force Accident Investigation Board (AIB) concluded that the primary cause of the mishap was an improper stabilizer trim setting. While the board could not determine the exact reason for the mispositioning due to a lack of evidence, they identified a system malfunction leading to runaway nose-down trim as the most likely scenario. Contributing factors included the low altitude of the maneuver and the difficulty for the crew to recognize and assess the rapidly developing flight control emergency in time to execute a recovery.
Video Analysis
No video analysis linked for this case file yet.
Systems & Failure Modes
Horizontal Stabilizer Trim
A system used to adjust the pitch of the aircraft; a malfunction led to a runaway nose-down setting that caused an uncontrollable descent.
Interesting Facts
- 01The aircraft was not equipped with a flight data recorder.
- 02The entire mishap sequence, from the start of the trim malfunction to impact, lasted approximately 34 seconds.
- 03The crew included a flight surgeon who was participating in the flyover as the sixth crew member.
- 04The aircraft was part of a rotation replacing B-2 Spirit bombers that had been grounded following a crash in February 2008.
- 05Remains for two of the six crew members, Captain Michael K. Dodson and First Lieutenant Robert D. Gerren, were never recovered.
- 06Evidence from the wreckage suggested at least three crew members attempted to eject, but the aircraft's speed and attitude were outside the survivable ejection envelope.
- 07The crew members were primarily from the 20th and 96th Bomb Squadrons at Barksdale Air Force Base, Louisiana.