What happened
On 16 December 2024, an MQ-9A Reaper, identified by tail number 13-4225, experienced a catastrophic engine failure while operating in the Mediterranean Sea. The aircraft was being operated by the 20th Attack Squadron, with the mission control element located at Whiteman Air Force Base, Missouri.
At approximately 17:00:18 Z, the aircraft's engine torque dropped from normal operating levels to zero within a single second. This sudden loss of thrust caused the aircraft to lose airspeed and begin an uncommanded descent. Although the crew rapidly increased throttle to full power, there was no change in engine torque. During the subsequent 16-minute descent, the crew performed multiple checklists in an attempt to restore thrust.
After detecting metal debris in the engine oil, the pilot shut down the engine, and the crew executed a forced landing into the water. Shortly before impact at 17:23:02 Z, the datalink was lost. The aircraft was not recovered, resulting in a loss of government property valued at approximately $13,154,585. There were no fatalities and no reported injuries.
The investigation
The Accident Investigation Board examined data logs from the Digital Electronic Engine Controller (DEEC) and the Engine Fuel Interface Unit (EFIU). These logs revealed that immediately following the torque loss, both units indicated different but accurate speeds, a condition that only occurs when the propeller has physically decoupled from the engine.
Because the wreckage was unrecoverable, the board could not definitively identify the exact component that initiated the failure, though they analyzed technical reports provided by General Atomics Aeronautical Systems Incorporated (GA-ASI).