Accident Summary
On 14 July 2022, an MQ-9A unmanned aircraft, tail number 17-4341, operated by the 489th Attack Squadron Launch and Recovery Element (LRE) and the 50th Attack Squadron Mission Control Element (MCE), crashed in the United States European Command Area of Responsibility. The mishap resulted in no injuries or fatalities. The loss of government property was valued at $14,600,000, and minimal damage to civilian property was reported.
Sequence of Events
The aircraft took off under LRE control and was handed to the MCE. While under MCE control, the aircraft experienced two faults: a failure in the aircraft control network subsystem to transmit, which led to a fault with the electrical engine control system. The MCE executed the appropriate checklists, requiring a "land as soon as possible" action. The MCE returned control to the LRE. The mishap crew (MC), consisting of the mishap pilot (MP) and mishap sensor operator (MSO), misdiagnosed the issue as "stuck torque" and concluded an engine-out approach was necessary. At the initial approach point, the MP moved the condition lever to the full aft position, cutting off fuel and shutting down the engine. The Heads Down Display indicated the engine was still running. Believing the engine was operational, the MC attempted a go-around. Due to the lack of thrust from the shutdown engine, the aircraft could not maintain flight and experienced controlled flight into terrain while under the MP's control.
Investigation Findings
The Abbreviated Accident Investigation Board President determined the cause of the mishap was pilot error, resulting from channelized attention and basic airmanship. The MP focused excessively on the "stuck torque" indications, leading to an incorrect diagnosis of Engine Throttle Control Failure. This misdiagnosis directly led to the MP's actions and the subsequent controlled flight into terrain during the unsuccessful engine-out landing recovery. Additionally, three factors substantially contributed to the mishap: the MC's incorrect diagnosis of emergency procedures, failure to perform a controllability check, and the MC's Commander's insufficient involvement during the incident.