What happened
On 6 December 2021, an unmanned MQ-9A, tail number 15-4301, crashed during takeoff operations at Holloman Air Force Base, New Mexico. The aircraft, assigned to the 9th Attack Squadron of the 49th Wing, was performing a mission as part of a Formal Training Unit.
During the takeoff roll on runway 25, the pilot attempted to adjust the flaps. However, the pilot mistakenly manipulated the condition lever instead of the flap lever, pulling it backward and causing an immediate loss of engine power. While the crew attempted an engine restart before the aircraft reached the peak of its flight path, the pilot commanded an increased pitch that led to a stall. The aircraft subsequently impacted the runway and exploded, resulting in the total destruction of the airframe. There were no fatalities or injuries reported during the incident.
The investigation
The investigation conducted by the Air Force examined the sequence of events leading to the loss of power and the subsequent flight path of the aircraft. The board reviewed the technical design of the Ground Control Station (GCS) used to operate the MQ-9A, specifically focusing on the throttle quadrant. Additionally, the board evaluated the proficiency of the pilot regarding Launch and Recovery (L/R) operations and the crew's response to the engine failure.
Findings
- The primary cause of the mishap was the pilot misidentifying the flap lever, which led to the accidental shutdown of the engine via the condition lever.
- A second cause was identified as the pilot undercontrolling the aircraft by commanding an excessive pitch during the approach to a stall.
- The design of the GCS throttle quadrant contributed to the error due to the close proximity of the two levers, a lack of distinct markings or color differentiation, and the absence of a safety guard on the condition lever.
- The pilot's lack of proficiency in Launch and Recovery operations was also a contributing factor, as the crew failed to establish an appropriate glide to maintain airspeed following the engine failure.