What happened
On the night of 9 April 2010, a CV-22B (TIN 06-0031) was operating as the lead aircraft in a three-ship formation for a routine infiltration mission near Qalat, Afghanistan. The aircraft departed from a forward operating base to reach a designated landing zone (LZ). Although the crew had anticipated favorable weather based on regional forecasts, they encountered an unexpected 17-knot tailwind within 10 nautical miles of their destination.
During the approach to the LZ, the pilot executed a nonstandard profile, initiating deceleration maneuvers approximately half a mile later than planned. While transitioning to helicopter mode, the aircraft was traveling at more than double the intended speed. In the final moments of flight, the aircraft experienced an unanticipated rapid descent and struck the ground 0.23 nautical miles short of the target LZ. The impact occurred at a ground speed of 75 knots with the landing gear down and locked and the nacelles in a nearly vertical configuration.
Following the initial touchdown, the aircraft rolled approximately 45 feet across the sand. The nose gear subsequently collapsed as the aircraft struck a shallow natural drainage ditch, causing it to flip. The impact resulted in the separation of the left wing, which ignited, and the loss of the right wing and tail section. The wreckage eventually came to rest upside down. The incident resulted in 4 fatalities, including the pilot, flight engineer, and two passengers, while the remaining crew and 14 passengers sustained various injuries.
The investigation
The investigation examined the sequence of events leading to the impact and evaluated the environmental and operational conditions. Investigators reviewed weather planning strategies, mission briefings, and aircraft performance data. The board analyzed the flight path, the transition from airplane to helicopter mode, and the impact dynamics. While several mechanical and external factors were considered, including enemy action, engine failure, and various system malfunctions, these were ruled out by the investigation board.
Findings
The investigation identified ten substantially contributing factors that led to the accident. These included inadequate weather planning and a poorly executed approach in low visibility. Environmental challenges, such as a tailwind and a difficult visual environment, played significant roles. Additionally, the crew experienced task saturation, and the mishap copilot was noted to be distracted and influenced by negative transfer from behaviors learned in previous aircraft. The investigation also highlighted the pressure to succeed during the unit's first combat mission of the deployment, an unanticipated high rate of descent, and a loss of engine power.