US Air Force discloses causes of 2023 CV-22 Osprey accident in Japan
A CV-22 Osprey flying a training mission near San Diego, California. (Photo: US Air Force)
The investigation report pointed to a gearbox failure and management issues as the main causes of the accident.
The US Air Force (USAF) last week released the results of the investigation of the CV-22B Osprey accident in November 2023 in Japan. The incident killed eight crew members and led the Pentagon toward standing down its entire tiltrotor fleet for four months.
The USAF report concluded that multiple causes contributed to the accident including a “catastrophic failure of the left-hand proprotor gearbox”, inadequate risk management and ineffective crew resource management.
After analysing maintenance logs, flight recorder data, briefing materials and inspecting aircraft wreckage, a multi-disciplinary team of subject matter experts found that an issue with the gearbox generated a rapidly cascading failure
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