An Air Force investigation into the fatal CV-22B Osprey crash off Japan last November concluded that the crash was caused by a catastrophic failure of a pinion gear in the proprotor gearbox and the pilot's decision to ignore multiple warnings to land. This tragic incident resulted in the deaths of eight crew members and led to a temporary grounding of the Osprey fleet. The investigation criticized the Pentagon for not sharing crucial safety data that could have warned the crew about the severity of the risk. Despite the confidence that the pinion gear failure was the cause, the exact reason for its failure remains unknown. Additionally, the pilot's commitment to completing the mission was noted as a contributing factor to the crash.