 The U.S. military announced it was grounding all of its Osprey V-22 aircraft. One week after eight Air Force Special Operations Command Service members died in a crash off the coast of Japan, the Air Force. Navy and Marine Corps took the extraordinary step of grounding hundreds of aircraft after a preliminary investigation of last week's crash indicated that a material failure, that something went wrong with the aircraft and not a mistake by the crew led to the deaths, the crash raised new. Questions about the safety of the Osprey, which has been involved in multiple fatal accidents over its relatively short time in service, Japan grounded its fleet of 14 Ospreys after the crash.