A Marine Corps investigation has concluded that an MV-22 Osprey crashed on take-off last year in the Arabian Sea because it was accidentally started in maintenance mode. As a result of the investigation into the Oct 1, 2014 crash, the Marine Corps and Naval Air Systems Command took quick action to adjust the aircraft and its flight manuals.
“A week after the crash, an order to revise the manuals in pen and ink was issued. Within two weeks, a naval message warned the entire MV-22 community about operating the aircraft in maintenance mode,” according to the San Diego Union-Tribune.
Also, a fleet-wide MV-22 software update was implemented to allow full power in the event an aircraft takes off when in maintenance configuration, according to a Program Manager.
One of the commanding officers making recommendations in this case said that while the crew was not willfully negligent in executing their duties leading up to this mishap, he does believe “strict adherence to naval operating procedures and checklists could have prevented the accident.”
That officer also targeted the design of the aircraft, as well as naval air safety officials, saying: “It is inexplicable that an aircraft systems design would allow a crew to take an aircraft flying with a potential degradation in engine power of 20 percent without providing a caution or warning alerting them of the situation. This poor design, and the fact there is no documentation to warn the crew of this design in naval operating procedures is a contributing factor to this mishap.”
According to a report obtained by the San Diego Union-Tribune, the investigation into the accident also “cited the pilots and crew for not strictly following start-up procedures that could have prevented the deadly mishap, a lack of warning to them about newly discovered hazards of flying the Osprey in maintenance mode, and the potential fatigue of the sergeant who unintentionally initiated the wrong system setting.”
That senior crew chief was also a new father, his wife had given birth to their third child two weeks earlier. After five weeks on the night shift he wasn’t as rejuvenated as usual, according to the article.
The investigation revealed that when started in maintenance mode, the exhaust deflector that “protects the avionics from overheating remained on, reducing engine power by about 20 percent.”
A Marine Helicopter Squadron issued a hazard report about the issue in April 2014. “But the crew of the Osprey that crashed in October had not been briefed on it by their squadron or Naval Air Systems Command. The aircraft controls didn’t warn them they were about to take off in maintenance mode, nor did their flight manuals explain the dangers,” according to the report.
“After starting the engines, the pilots thought it odd that both hung up for about 15 seconds before spooling normally. They also discussed the fact that the exhaust deflector was set to ON instead of AUTO as usual. But the aircraft seemed otherwise to operate normally, so they assumed a harmless software update was to blame,” the article said.
According to the report, the co-pilot lifted the aircraft into a 15-foot hover and as the Osprey slid left over the edge of the deck, it plunged toward the sea.
The 70-foot drop from deck-level slammed Cpl. Jordan Spears, a crew chief, flat. “We are ingesting saltwater and we will continue to lose power to salt incrustation,” the sergeant onboard advised.
The crew chiefs were ordered to ditch. They slipped into the water out the back ramp without employing the life raft. They didn’t have time before the aircraft sank, said the report.
Cpl. Spears, bailed out and was lost at sea after the Osprey hit the water. He died at age 21. Spears was the first American killed in action during the campaign against the Islamic State group of militants in Iraq and Syria. This was his first deployment.
After making several adjustments, the pilots fought to pull the Osprey out of the water and managed to get it back in the air, and flew it back to their ship.
But the MV-22, was submerged about four feet at one point in corrosive saltwater. It required replacement engines and other parts costing more than $1.5 million.