Pentagon Lifts Osprey Flight Ban Despite Obscure Messaging On Safety Improvements

The Pentagon officially lifted the months-long ban on flying the V-22 Osprey aircraft Friday even though it has not fully identified the cause of a fatal November crash, according to an announcement and officials.

Preliminary results from an investigation of the fatal November 29 accident near Japan that killed eight special operations airmen suggested an unspecified “materiel failure” instigated the crash, Naval Air Systems Command (NAVAIR), which oversees the Osprey program for each of the services that operate it, said in a statement. The Air Force, Navy and Marine Corps agreed to ground the aircraft on Dec. 6 to review the incident and devise ways to safely operate the platform, but NAVAIR did not say the cause of the materiel failure had been identified.

“NAVAIR remains committed to transparency and safety regarding all V-22 operations,” the command said in the statement, promising to continuously track the platform’s operations “so service members are provided the safest, most reliable aircraft possible.”

“Maintenance and procedural changes have been implemented to address the materiel failure that allow for a safe return to flight,” the statement read. Each of the services will execute individual plans to phase their versions of the Osprey back into flight.

Officials declined to say exactly what component of the Osprey had failed at a briefing Wednesday ahead of the formal announcement, Breaking Defense reported.

“We have high confidence that we understand what component failed, and how it failed. I think what we are still working on is the why and so that is still in the hands of the investigation,” Marine Corps Col. Brian Taylor, the program manager in the Pentagon’s V-22 Joint Program Office, said, according to Breaking Defense.

Safety mitigation efforts include re-training pilots to fly according to procedures revised by NAVAIR as a result of the investigation and changing certain maintenance practices, Taylor said. He was vague on specific mitigation measures.

The Osprey tiltrotor aircraft themselves will not undergo any modifications, Military Times reported.

It could be months before the military’s fleet of 400 Ospreys return to service, Military Times reported. Meanwhile, the investigation into the accident is still underway.

Wreckage of the Air Force’s CV-22 Osprey from the November crash sat at the bottom of the Pacific Ocean for roughly a month, corroding the drive system, Taylor said, according to Military Times. That means officials may never get to the bottom of why the component on that specific rotorcraft failed, although investigators mapped out a “fault tree” to narrow down potential causes.

One of those potential causes involved metal chips found in the aircraft’s propeller rotor gear box, NBC News reported in February.

The Air Force, Navy and Marine Corps, as well as a partner country, operate versions of the V-22 Osprey tiltrotor primarily for transportation and cargo delivery. It is a hybrid aircraft capable of vertical takeoff and landing, like a helicopter, but can travel forward at faster speeds like an airplane.