NAVAIR clears V-22s for return to flight

The US Air Force said the Bell Boeing CV-22B involved in a November 2023 Japan mishap was an aircraft from the 353rd Special Operations Wing. The unit operates its CV-22Bs from Yokota Air Base near Tokyo. (US Air Force)

US Naval Air Systems Command (NAVAIR), which manages the global Bell Boeing V-22 fleet, has cleared the tiltrotor to return to flight following a three-month grounding, the service announced on 8 March.

The grounding was implemented on 6 December 2023, following indications that a 29 November US Air Force (USAF) CV-22 crash in Japan occurred because of a part failure. NAVAIR declined to publicly identify the failed part, citing an ongoing accident investigation.

“We have high confidence that we understand what component failed and how it failed. What we are still working on is the why, and so … it's still in the hands of the investigation,” Colonel Brian Taylor, NAVAIR V-22 programme manager, told reporters on 6 March.

Col Taylor did, however, add that the input quill assembly, part of the drivetrain that translates power from the engine to the proprotor, was not the part responsible for the crash. Input quill assembly failures have caused several incidents including fatal crashes.

NAVAIR is advising changes to maintenance procedures as well as a revision of protocol in certain emergencies; the service declined to further describe these changes.

“The mitigations that we're putting in place address this one particular component and how it operates inside of the aircraft, and put in an extra perimeter of safety around that,” Col Taylor said, declining to elaborate further, citing operational security.