The US military’s fleet of Bell-Boeing V-22 Osprey tiltrotors have again been grounded after what the Pentagon describes as a “near-crash” in November.
The incident, which occurred in the Southwest US state of New Mexico, involved an engine failure caused by the breakup of an internal metal component. No fatalities have been reported.
Naval Air Systems Command (NAVAIR), which serves as the airworthiness authority for the Pentagon’s entire Osprey fleet, says the flight stoppage went into effect on 9 December.
The US Navy, US Air Force (USAF) and US Marine Corps (USMC) all operate variants of the Osprey, with the USMC fleet numbering more than 300 examples of the tiltrotor.
The USMC tells FlightGlobal it implemented a 96-hour operational pause for non-essential flight operations starting on 6 December.
”This pause will give us time to determine if any additional measures are necessary to ensure the continued safety and effectiveness of this critical capability.” the service says. ”The Marine Corps remains confident in the safety and effectiveness of the MV-22.”
The latest grounding comes just more than one year after an air force special operations CV-22 crashed off the coast of Japan, killing eight personnel. A subsequent investigation found the cause of that 2023 incident to be a metal fragmentation issue in the aircraft’s left-side prop-rotor gearbox.
The Pentagon grounded the full Osprey fleet for three months after that incident, controversially resuming flight operations without a firm mechanical solution to the issue. In September, the USAF returned its CV-22s to combat status.
USMC MV-22s have been flying non-combat missions since at least April.
NAVAIR commander Vice Admiral Carl Chebi, who recommended the latest pause on V-22 flight operations last week, stated in June that he did not expect a long-term solution to the mechanical problem identified in the Japan crash until 2025.
“We are methodically looking at material and non-material changes that we can make to allow for a full mission set without controls in place,” he told members of Congress in June. “Based on the data that I have today, I’m expecting that this will not occur until mid-2025.”
Temporary measures were instituted to lessen risks of crashes, including limiting flights over water and staying within specified flight times of diversion airfields.
Other flight procedures were also changed, including those specifying how pilots react to cockpit warnings of material failure and metal-chip fragments.
