Last week's Pentagon decision to ground all V-22 Osprey variants across the military is again raising concerns about the safety of the aircraft in the wake of yet another fatal crash.
An Air Force Special Operations Command CV-22 Osprey crashed during a routine training mission off the Japanese coast Nov. 30, killing eight airmen. A Pentagon spokesperson said Thursday all Ospreys would be grounded out of "an abundance of caution."
In less than two years, 20 service members have been killed in four Osprey crashes, including 5 Camp Pendleton Marines killed in June 2022 when their aircraft crashed in Imperial County.
Marine investigators determined the June 2022 crash was caused by a "hard clutch engagement," a known issue with Ospreys that led to at least two temporary groundings in the past.
The Osprey is a tiltrotor aircraft — not quite a helicopter and not quite an airplane. Its twin propellers are mounted on large rotating nacelles on its wingtips, allowing the craft to take off and land like a helicopter but cruise at speeds like an airplane.
To maintain stability while hovering, a clutch mechanism connects the two propellers so that if one of its two engines fail both propellers will remain under power. But, even under normal operation the clutch mechanism can fail — which can lead to the aircraft rolling out of control.
Dan Grazier, a senior defense policy fellow at the Project on Government Oversight, said the qualities that make the Osprey valuable to the military are the same that make the aircraft more deadly.
"It's a large cargo and troop carrying aircraft," he said. "So a lot of time ... there will be a number of passengers on board. So when a crash happens, it's a higher number of fatalities. It gives the impression that the Osprey is more dangerous than other aircraft."
Three branches currently fly the Osprey — the Air Force, Navy and Marine Corps. The Air Force only uses them for special operations and the Navy is beginning to field them on carriers as part of its next-generation air wing.
Right now, only the aircraft carrier Carl Vinson is deployed with Ospreys and a Naval Air Forces spokesperson in San Diego said the ship has "layers" of redundancies and air wing operations are not affected by the grounding.
It's the Marine Corps that operates the majority of the military's Ospreys and, Grazier said, the branch most impacted.
"Because the Marine Corps built an operating concept around this aircraft, whenever they're grounded ... that creates a huge disruption to Marine Corps operations," Grazier said.
A Pentagon spokesperson said each branch will decide when to resume Osprey flights.
