The US Marine Corps may ground its fleet of Osprey tilt-rotor aircraft as well as other planes to conduct a safety review following a crash in Australia that killed three Marines, a defense official said Monday.
"We are looking at our options in terms of reviewing safety across the Marine Corps fleet at the moment ... pending an across-the-board safety review," a US defense official told AFP.
US officials are also weighing a request by Japan's new defense minister, who told the US military on Monday of his "many concerns" after it flew an Osprey tilt-rotor aircraft in the country following the crash.
Itsunori Onodera, appointed Thursday as Japan's defense minister, had asked the US to temporarily stop flying the aircraft in his country following the accident.
"We have still many concerns," Onodera said during a meeting with Major General Charles Chiarotti, deputy commander of US Forces in Japan, according to a defence ministry spokesman.
Japanese media said the flight took place on the southern island of Okinawa, where a squadron of Ospreys is stationed at the US Marines' Futenma base.
The Marine Corps did not immediately respond to a request for comment, but Chiarotti told Onodera the flight was necessary for operational reasons and that safety was confirmed, according to Japan's defense ministry.
The MV-22 -- a hybrid helicopter-turboprop with a chequered safety record -- has two engines positioned on fixed wingtips that allow it to land and take off vertically. It can travel much faster than a helicopter.
According to the US official, the Osprey crashed after clipping the back of the USS Green Bay while trying to land on the amphibious transport ship.
The Okinawa-based aircraft which crashed was in Australia as part of a joint military exercise called Talisman Sabre, which has just ended in Queensland state.
There have been a series of deadly incidents, mostly in the United States, involving the aircraft.
In April 2000 19 Marines were killed in an MV-22 crash in Arizona.
Locals on Okinawa have protested at the deployment of Ospreys to Futenma, which sits in the middle of a crowded city.
In December a "controlled landing" of an Osprey just off the Okinawan coast during a training flight sparked local anger. The aircraft broke into pieces but no one was killed.