The US military and Japan grounded all of their Osprey V-22 helicopters a week after eight US Air Force officers died in a crash off the coast of Japan due to a malfunction.
The Air Force said that they will remain grounded until the investigation is complete. However, it did not say how long that might take.
Air Force and Navy officials said they “decided to mitigate risk while the investigation continues”.
Probe on
“Preliminary investigation information indicates a potential materiel failure caused the mishap, but the underlying cause of the failure is unknown at this time,” Air Force Special Operations Command said in a statement on Wednesday (Dec 7).
“The stand down will provide time and space for a thorough investigation to determine causal factors and recommendations to ensure the Air Force CV-22 fleet returns to flight operations,” the statement added.
At the time of the crash, the Osprey was being operated as a training flight from a US Marine Corps air base in Yamaguchi Prefecture and was headed towards Kadena Air Base in Okinawa.
Japan—the only other nation known to operate Ospreys as a helicopter and an aircraft with propellers—has said that a fleet of 14 Ospreys has been grounded as well after the crash.
50 have died in fatal crashes since 2007
The US-made Osprey is a multipurpose aircraft that has dual functionalities. It takes off and lands like a helicopter, but can also move forward and cruise much faster with its rotating propellers, just like an airplane, during flight.
Air Force Special Operations Command has 51 Ospreys, the US Marine Corps flies more than 400, while the US Navy operates 27.
The first Ospreys became operational in 2007 after decades of testing. But since then, more than 50 troops have died either in testing the Osprey or conducting training flights in the aircraft, including 20 deaths in four crashes over the past 20 months.
The latest was last week’s crash where the aircraft, according to eyewitnesses, flipped over and was on fire before crashing offshore.
Six bodies were found of the eight killed in the crash.
In August, a separate model of Osprey crashed during a military exercise in Australia, killing three US Marines and injuring 20 others. The incident is still under investigation.
