Adding to a dour year for US naval aviation safety, three sailors are missing after a Grumman C-2A Greyhound crashed in the Philippine Sea on 22 November while on a routine transport flight.

The Navy recovered eight of the 11 sailors onboard the aircraft at 3:23, or about 38min after the twin-engined transport crashed while en route from MCAS Iwakuni to the USS Ronald Reagan. The eight sailors are in good condition while rescue crews continue to search for the other three, the navy says.

The incident adds to a list of fatal crashes recorded by US Navy and Marine Corps aviation forces this year.

In July, the service experienced one of the deadliest aviation accidents in its history when a Marine Forces Reserve-operated Lockheed Martin KC-130T crashed in Mississippi, killing 16 service members.

A month later, a Marine Corps Bell Boeing MV-22 struck the flight deck of an amphibious transport dock before crashing into waters off the coast of East Australia, killing three Marines.

In October, a trainer and instructor pilot flying a T-45 Goshawk died in a crash over Tennessee.

In an effort to grasp the spiraling mishap rate, USMC Commandant Gen Robert Neller ordered a brief aviation stand down in August. As of August, the navy’s Class A mishap rate, which incur either deaths or excessive damage, climbed to 4.56 per 100,000 flight hours since the beginning of fiscal year 2017, according to the Navy Safety Center. USMC aircraft compiled a Class A mishap rate of 3.42 during the same period in fiscal 2016.