A Japanese F-35A Lightning II stealth fighter jet with one pilot on board disappeared from radar while flying over the Pacific on Tuesday night, the defense ministry said.
The single-engine jet operated by the Japan Air Self-Defense Force (JASDF) was on a training flight with three other F-35s when the contact was lost.
The planes, based at Misawa Air Base on the northern tip of the main Japanese island of Honshu, were about 135 kilometers (84 miles) off the east coast of Aomori prefecture when contact was lost, according to defense ministry officials.
The disappearance prompted Japan’s military to ground its remaining fleet of the U.S.-made warplanes.
The defense ministry spokeswoman said Japan’s forces were “still trying to search for the aircraft. The Japan Self-Defence Forces (JSDF) and the Coast Guard dispatched vessels to carry out rescue operations, national broadcaster NHK said.
Japan’s first squadron of the $100 million fighter jets went operational just 11 days ago, with about a dozen of the jets forming the 302nd Squadron at the Misawa Air Base.
The Japanese jet would be the second lost to an accident. A U.S. Marine Corps F-35B crashed in Beaufort, South Carolina, in late September last year. U.S. defense officials said a faulty fuel tube was the likely cause, and all F-35s operated by the United States and its allies were temporarily grounded for inspection.