The Lockheed Martin F-35A fighter that crashed during routine training exercise reportedly failed to send distress signal before it plunged into the Pacific, Japan's Air Self-Defense Force (ASDF) said Thursday.
The single-seat $126 million jet had a system that would have emitted emergency alert if the pilot ejected from the cockpit with a parachute, the ASDF was quoted as saying by Japan Times.
Radar operators tracking the jet received a training abort message from the lost aircraft before it disappeared about 135 km (84 miles) east of the Misawa Air base in Aomori around 7pm. The fighter was flying with three other aircraft at a distance for an air-to-air combat exercise.
There was no communication from the pilot indicating a problem with the aircraft, according to a report by Reuters.
It is the first crash involving an F-35A aircraft worldwide.
Shortly before it dropped off the radar, the pilot of the aircraft radioed the other three to say he was about to pull out of the drill, but none witnessed the plane crash, according to the ministry.
ASDF investigators have found small sections of the F-35’s wing floating in the sea. It suggests that the advanced aircraft hit the water, but not why it disappeared from radar screens without warning.
“We have not recovered anything that would point to a cause,” an air force official told Reuters as the search continues for the missing pilot.