The JASDF F-35A pilot, who had only 60 hours flying time in the F-35, gave no indication he was in trouble.
Japan’s air force said on Jun. 10, 2019 “spatial disorientation” likely caused one of its pilots to fly his F-35 stealth fighters into the Pacific Ocean in April, hitting the water at more than 1,100 kph (683 mph).
“We believe it highly likely the pilot was suffering from vertigo or spatial disorientation and wasn’t aware of his condition,” Defence Minister Takeshi Iwaya told a briefing.
“It can affect any pilot regardless of their experience.”
By dismissing mechanical or software problems as a cause for the advanced fighter’s crash, Japan’s assessment is likely to come as a relief to other countries that operate or plan to introduce the jet, including the U.S., Britain and Australia.
Japan, Iwaya said, would increase vertigo training for its pilots, check its remaining F-35s and meet residents living near the base from which they operate, in Misawa, Aomori prefecture, before restarting flights.
The Japan Air Self-Defense Force (JASDF) has yet to recover any intact data from the $126 million aircraft’s flight data recorder to back its assessment, which is based on data and communication received by ground controllers and interviews with other pilots.
The pilot, who had only 60 hours flying time in the F-35, gave no indication he was in trouble and did not try to avoid a collision despite advanced instrumentation and a ground proximity warning system that should have alerted him to pull up.
The JASDF did not find any indication he had attempted to eject.
As we have previously explained, the mishap aircraft, F-35A #79-8705 (construction number AX-05), is the first Japanese-assembled F-35A, and was rolled out in Nagoya on Jun. 5, 2017.
The stealth fighter crashed while on a training flight 135km away from Misawa Air Base. It was flying over the Pacific Ocean then.
According to the Iwaya, five of Japan’s 13 F-35As have been involved in seven emergency landings between June 2017 and January 2019. Two of the incidents involved faults in the plane that later crashed. Four of the planes that experienced problems had been assembled by Mitsubishi Heavy Industries, under a partnership with Lockheed Martin. The other jet was made in the US.
Photo credit: Lockheed Martin