The Japan Air Self-Defense Force (JASDF) believes pilot disorientation caused the crash of a Lockheed Martin F-35A on 9 April.
A Reuters report quotes defence minister Takeshi Iwaya as saying that it is “highly likely the pilot was suffering from vertigo or spatial disorientation and wasn’t aware of his condition.”
In addition, no distress call was received from the pilot, nor has the investigation into the crash revealed that he tried to eject.
The crash took place 28 minutes after taking off from Misawa air base in Japan’s northern Aomori prefecture.
In a 21 May press conference, Iwaya said that investigators were relying on data received via the aircraft's Multifunction Advanced Data Link as well as land-based radar tracks to analyze the crash.
Tokyo called off the search for the missing aircraft on 4 June. On 7 June Japanese media reports quoted Iwaya as saying that the remains of the pilot had been recovered.
Most of the aircraft, including the flight data recorder, were not found, and lie on the seafloor about 1,500m underwater. Some parts of the lost jet were recovered, including a heavily damaged portion of the flight data recorder.