- The Japanese defence ministry on Monday said it believed the F-35A Lightning II Joint Strike Fighter lost in April occurred after the 41-year-old pilot, Maj. Akinori Hosomi, succumbed to “vertigo or spatial disorientation.”
- The aircraft, following a rapid descent from a high altitude, disappeared from radar on April 9 while flying at speeds of almost 700 mph only 1,000 feet above the Pacific Ocean.
- The pilot, pronounced dead last week, did not send out a distress signal, try to eject, or respond to warnings from the fighter’s proximity sensors, which were presumably alerting him of an imminent collision.
- While the ministry has ruled out a loss of consciousness or any technical problems with the fifth-generation fighter, all of Japan’s F-35s remain grounded while pilots retrain critical skills.
- Japan has officially called off its search for the missing fighter jet, which the defence ministry reports was destroyed in the crash.
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The F-35 that went missing in April crashed after the pilot lost his spatial awareness and slammed the fighter into the Pacific Ocean at nearly 700 mph, the Japanese defence ministry said on Monday, according to multiple reports.
A Japan Air Self-Defence Force, or JASDF, F-35A Joint Strike Fighter piloted by Maj. Akinori Hosomi of the 3rd Air Wing’s 302nd Tactical Fighter Squadron mysteriously vanished from radar on April 9 about 85 miles east of Misawa Air Base.
The US and Japan dispatched military assets to assist in search-and-rescue operations. The US ended its search in May, but the Japanese military kept going until last week.
“We believe it highly likely the pilot was suffering from vertigo or spatial disorientation and wasn’t aware of his condition,” the Japanese Defence Minister Takeshi Iwaya told reporters Monday. “It can affect any pilot regardless of their experience.”
The 41-year-old major had over 3,200 flight hours, including 60 hours on the F-35, at the time of the crash.
The conclusion was reached after careful analysis of the radar and flight-control data as well as conversations with other F-35 pilots.
The pilot did not send out a distress signal indicating that he thought he was in trouble, and there is no indication he tried to eject. Further, there is no evidence the major tried to pull up as the fighter’s onboard proximity warning system, which was presumably alerting him of an imminent collision, Reuters reported.
The Japanese defence ministry has ruled out a loss of consciousness or any problem with the plane as an explanation for the crash. Nonetheless, all Japanese F-35 pilots are being retrained on avoiding spatial disorientation and gravity-induced loss of consciousness. All its stealth fighters are grounded.
The ministry said in a statement that the fifth-generation fighter, following a rapid descent from an altitude of 31,500 feet, was flying 1,000 feet above the ocean’s surface at a speed of about 1,100 kph (683 mph) when the jet inexplicably disappeared from radar, according to Stars and Stripes. The defence ministry explained that the aircraft was destroyed “and parts and fragments scattered across the sea bottom.”
On June 3, Japan called off the search for the missing fighter and the remains of the pilot, who was declared deceased at a press conference on June 7 after it was confirmed that body parts found among wreckage discovered shortly after the accident were those of Maj. Hosomi.
The flight-data recorder was found during a later deep-water search, but the memory was lost, leaving many questions unanswered.
“It is truly regrettable that we lost such an excellent pilot,” Iwaya said late last week. “We truly respect Maj. Hosomi, who was lost while devotedly performing his duty and we extend our heartfelt condolences and offer our deepest sympathies to the family.”
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