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Exposed: How a Japanese F-35 Crashed During a Combat Exercise
The fatal crash of a Japanese Air Self Defense Forces (JASDF) F-35A in April 2019 lead to much discussion about the future of the program. Tons of speculation as to whether the crash was due to aircraft error, pilot error, or other factors occurred. Now, fewer than two months later, the JASDF has released an official report as to the cause of the crash. The report provides a rough chronology of the crash, detailing the altitude and actions of the aircraft before the crash as well as providing a useful visualization of the aircraft’s maneuvers.
The crash occurred during an air combat training exercise, following a controlled left descending turn. The turn was initiated to gain space from another aircraft in the combat area, but halfway down the pilot radioed to “Knock it off,” signaling an end to the training. Past that point, the descent rate increased until the crash.
At the time of the last “Knock it off” transmission, the pilot’s voice was calm and not strained, and the aircraft didn’t diverge significantly from a straight path following that transmission. As a result, the report concludes that its unlikely that the pilot lost consciousness or control due to G-forces during this period.
The report also states that the pilot did not suffer any mechanical difficulties during the initial descent and that no recover maneuver was attempted. The second phase of descent after the “Knock it off” transmission was at a rate only slightly higher than that of the original phase of descent.