A fuel leak and a short circuit most likely combined to spark a fire that stalled the engine of an Air Self-Defense Force T-33 training jet in November, causing it to crash in Sayama, Saitama Prefecture, the Defense Agency said Tuesday.
Two crew members died in the crash in which the plane, stationed at the ASDF Iruma base, severed power lines, blacking out 800,000 households for a few hours in Tokyo and Saitama.
“It was an unusual accident (for that model of plane) that occurred due to multiple reasons such as fuel leakage and ignition (problems),” an agency official said.
The agency said it will finalize its investigation and implement safety measures, perhaps within the next couple of days, and will then consider allowing eight other T-33 jets to resume flights.
But the Saitama Prefectural Government and the city of Sayama are concerned about the safety of these old training planes, first deployed in the 1950s, and have asked the agency not to resume T-33 training flights.
The T-33 plane crashed on a riverbank in Sayama on Nov. 22 while on a pilot-training flight. Shortly before the crash, one of the crew reportedly told the base’s control tower by radio, “Smoke is coming into the cockpit.”
The ASDF’s investigation found that the area near the fuel supply equipment was the most badly burned, leading it to believe that fuel had leaked in that area and caught fire.
T-33 jets have been under the process of replacement by T-4 planes since the early 1990s; the existing eight planes are due to be replaced by 2002.
The agency is paying for damage caused by the crash, including compensation related to loss of business hours and computer data during the blackout.