Flight 123 Crash

On August 12th, 1985 Flight JL 123 crashed into Mount Osutaka, 100km west of Huneda airport in Tokyo.

The crash was a result of incorrect maintenance.

The aircraft had undergone fuselage repair seven years earlier which had used two doubler plates instead of one, and over a small section of splice the rivets had bound only one of them.

The fault was unable to be detected by a visual inspection, and the reduced resistance to fatigue was not noticed until the incident investigation.


Incorrect maintenance procedures also caused the crash of Flight 191 takeoff crash through increased fatigue.