Accident · 1993-03-31

NTSB case DCA93MA033 · BOEING 747-121 · Part 129

What the record says

Event date: 1993-03-31
Event type: Accident
Highest injury level: No injuries
Aircraft: BOEING 747-121 (N473EV)
Operating rule: Part 129
Operator: Japan Airlines Operator named in NTSB report
Operated by (per NTSB report): JAPAN AIRLINES

Probable cause

THE LATERAL SEPARATION OF THE NO. 2 ENGINE PYLON DUE TO AN ENCOUNTER WITH SEVERE OR POSSIBLY EXTREME TURBULENCE THAT RESULTED IN DYNAMIC MULTI-AXIS LATERAL LOADINGS THAT EXCEEDED THE ULTIMATE LATERAL LOAD-CARRYING CAPABILITY OF THE PYLON, WHICH WAS ALREADY REDUCED BY THE PRESENCE OF THE FATIGUE CRACK NEAR THE FORWARD END OF THE PYLON'S FORWARD FIREWALL WEB.

Source: NTSB case DCA93MA033

Flight crew

Flight-crew details for this event aren't in the NTSB database extract we hold (its coverage starts with 2008 events) — a gap in our data, not an absence of crew.

Facts as the NTSB records them — GroundCheck adds no judgement. Preliminary records may be revised as the investigation proceeds.

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