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LAX91FA334

1991-07-28 · RUBIDOUX, California, United States · Fatal · 1 aircraft · Status: Completed

Airport RIR

Aircraft involved

Probable cause & findings

THE MECHANIC'S IMPROPER INSTALLATION OF THE MAGNETOS AND THE PILOT'S FAILURE TO MAINTAIN FLYING SPEED. FACTORS RELATED TO THIS ACCIDENT ARE THE PILOT'S INADVERTENT STALL AND THE RESIDENTIAL AREA.

Factual narrative

THE PILOT WAS DEPARTING THE AIRPORT ON A LOCAL VFR MAINTENANCE TEST FLIGHT. THE AIRPORT IS SITUATED IN A HIGHLY CONGESTED AREA WITH A TREE LINE AT THE END OF THE RUNWAY. THE AIRPLANE HAD JUST BEEN RESTORED AND THIS WAS THE FIRST FLIGHT IN 19 YEARS. WITNESSES REPORTED THAT SHORTLY AFTER LIFT-OFF THE AIRPLANE'S ENGINE BEGAN TO BACKFIRE AND THEN QUIT. THE AIRPLANE ENTERED INTO A RIGHT BANK, STALLED AND CRASHED INTO A RESIDENCE'S BACKYARD. THE INVESTIGATION REVEALED THAT BOTH MAGNETO HOLD-DOWN NUTS WERE LOOSE AND THE ENGINE TIMING COULD NOT BE DETERMINED. THE LEFT MAGNETO WOULD ONLY PRODUCE SPARK IN ONE LEAD AND THE RIGHT MAGNETO WOULD NOT FIRE WHEN THEIR RESPECTIVE DRIVE WERE HAND ROTATED. THE MAGNETOS OPERATED NORMALLY WHEN TESTED WITHOUT THE ENGINE'S IGNITION HARNESS. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12

Verbatim from NTSB's published report. Source file NTSB_1991_LAX91FA334.txt. Findings + structured fields enriched from FAA avall.mdb. Full investigation docket on data.ntsb.gov ↗.

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