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DEN90LA054

1990-02-03 · PROVO, Utah, United States · None · 1 aircraft · Status: Completed

Airport PVU

N21492 has since been reassigned. It is now registered to a different aircraft (CESSNA P210N), which was not involved in this event.

Aircraft involved

Probable cause & findings

IMPROPER INSTALLATION BY MAINTENANCE PERSONNEL AND FATIGUE FAILURE AND LEAKAGE OF THE LEFT INTERMEDIATE EXHAUST PIPE, WHICH RESULTED IN AN IN-FLIGHT FIRE IN THE ENGINE COMPARTMENT. CONTRIBUTING FACTORS WERE: INADEQUATE SERVICE BULLETIN PROVIDED BY THE MANUFACTURER AND INSUFFICIENT STANDARDS PROVIDED BY THE (FAA) AIRWORTHINESS DIRECTIVE.

Factual narrative

DURING FLT, THE PLT NOTED A DROP IN MANIFOLD PRESSURE & DECIDED TO MAKE A PRECAUTIONARY LANDING. WHILE ON A BASE LEG TO LAND, HEAVY SMOKE & FUMES FILLED THE CABIN & REQUIRED THE PLT TO LOOK OUT THE SIDE VENT WINDOW TO COMPLETE THE LANDING. AFTER THE AIRCRAFT STOPPED ON THE RUNWAY, A FIRE IN THE ENGINE COMPARTMENT WAS EXTINGUISHED. AN EXAM REVEALED THAT THE LEFT INTERMEDIATE EXHAUST PIPE (LYCOMING PART NO: LW-15811) HAD PARTIALLY SEPARATED AT THE FLANGE. THE ENGINE CROSSOVER EXHAUST ASSEMBLY HAD BEEN MODIFIED IN ACCORDANCE WITH AD 89-12-04 & TEXTRON LYCOMING SERVICE BULLETIN #484, WHICH WERE INTENDED TO PREVENT THIS KIND OF FAILURE/SEPARATION. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12

Verbatim from NTSB's published report. Source file NTSB_1990_DEN90LA054.txt. Findings + structured fields enriched from FAA avall.mdb. Full investigation docket on data.ntsb.gov ↗.

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Related research

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