FlightFinder
Check my flight
Casualties unknown

Hard Landing After Engine Failure Due to Exhaust Valve Failure (N6636W)

Henderson, TX, US

On October 12, 1989, a Piper PA-28-140 (registration N6636W) was involved in an aviation accident near Henderson, TX. Investigators recorded the probable cause as: The engine failure was determined to be the result of the failure of the #3 exhaust valve, but the root cause of the valve failure could not be determined metallurgically due to secondary damage to all fracture surfaces. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 2026-07-04Data APIEditorial standards

A hard landing occurred after an engine failure in cruise flight and a forced landing in rough terrain. The failure was caused by a #3 exhaust valve failure; root cause could not be determined due to secondary damage.

Accident Overview

The airplane experienced a hard landing following an engine failure that occurred during cruise flight. The pilot executed a forced landing in rough terrain. The engine failure was attributed to the failure of the #3 exhaust valve. However, metallurgical analysis could not identify the root cause of the valve failure because secondary damage had affected all fracture surfaces.

Additional Details

The pilot had recently purchased the airplane, and the engine was 661 hours past its recommended overhaul time. A service instruction that was critical to replacing the existing valves with heavier-duty valves had not been complied with prior to the sale or the accident. The purchaser was unaware of this service instruction.

Probable cause

The engine failure was determined to be the result of the failure of the #3 exhaust valve, but the root cause of the valve failure could not be determined metallurgically due to secondary damage to all fracture surfaces.
Engine failure

Frequently asked questions

What happened in the 12 Oct 1989 Piper PA-28-140 accident near Henderson, TX?

A hard landing occurred after an engine failure in cruise flight and a forced landing in rough terrain. The failure was caused by a #3 exhaust valve failure; root cause could not be determined due to secondary damage.

What aircraft was involved and where did it happen?

The accident on 12 Oct 1989 involved a Piper PA-28-140, registration N6636W, at Henderson, TX.

What was the probable cause of the accident?

The engine failure was determined to be the result of the failure of the #3 exhaust valve, but the root cause of the valve failure could not be determined metallurgically due to secondary damage to all fracture surfaces.

More accident analyses

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001213X29608. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.