Casualties unknown

Engine Power Loss During Practice Forced Landing Due to Broken Throttle Cable Support Weld (N7447H)

Mesa, AZ, US

On May 9, 1998, a Piper J3C-65 (registration N7447H) was involved in an aviation accident near Mesa, AZ. Investigators recorded the probable cause as: Failure of a weld in the engine's throttle control support assembly due to inadequate maintenance which was the ultimate responsibility of the owner-pilot. 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 2026-06-10Data APIEditorial standards

A privately owned airplane experienced total engine power loss during a practice forced landing. The pilot landed in a dry wash, shearing off both main landing gear. Investigation revealed a broken weld on a non-Piper throttle cable bracket assembly.

Incident Overview

During a practice forced landing descent, the airplane experienced a total loss of engine power. The pilot, who owned and operated the aircraft, reported that no suitable landing area was within gliding distance. Consequently, the pilot executed a landing in the rough terrain of a dry wash, which resulted in both main landing gear being sheared off.

Post-Accident Examination

After the aircraft was recovered, an examination was conducted. Investigators found that a clamp, which had been welded onto a bracket secured to the engine case, had broken. This clamp and bracket assembly supported the throttle cable. The break occurred at the weld, and when it failed, movement of the cockpit throttle control had no effect on the engine's revolutions per minute (rpm).

Component Details

The pilot described the weld as having been "bad." The component was not a Piper-manufactured part, indicating it was a non-original or aftermarket component. The failure of the weld directly prevented the throttle from controlling engine power, leading to the loss of engine power.

Conclusion

The investigation determined that the engine power loss was caused by a broken weld on the throttle cable support assembly. No other contributing factors were identified in the source.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001211X10144. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.