Casualties unknown

Engine Failure During Aerial Application Due to Connecting Rod Fracture (N5695J)

Pocatello, ID, US

On June 17, 1985, a Cessna 188A (registration N5695J) was involved in an aviation accident near Pocatello, ID. Investigators recorded the probable cause as: The engine's number two connecting rod broke and penetrated the crankcase due to the engine exceeding its recommended 1200-hour overhaul time, having accumulated 2174 hours without overhaul. 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

An aircraft engine failed during aerial application operations. Investigation revealed a broken number two connecting rod that penetrated the crankcase, attributed to exceeding recommended overhaul intervals.

What happened

The incident occurred while the aircraft was engaged in aerial application duties. During this phase of operation, the engine abruptly ceased functioning. The pilot was unable to continue the mission due to the sudden loss of power.

The investigation

Following the event, a detailed teardown of the engine was conducted to determine the root cause of the failure. Examination of the internal components revealed significant mechanical damage. Specifically, the number two connecting rod had fractured. The force of the breakage caused the component to penetrate and exit through the top of the crankcase.

Findings

Review of the maintenance records indicated that the engine had accumulated a total time of 2174 hours since its last overhaul. This duration significantly exceeded the manufacturer's recommended overhaul interval, which is set at 1200 hours. The failure was directly linked to the engine operating beyond its serviceable life.

Safety message

Adherence to recommended overhaul times is critical for engine reliability. Operating an engine well past its designated maintenance intervals increases the risk of catastrophic mechanical failure.

Probable cause

The engine's number two connecting rod broke and penetrated the crankcase due to the engine exceeding its recommended 1200-hour overhaul time, having accumulated 2174 hours without overhaul.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001214X36927. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.