Casualties unknown

Crop Duster Crashes After Engine Failure and Oil Spray (N5630G)

Marianna, FL, US

On June 18, 1984, a Cessna A188B (registration N5630G) was involved in an aviation accident near Marianna, FL. Investigators recorded the probable cause as: The cracked crankshaft at the propeller flange, which caused a loss of power and oil leakage onto the windshield. 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 crop duster lost power during an operation when oil sprayed on the windshield, forcing a road landing where the right wing struck a tree due to a cracked crankshaft.

What happened

During a routine crop dusting mission, the aircraft experienced an apparent loss of engine power. Simultaneously, oil was sprayed onto the windshield, significantly impairing visibility for the pilot. When the pilot attempted to apply additional power to recover or maintain altitude, there was no response from the engine.

Faced with this mechanical failure and reduced visibility, the pilot executed a forced landing on a nearby road. During the touchdown and subsequent rollout, the right wing of the aircraft struck a tree, resulting in damage to that section of the airframe.

The investigation

A post-accident examination of the engine revealed significant internal damage. Investigators found that the crankshaft was cracked specifically at the propeller flange. Additionally, evidence confirmed that oil was seeping from this crack, which explains the spray observed on the windshield during the incident.

Findings

The mechanical failure originated from a structural fracture in the engine's crankshaft. The location of the crack at the propeller flange allowed pressurized oil to escape into the engine compartment and subsequently onto the cockpit windshield. This combination of sudden power loss and obscured vision contributed to the forced landing scenario.

Safety message

Regular inspection of engine components, particularly high-stress areas like crankshaft flanges, is critical for detecting early signs of fatigue or cracking before they lead to catastrophic failure.

Probable cause

The cracked crankshaft at the propeller flange, which caused a loss of power and oil leakage onto the windshield.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001214X40036. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.