Casualties unknown

1983-08-09: Aerostar 600 (N7447S) — Pahokee, FL

Pahokee, FL, US

On August 9, 1983, an Aerostar 600 (registration N7447S) was involved in an aviation accident near Pahokee, FL. Investigators recorded the probable cause as: The left engine oil temperature and ignition wires were incorrectly routed within a quarter inch of the turbocharger exhaust, which burned through all wires and grounded out the ignition. The left engine did not feather due to low RPM. 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 1781061362Data APIEditorial standards

An aircraft ditched in Lake Okeechobee after the left engine lost power and emitted smoke from under the instrument panel during climb. Investigation revealed ignition wires burned by turbocharger exhaust.

Event

The aircraft departed Fort Pierce, Florida on a VFR flight to Key West, Florida, and ditched in Lake Okeechobee. While climbing through 5,000 feet, the left engine lost power and started surging. The oil temperature gauge failed, and smoke emerged from under the instrument panel. The pilot reduced power on the left engine and requested vectors to the nearest airport. Believing the engine was producing power, the pilot did not feather the propeller. When he realized the airport could not be reached, he set up for a ditching in the lake.

Ditching and Propeller Feathering

Before touchdown, the pilot cut power and feathered both propellers. The right propeller feathered normally, but the left propeller did not feather.

Engine Inspection

Inspection of the left engine after aircraft recovery showed that the oil temperature and ignition wires had been routed in a bundle of five wires incorrectly placed within a quarter inch of the turbocharger exhaust. The heat burned through all wires, grounding out the ignition system. The left engine did not feather due to low RPM. One hour before the accident, the number 1, 4, 5, and 6 cylinders had been changed, which required removing the engine from the aircraft.

Probable cause

The left engine oil temperature and ignition wires were incorrectly routed within a quarter inch of the turbocharger exhaust, which burned through all wires and grounded out the ignition. The left engine did not feather due to low RPM.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001214X44255. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.