On March 13, 1999, a Gulfstream G-IV (registration N411WW) was involved in an aviation accident near Durango, CO. Investigators recorded the probable cause as: The failure of the number four fuel line. Factors were the chaffing of the alternator's electrical wires on the number four fuel line, and the subsequent fire in the number one engine nacelle. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
The crew of a cruising airplane experienced low fuel flow and high temperatures on the left engine, followed by a fire indication. The fire was extinguished and the aircraft landed safely. Post-accident examination revealed chafing between an alternator wire and a fuel line.
Incident Summary
While cruising at 41,000 feet mean sea level, the flight crew observed indications of low fuel flow and low exhaust gas temperature (EGT) on the left engine. Subsequently, the oil temperature and fuel temperature gauges for that engine began to rise. The crew requested a descent clearance. As the captain reduced the throttle setting, the fire warning light for the left engine illuminated. The captain then pulled the left engine fire T-handle, which resulted in the fire light extinguishing. The crew secured the engine and requested that emergency equipment be positioned at the destination airport in Durango. The aircraft landed without further incident.
Post-Accident Findings
Examination of the aircraft after the event revealed fire damage to the lower forward area of the left engine nacelle. Further inspection identified that an electrical wire originating from the engine's alternator had been chafing against the number four fuel line. This chafing was determined to be the source of the fire.