Casualties unknown

Skywest Aircraft Overruns Runway After Number 2 Engine Fire (N198SW)

San Diego, CA, US

On May 21, 1997, an Embraer EMB-120 (registration N198SW) was involved in an aviation accident near San Diego, CA. Investigators recorded the probable cause as: The failure of maintenance personnel to allow adequate time for the engine oil to drain back into the engine oil reservoir prior to adding additional oil, thereby overfilling the reservoir, which resulted in an engine fire and subsequent damage to hydraulic… 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 Skywest aircraft overran the runway by 1,300 feet after a total loss of power and fire in the number 2 engine. No injuries occurred. Maintenance had added 2.5 quarts of oil prior to the flight due to difficulty determining oil level.

Incident Overview

A Skywest flight experienced a total loss of power and subsequent fire in the number 2 engine. The crew executed a successful emergency landing, but the aircraft overran the end of the runway by approximately 1,300 feet. No additional damage occurred beyond the overrun, and there were no injuries to passengers or crew.

Maintenance Actions Prior to Flight

Immediately before the accident flight, a maintenance person added 2.5 quarts of oil to the number 2 engine. The mechanic was unable to determine the engine's oil level at that time. No evidence was found of any assembly anomalies during the engine hot section inspection, which had been performed about 2.3 hours prior to the flight.

Engine Fire and Oil Leak

The engine fire resulted from ignition of oil that had leaked across bearing seals. Under overfull operating conditions, oil can back flow into the engine rather than drain overboard from the filler neck.

Inconsistent Maintenance Instructions

The elapsed time between engine shutdown and oil level determination, as specified by Embraer in its Maintenance Manual, was found to be inconsistent with the instructions provided by Pratt & Whitney. The Skywest mechanic may not have allowed adequate elapsed time to permit the oil to drain back into the engine reservoir prior to adding additional oil, potentially resulting in an overfilled tank.

Difficulty in Oil Level Determination

The clear color of the oil, particularly in a new engine, made it difficult to see when determining the oil quantity.

Conclusion

The incident involved an engine fire, emergency landing, and runway overrun. No injuries were reported. The investigation highlighted potential maintenance procedural inconsistencies and challenges in oil level determination.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001208X07943. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.