On March 5, 1974, a NAMC YS-11 (registration N208PA) operated by Pacific Southwest Airlines - PSA was involved in an aviation accident near Borrego Springs, United States of America in flight. No fatalities were reported. Investigators recorded the probable cause as: The dual engine failure was caused by insufficient maintenance and inspection protocols combined with a malfunction in the propeller system. This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A); 1 related events involving the same aircraft type or operator are linked below.
A training flight departing from San Diego resulted in a belly landing and aircraft destruction after both engines failed and caught fire.
What happened
A training mission originated from San Diego Airport with four pilots on board. During the flight, the crew performed maneuvers to simulate stall conditions, at which point both engines ceased to respond properly. Shortly after this loss of power, a fire developed in both engines. In response to the emergency, the crew attempted an unplanned landing in a desert region. The aircraft type (unspecified) completed a belly landing approximately 8.8 miles east of Borrego Springs. Although the aircraft was destroyed by the subsequent flames, all four crew members managed to exit the wreckage without any injuries.
Findings
Investigations into the incident identified that the primary cause was a dual engine failure during flight. This failure was attributed to inadequate maintenance and inspection procedures. Additional contributing factors included:
Malfunction of the propeller system, specifically an inoperative hi stop hub connecting switch
Improper operation of the powerplant
Presence of excessive temperatures
Insufficient supervision of the flight operations
Probable cause
The dual engine failure was caused by insufficient maintenance and inspection protocols combined with a malfunction in the propeller system.