Accident Overview
A commercial pilot reported to air traffic control (ATC) that the engine was losing oil pressure while in cruise flight at flight level 190 (FL190). The pilot requested to deviate to a nearby airport, and ATC cleared the descent to 12,000 feet. The pilot entered instrument meteorological conditions while proceeding to the airport.
Pilot's Report
During the emergency descent, the pilot communicated intentions to the UNICOM operator at the intended airport. When asked about location, the pilot stated being 8 miles east, having lost oil pressure, and expressed hope of not hitting mountains. Search and rescue aircraft responding to the emergency locator transmitter (ELT) signal reported that the mountains were obscured at the time of the accident.
Airplane Location and Condition
The airplane was located 400 feet below the crest of a 9,765-foot mountain. The belly and underside of the fuselage were covered with fresh oil.
Engine Examination
Examination of the engine revealed that a 'B' nut on a braided oil line connecting the oil pump to the turbocharger was loose. A teardown of the engine found no internal evidence of lubrication or thermal distress within the engine.