Accident Overview
An airline transport pilot was repositioning a Beech C99 turboprop cargo hauler without cargo on a 73-mile trip. The pilot had been flying this route for some time and this was his last trip before upgrading to a larger aircraft and route. He told friends that he would take pictures of the scenic parts of the route on his last trip.
Sequence of Events
Three witnesses reported seeing the airplane flying west at low altitude. Two of the witnesses, local ranchers, observed the airplane enter the White Mountains near Trace Plumas Canyon about 7,000 to 8,000 feet mean sea level (msl). White Mountain rises to 14,246 feet, tapering north to 13,559 feet and south to 11,285 feet msl. The airplane was reported missing and located two days later on White Mountain at about 9,400 feet msl. The company flight planned route passed 15 miles south of the accident site through Westgard Pass, about 7,291 feet msl.
Investigation Findings
Examination of the low-energy impact and subsequent recovery inspection failed to reveal any mechanical issues. The official probable cause was determined to be the pilot's failure to follow procedures and directives and his failure to maintain clearance from mountainous terrain.