Background
The flight was an on-demand charter operation intended to pick up both passengers and cargo. However, a landing gear problem necessitated the dispatch of another aircraft carrying a mechanic. That second aircraft returned with the passengers, leaving the accident airplane at the original location.
Repair and Subsequent Departure
The mechanic repaired the landing gear issue. At a later time, the accident aircraft departed with only the cargo on board. Notably, the flight was not operated under a flight plan.
Flight and Conditions
According to reports from the other company aircraft, instrument meteorological conditions (IMC) prevailed from 7,000 feet MSL to 12,500 feet MSL. The accident aircraft continued its journey under these conditions.
Discovery
The aircraft was subsequently found on the side of Mount Torbert at an elevation of 10,570 feet. Inside the cockpit, the pilot-in-command was located in the right pilot seat with a non-aviation related book in his lap. The mechanic was found in the left pilot seat, holding a World Aeronautical Chart, CD-11, open on his lap. The mechanic held a commercial pilot certificate but lacked an instrument rating.
Investigation Findings
The investigation revealed weaknesses in company operations. No probable cause was explicitly stated in the source material.