Accident Details
The aircraft, operated under 14 CFR Part 135 as a cargo flight with two flight crewmembers, impacted a fence and terrain on short final during a visual approach to runway 27. The flight was conducted by a commercial operator.
Crew Duty and Fatigue
In the 24-hour period leading up to the accident, the flightcrew worked approximately 18.75 hours, performing flights listed by the operator as either Part 91 or Part 135, all in the conduct of company business. Of that total, 5.9 hours involved flying conducted under Part 135. The accident flight was intended to pick up repair parts for another company airplane that had received minor damage during a previous flight the crew had piloted within the same 24-hour period. After picking up the parts, the crew planned to return to the operator's home base on the same day, with an estimated flying time of 2 hours and 45 minutes.
The captain stated that he was tired and that neither he nor the first officer had slept at any of the stops made during the period. The captain noted that the company prefers for airplanes to return to their home base. He also stated that the company offers an option for pilots to stay overnight if tired, and he has previously stayed overnight—but only for maintenance-related reasons. The Aeronautical Information Manual notes that acute fatigue affects timing and perceptional field performance.
Probable Cause and Contributing Factors
The official investigation determined the probable cause was the pilot not maintaining clearance from the fence. Contributing factors were the pilot's fatigue and the fence.