Incident Summary
A medical evacuation flight, after refueling in Denver, was diverted from its original destination of Aspen to Eagle in order to enplane a patient. The instrument flight rules (IFR) segment to Eagle was uneventful, with radar service terminated after the controller cleared the flight for the LDA-A approach to Eagle Airport, which has an inbound course of 239°. The last radio contact occurred when the crew responded to Eagle radio's request for a base report, stating "we're 8 to 10 out and it's clear ahead." The aircraft subsequently collided with a mountaintop at 8,022 feet mean sea level, located at a bearing of 298° and 3.88 miles from the airport, while in the approach configuration.
Accident Sequence
The safety board believes the flight was circling to land on runway 07. The dark night conditions prevented the required visual lookout to avoid terrain obstructions. The Jeppesen approach charts used by the flightcrew did not accurately depict terrain obstructions within the 5-mile radius of the airport, as stipulated by their legend. The safety board believes this could have misled the flightcrew.
Investigation and Probable Cause
The official probable cause findings identify the occurrence as an in-flight collision with terrain during the approach phase of operation, specifically in the VFR pattern on base leg or base to final. Findings include: the pilot in command conducted an improper planned approach, failed to maintain proper altitude, and disregarded the minimum descent altitude. Contributing factors were the mountainous terrain, the pilot's inadequate preflight planning, lack of familiarity with the geographic area, dark night conditions, the inability to visually lookout, and inaccurate approach charts.