What happened
During a descent toward an airport situated on a mountain ridge, the flight crew of a twin-engine business jet was executing an instrument landing system (ILS) approach. Approximately 24 minutes prior to the accident, the crew began their descent from cruise altitude. While air traffic control provided updated local altimeter settings, evidence suggests the crew failed to update the aircraft's altimeter setting during the descent. This discrepancy was noted by the controller, who observed the aircraft at 5,900 ft msl despite being assigned to maintain at least 6,100 ft msl.
As the aircraft approached the final approach course, the flight guidance system was set to vertical speed (VS) mode. The crew appeared to be navigating via a flight management system-generated course rather than the localizer signal. While the pilots reported having the airport in sight, the aircraft's descent continued below the glideslope. The second-in-command noted the aircraft was below the glideslope and 15 knots above reference speed during the final stages of the approach.
Approximately 30 seconds before the impact, the pilot-in-command disconnected the autopilot. Despite two separate calls from the second-in-command to initiate a go-around following EGPWS warnings, the pilot-in-command did not respond. The aircraft struck rising terrain roughly 300 feet before the runway threshold. The impact and subsequent fire caused the destruction of the aircraft, and all five occupants were killed.
Findings
- The crew did not perform a crosscheck or verification of the altimeter settings during the descent, leading to the aircraft operating at an incorrect altitude.
- The aircraft was likely being flown in a vertical speed mode that maintained a set descent rate regardless of the glideslope position.
- Failure to update the altimeter setting contributed to the aircraft being 200 feet lower than the assigned altitude during the approach.