What happened
On a night approach into Bristol-Tr-Cities Airport during snow showers, an aircraft struck the slope of Mt Holston, located approximately 15 miles from the threshold of runway 27. The impact and subsequent fire resulted in ten fatalities with no survivors.
The flight originated from Nashville, Tennessee, operating with a malfunctioning radio compass. While the aircraft was cleared to fly via the Green 5 low-frequency airway, the navigation facilities for this route were not utilized during the flight. As the plane reached the Tri-Cities region, it had drifted east of its planned path and incorrectly identified the specific reporting point required to begin an ILS approach.
During the instrument approach, the crew missed the outer marker. The descent continued under instrument meteorological conditions without the use of VOR facilities, which could have helped verify the aircraft's position. Consequently, the pilot flew 15 miles past the outer marker and descended into terrain that was too low to be cleared.
Findings
Investigation revealed that the pilot failed to correctly identify the Gray intersection. Furthermore, the decision was made to proceed with an ILS approach in a manner that violated both regulatory standards and company operating procedures.