Incident Overview
Radar data from an instrument landing system (ILS) approach to Runway 5 at Coeur d'Alene Airport indicates that the airplane was flying well above the expected altitude throughout the procedure. According to standard approach profiles, an aircraft would cross the outer marker (OM) at 4,039 feet and the middle marker (MM) at 2,535 feet mean sea level (MSL). However, the airplane's altitude in the vicinity of the VOR, the middle marker, and the airport remained between 4,900 and 5,100 feet MSL.
Descent and Collision
After passing the airport, the airplane continued to descend and subsequently collided with the peak of a mountain located approximately 7 miles from the airport. The impact occurred 2 feet below the summit, which has an elevation of 3,395 feet MSL. The collision resulted in damage to the aircraft. No further details regarding occupants, injuries, or the specific type of aircraft were provided in the source.
Context
The flight was conducting an ILS approach, a precision approach procedure that provides lateral and vertical guidance. The significant altitude deviation from the expected descent profile suggests the airplane was not in a normal approach configuration. However, the source does not specify the cause of the deviation or the events leading to the collision.