Incident Overview
A pilot conducting an Instrument Landing System (ILS) Distance Measuring Equipment (DME) approach to runway 17L encountered fog during the final stage. The aircraft subsequently disappeared from the view of control tower personnel, and both radar and radio communications were lost.
Search and Discovery
After a search lasting 31 minutes, airport operations personnel located the aircraft over halfway down the runway and approximately 600 feet east of the runway centerline. Examination of the scene revealed no evidence that the aircraft had touched down on the runway surface.
Aircraft Configuration
The aircraft was found configured with the landing gear retracted and the flaps deployed. According to standard missed approach procedures, both flaps and landing gear should be retracted after initiating a missed approach.
Approach Parameters
The decision height for the approach was 6,384 feet mean sea level (200 feet above ground level). The required runway visual range (RVR) for a 14 CFR Part 135 flight to commence and execute the approach was 2,400 feet (1/2 mile). When on the glide slope, the decision height is reached at 0.4 miles from the runway touchdown zone.
Mechanical Examination
An examination of the airplane disclosed no evidence of any mechanical malfunction.
Probable Cause
The official investigation determined the probable cause to be the pilot's failure to follow IFR procedures and maintain the minimum descent altitude (MDA). A related factor was the presence of fog.