What happened
During a GPS-based approach to runway 17, a twin-engine corporate jet struck terrain approximately 439 feet before reaching the runway threshold. The aircraft was performing a right-hand turn at the time of the impact. The flight was operating under instrument meteorological conditions with an overcast ceiling of 500 feet and visibility of 1.75 statute miles in mist. The ambient temperature was recorded at -08 degrees Celsius.
As the aircraft descended through 300 to 400 feet above ground level, the pilot reported that the plane encountered icing conditions. This accumulation caused the windshield to become obscured, making it difficult for the pilot to maintain visual contact with the runway. Rather than initiating the prescribed missed-approach procedure, the pilot chose to continue the landing attempt.
Findings
Post-accident inspections revealed significant ice accumulation on various airframe surfaces, with ice measuring up to 3/8 inch thick on the upper portions of the windscreens. Other surfaces featured ice deposits between 1/4 and 3/8 inch thick. While the windshield bleed air switch was set to the high position and the windshield alcohol system was active, the alcohol reservoir remained full, indicating no recent usage. Ice accumulation on the windshield significantly hindered the pilot's visibility during the final stages of the approach.