What happened
During the final approach, the pilot reported that the airplane pitched down immediately after crossing the runway threshold and extending the flaps to 25 degrees. In an attempt to recover, the pilot released the flaps and increased power; however, the aircraft became essentially uncontrollable. Before making contact with the ground, the pilot reduced power and retracted the flaps. The aircraft struck the runway on the centerline and slid for approximately 1,000 feet before coming to a complete stop.
The investigation
An examination of the wreckage showed heavy impact damage to the wings, engines, and the forward fuselage. Investigators also observed approximately one-half inch of rime ice adhering to the leading edges of both the left and right horizontal stabilizers, as well as along the leading edge of the vertical stabilizer.