The official investigation into the crash by the Interstate Aviation Committee revealed that whilst snow was removed from the aircraft exterior, de-icing fluid was not applied. The crew did not ask for permission to enter the taxiway, which was done at too high a speed for the icy conditions, and the flaps were set to 11 degrees, instead of 20 degrees.
An official investigation by the Interstate Aviation Committee concluded that despite removing snow from the aircraft's exterior, de-icing fluid was not used. The crew entered the taxiway without permission at a speed that was too high for the icy conditions, and the flaps were set to an incorrect angle of 11 degrees instead of the recommended 20 degrees.