Synopsis
A certificated airline transport pilot executed a landing on a frozen slough. During the landing roll, the aircraft encountered a dirt clump on the ice, causing a collapse of the right main landing gear and damage to the right wing structure.
Landing and Evasive Maneuver
After touchdown, the pilot noticed a football-sized clump of dirt protruding from the ice ahead of the airplane. He applied full left rudder in an attempt to avoid the obstruction. The nose of the airplane moved approximately 20 degrees to the left, but the aircraft's ground track continued in a straight line. Consequently, the right ski struck the dirt clump.
Damage Assessment
The collision resulted in the collapse of the right main landing gear. The right wing then made contact with the frozen surface. The airplane sustained substantial damage to the fuselage, the right wing leading edge, and the right wing main spar.
Probable Cause
The source does not provide a probable cause.