On September 17, 2001, at 2023 central daylight time, a Cessna 210K, N9455M, registered to Air Carriers, Inc., and operated by the commercial pilot, collided with trees off the right side of runway 23 during landing roll following a collapse of the right main landing gear at the Bessemer Airport, in Bessemer, Alabama. The cargo flight was operated under the provisions of Title 14 CFR Part 135 with an IFR flight plan filed. Visual meteorological conditions prevailed at the time of the accident. The pilot was not injured, and the airplane sustained substantial damage. The flight originated in Gainesville, Georgia, at 1930. According to the pilot, the approach and touchdown were normal with the green landing gear light illuminated. During landing roll, the pilot began slowing the airplane and it started drifting to the right. The pilot applied left rudder and brakes, which failed to correct the right drift. The airplane then suddenly banked to the right and departed the runway and impacted trees. Before exiting the airplane, the pilot noticed the green landing gear light was still illuminated. Examination of the airplane found the right main landing gear was collapsed. The horizontal stabilizer, empennage, wings, ailerons, and lower fuselage sustained damage. Additional examination found a faulty down-lock switch in the right main landing gear.