On September 18, 1997, about 1330 Alaska daylight time, a tundra tire equipped Piper PA-18, N2355H, crashed during landing at the Coldfoot Airport, Coldfoot, Alaska. The airplane was being operated as a visual flight rules (VFR) cross-country government flight under Title 14 CFR Part 91 when the accident occurred. The airplane, operated by the State of Alaska, Department of Public Safety, Division of Fish and Wildlife Protection, sustained substantial damage. The certificated private pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed. VFR flight following procedures were in effect. The flight originated at the Fairbanks International Airport, Fairbanks, Alaska, about 1030. The operator reported the airplane had just received a 100 hour inspection from a contract maintenance facility in Fairbanks, Alaska, and the pilot was returning to his post in Coldfoot. During the flight, the pilot utilized a short section of tubing to direct heater air to his feet. The pilot landed on runway 19 at Coldfoot. When the airplane touched down, the pilot discovered the brakes were locked. The tires skidded on the gravel surface of the runway, and the left wing struck the ground. The pilot indicated the brakes remained locked for about 2 hours after the accident. At that time, the wheels turned normally. The airplane manufacturer reported the airplane utilizes a separate master brake cylinder/brake pedal assembly for each main wheel brake. The master cylinder/brake pedals are located on the cockpit floor, adjacent to the rudder pedals. The brake cylinders are normally serviced by adding hydraulic brake fluid through a small cap on the top of each cylinder. Maintenance personnel from the operator reported that over-servicing of the brake cylinders, and heating of the cylinder assembly produced a locked brake condition.