On January 25, 1998, at 1450 central standard time, a Piper PA-32-300 airplane, N2881D, sustained substantial damage from a fire that erupted while the airplane was holding short of runway 14 for takeoff at the Alexandria Esler Regional Airport, Alexandria, Louisiana. The aircraft was operated by RFB Flying Service of New Orleans, Louisiana, and flown by a private individual under Title 14 CFR Part 91. The commercial pilot and the sole passenger were not injured. Visual meteorological conditions prevailed for the planned cross country flight and a flight plan was not filed. The flight was originating at the time of the accident. During a personal telephone interview, conducted by the investigator-in-charge (IIC), the operator reported that the flight departed New Orleans, Louisiana, earlier that day for Alexandria. The aircraft was owned by a private individual and leased to RFB Flying Service who rented the airplane to the pilot. Air Traffic Control personnel reported that the airplane taxied "fast" for approximately 2 miles (due to airport construction) to runway 14 for a VFR departure. The airplane was holding short of the runway when the controller observed smoke coming from the lower part of the aircraft and advised the pilot. The pilot reported that he had smoke in the cockpit and that he and the passenger exited the aircraft through the cockpit door. Subsequently the fire consumed the cockpit and lower portions of the aircraft. FAA inspectors examined the airplane and found structural fire damage to the wings, gear, and braking system. The emergency braking system was found in the "OFF" position. Fire damage precluded a determination of the cause of the braking system fire. A review of the maintenance records by the IIC revealed that the brake linings were replaced on July 16, 1997. The last 100 hour inspection was performed on October 10, 1997.