On June 3, 2006, about 1400 Alaska daylight time, a Piper PA-18-150 airplane, N7452J, sustained substantial damage when it ground-looped during taxi at the Birchwood Airport, Birchwood, Alaska. The airplane was being operated by the pilot as a visual flight rules (VFR) personal cross-country flight under Title 14, CFR Part 91, when the accident occurred. The private certificated pilot and sole passenger were not injured. Visual meteorological conditions prevailed, and no flight plan was filed. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on June 20, a spokesperson for the pilot, who said she was calling at the pilot's request, said the pilot told her he had serviced the airplane's brakes prior to takeoff. She also said he told her the left brake was sticking, and that during the takeoff roll the left brake froze. According to the spokesperson, the pilot said the airplane veered off the left side of the runway, encountered a ditch, and ground-looped. During a telephone conversation with the NTSB IIC on June 15, the mechanic repairing the airplane said the airplane sustained damage to the wings, wing spars, and elevator. In a subsequent conversation the mechanic told the IIC he found the left brake had been over-serviced with fluid, and the right brake linkage was improperly adjusted, leaving the left brake tight, and the right brake loose. In a written statement to the NTSB dated June 6, the pilot wrote that he was taxiing when the left brake locked up.