On August 13, 1997, at 0645 hours mountain standard time, an Aerostar S-55A, N3607B, collided with a power line during the initial ascent from Marana, Arizona. The balloon's propane line ruptured, an in-flight fire ensued, and the balloon subsequently crashed. The balloon was destroyed by the in-flight fire. The private pilot and his passenger sustained serious injuries. The aircraft was operated as a personal flight under 14 CFR Part 91 when the accident occurred. The flight originated in Marana at 0644. Visual meteorological conditions prevailed at the time of the accident. The pilot stated that this was his second flight of the day. He took off from the same location at 0605 with one passenger prior to this flight. He stated that the second flight segment had a lighter weight passenger onboard than was the case with the first flight. He stated that the "wind blew him into the power line," at an altitude of approximately 50 to 60 feet above ground level. The pilot originally told the Federal Aviation Administration that the wind "picked up to 18 knots from 110 to 120 degrees." The pilot stated in his written report that his "first mistake was deciding to land upwind of the power lines." He said that immediately after takeoff, the balloon basket contacted, then cleared, a barbed wire fence. He stated that he should have aborted the flight upon contact with the fence, but that he elected to continue. The balloon continued to climb slowly, even with the double burners on full. The pilot stated that he "felt at this point that the only choice was to climb over the power lines, but missed clearing them by three feet." According to the pilot, the power line broke in the collision sequence and arced the fuel tank. The arcing burned a hole in the fuel tank, which then ignited a jet of propane fuel, which subsequently caught the wicker basket on fire.