On June 26, 1997, approximately 1945 mountain daylight time, a Cessna 305A, N5225G, registered to Banner Advertising, Inc., was destroyed when it impacted terrain while maneuvering at Aurora, Colorado. The commercial rated pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the business flight being conducted under Title 14 CFR Part 91. The flight was originating. According to airport personnel, the pilot took off from the Aurora Airpark (01V) on runway 14 into a 20 to 25 mph headwind. He then turned downwind, snagged a banner he intended to tow, applied full power, and leveled the airplane. According to the pilot's report, "the aircraft began to vibrate wildly and lose power. The vibration and lack of power continued until the airplane impacted the ground at a 30 degree angle." According to witnesses, however, the airplane stalled and impacted a field adjacent to the airpark. The pilot later told his insurance adjuster that the vibration was "a classic initiation of a stall." A Federal Aviation Administration inspector noted that the airplane was being used in commercial operations, but had not received regular 100-hour inspections. The wing spar was broken, the firewall was buckled, and the ailerons and right main landing gear were twisted and bent.