What happened
The flight was observed climbing to the north while towing a banner. At approximately 300 feet above the ground, the Piper J-3 turned toward the west. During this maneuver, the aircraft appeared to nearly stop in mid-air. The left wing dropped, causing the aircraft to enter a left spin. As the aircraft continued to spin, the engine noise ceased, and the flight ended upon ground impact. There were no fatalities reported.
The investigation
An examination of the aircraft's structure, engine, and flight control systems was conducted. Investigators found no evidence of mechanical malfunction or pre-crash failure. However, following the accident, the elevator trim was discovered to be positioned 1 degree from the full nose-up position. Company personnel noted that while a slight nose-up trim is utilized for banner pickups, the level of trim found after the crash was excessive.