Accident Narrative
During a banner towing operation, the pilot was on approach to drop the banner. Upon pulling the tow release, the banner did not detach from the airplane. The banner subsequently struck the ground, broke away from the aircraft, and the airplane nosed over. The pilot reported no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.
Postaccident Findings
A postaccident examination of the airplane revealed substantial damage to the empennage. The release mechanism, which incorporates three hooks (typically only the No. 1 hook is used), was inspected but no anomalies were found that would have prevented the banner from being released. The pilot believed that the ground crew mistakenly set up hook No. 3 to pick up and tow the banner instead of the intended No. 1 hook. Consequently, when the pilot attempted to release the banner from hook No. 1, there was nothing to release.