Incident Summary
The pilot reported that during the climb following the banner pickup, the aircraft developed an unusual vibration and the aileron controls felt sloppy. In response, the pilot turned the aircraft back toward the airport. He planned to drop the banner if the issues cleared up, but the problems persisted, so he kept the banner attached.
Approach and Landing
As the aircraft approached the runway, the pilot applied full engine power in an effort to float until the banner settled. The float did not occur, and the aircraft touched down hard.
Postcrash Examination
After the accident, an FAA inspector and wreckage recovery personnel examined the aircraft. The examination covered the flight controls, structure, and engine. No evidence of any precrash failure or malfunction was found.