Accident Overview
On September 3, 2023, at about 1420 Pacific daylight time, a Piper PA-18-135, registration N7199K, was substantially damaged in an accident near Compton, California. The pilot, who was the sole occupant, sustained minor injuries. The airplane was operated as a banner tow flight under Title 14 Code of Federal Regulations Part 91.
Sequence of Events
According to the pilot, shortly after takeoff during the banner tow operation, the back of the pilot’s seat broke, causing him to slide aft into a horizontal position. This abrupt rearward movement resulted in the pilot pulling back on the control yoke, which led the airplane to pitch up to a nose-high attitude. Due to the high pitch attitude, the pilot slid further back in the seat. Unable to push the flight control stick forward, he let go of the flight controls and used a crossbeam to pull himself forward.
When the airplane was about 200 ft above ground level and at the onset of an aerodynamic stall, the pilot managed to push the flight control stick forward and recover the airplane. However, as he recovered from the imminent stall, the engine began to “cough” and sustained a partial loss of power. Unable to maintain altitude, the pilot elected to make a forced landing to a nearby baseball field. During the descent, the airplane impacted a fence along a concrete wash and came to rest upright.
The pilot believes that when he fell back or when he was pulling himself forward, his foot or knee may have moved the fuel selector lever out of the “both/on” position.
Postaccident Findings
Postaccident examination of the airplane revealed that both wings were substantially damaged. The pilot’s seat back frame was fracture separated on the left and right side near the back rest and seat junction. Examination of the engine revealed no preaccident mechanical malfunctions or failures that would have precluded normal operation.
The pilot’s seat was sent to the National Transportation Safety Board Materials Laboratory in Washington, DC, for examination. Examination of the fracture surface revealed characteristics consistent with an overstress fracture. A review of the airplane’s maintenance records could not determine the age of the pilot’s seat or if recent maintenance had been performed on it.