What happened
The accident involved a tailwheel (conventional gear) aircraft that had been fitted with a Robertson Short Takeoff and Landing (STOL) modification. According to the pilot's report, this specific modification reduced the stall speed of the airplane to between 28 and 30 knots. The incident occurred while the aircraft was operating within the traffic pattern at an airport equipped with an air traffic control tower.
During the approach, the tower instructed the pilot to maintain a higher airspeed and execute a long landing to create additional spacing for another aircraft that was following in the sequence. The pilot complied with these instructions and proceeded to land on runway 22. At the time of the landing, there was a headwind component of 10 knots, with gusts reaching up to 15 knots.
Upon initial touchdown, the aircraft bounced back into the air. Recognizing the situation, the pilot applied power to regain control and completed the landing. Immediately after the wheels contacted the ground again, the pilot applied the brakes. Shortly thereafter, the nose of the aircraft pitched forward violently, causing the airplane to nosed over.
The investigation
Post-acc examination revealed no evidence of mechanical failure that could have contributed to the mishap. Specifically, there were no reported malfunctions involving the flight control systems or the brake system. The pilot stated that the ground speed at the moment the accident occurred was not exceeding 15 miles per hour.
Findings
The primary factors leading to this incident included the aerodynamic characteristics of the tailwheel configuration combined with a bounced landing. The application of brakes during or immediately after a bounce in a conventional gear aircraft can rapidly shift the center of gravity forward, potentially causing the nose to drop and strike the ground. The Robertson STOL modification, while lowering stall speed, may have influenced the pitch stability and control responsiveness during the critical low-speed phase of flight.