What happened
On August 1, 1962, at approximately 16:50, a student pilot was performing spiral maneuvers in a Piper Cub J3C, registration HB-OFH, near the Speck-Fehraltorf airfield. The flight was part of a training session organized by the Flugsportgruppe Zürcher Oberland. After completing several left-hand turns, the pilot began a series of right-hand spirals at an altitude of approximately 850 meters.
During the third right-hand turn, the pilot perceived a loss of airspeed and attempted to correct the situation by applying more pressure to the controls. This corrective action caused the aircraft to enter a steep dive. The pilot was unable to recover control, and the aircraft descended into a residential area. The Piper Cub J3C struck a garden fence, clipped a building's entrance canopy, and ultimately came to rest against a house wall. The impact resulted in one person suffering severe facial injuries, the total destruction of the aircraft, and minor damage to the property.
The investigation
SUST examined the flight training records, the pilot's qualifications, and the aircraft's maintenance history. The investigation established that the student pilot had approximately 21 hours of total flight time and had previously practiced spirals both in a dual-control configuration and once in solo flight. The aircraft, a Piper Cub J3C, was found to be in good mechanical condition with no technical defects contributing to the accident. The weather at the time of the occurrence was clear with excellent visibility.
Findings
- The primary cause of the accident was the pilot's loss of control during a maneuver.
- The pilot's attempt to correct a perceived loss of speed led to an over-correction, which transitioned the aircraft into an unrecoverable dive.
- While the pilot's initial altitude and entry into the maneuver were appropriate, the student lacked specific training in recovering from unintended stalls or spins.
- The investigation noted that the flight instructor's supervision and the overall training precision lacked the necessary thoroughness to ensure maximum safety during such advanced maneuvers.