What happened
On April 07, 2019, a student pilot was conducting training flights at Warsaw Babice (EPBC) using a winch launch method. After completing several successful flights in a Puchacz glider, the pilot transitioned to a SZD-51-1 Junior. During the climb phase of the second flight in the Junior, the trim spring fractured. Although the flight continued normally until the release altitude of approximately 300 meters was reached, the pilot failed to pull the release handle to disconnect from the winch cable.
As the pilot began executing a turn, the winch operator and the flight manager both issued repeated radio commands instructing the pilot to release the cable. Because the pilot did not respond to these instructions, the winch operator followed standard procedure and manually severed the cable. The pilot subsequently released the cable, completed a circuit, and landed the aircraft safely. The severed portion of the cable and parachute fell within the airfield area without causing injury to anyone on the ground.
The investigation
The investigation established that the student pilot had recently engaged in a discussion with another student regarding different types of glider release mechanisms, specifically those with automatic release functions. The investigation found that the pilot incorrectly assumed the SZD-5eler-1 Junior was equipped with an automatic release mechanism. Furthermore, the pilot misinterpreted the vibration or sensation caused by the fractured trim spring as the activation of an automatic release.
Findings
- The primary cause of the incident was the failure of the student pilot to release the winch cable.
- The pilot began performing a standard circuit pattern without verifying that the cable had been disconnected.
- The pilot operated under the false assumption that the aircraft featured an automatic release function.
- The fracture of the trim spring served as a contributing factor, as the pilot misidentified the mechanical failure as a successful automatic release of the cable.