What happened
On May 16, 2013, a private owner arrived at the Częstochowa Aeroclub (EPRU) to conduct a training flight in a SZD-42 Jantar 2 glider, registration SP-2961. Due to the unavailability of the aeroclub's standard glider tug, the pilot arranged for a tow using a Cessna 206 equipped with a towing hook. After coordinating takeoff procedures with the aircraft pilot, the glider was positioned into the wind for a takeoff run on heading 120°-130°.
During the takeoff roll, the glider lost directional control and veered to the left. In an attempt to facilitate a quicker liftoff and regain alignment, the pilot adjusted the flap setting from -2 to +1. However, the propeller slipstream, acting primarily on the right wing, combined with reduced lateral control, caused the glider to bank heavily to the left. As the aircraft lifted off, the left wing struck the ground, generating a massive yawing moment that caused a violent leftward rotation and a sudden descent. The impact resulted in the structural failure of the tail boom. The glider subsequently rolled onto its right wing and struck the ground in an inverted position, where it was dragged several dozen meters by the towing aircraft.
The investigation
The PKBWL investigation focused on the sequence of events during the takeoff roll and the mechanical and aerodynamic factors contributing to the loss of control. The investigators examined the aircraft's configuration, specifically the flap adjustment, and the aerodynamic effects of the propeller slipstream from the Cessna 206. The investigation also reviewed the lack of visual aids for the towing pilot and the absence of ground-based flight monitoring during the maneuver.
Findings
- The primary cause of the accident was a pilot error involving improper flight technique, specifically the failure to release the towline immediately when the glider lost directional control during the takeoff roll.
- The pilot's decision to change the flap setting to +1 contributed to the instability, as the propeller slipstream from the tug induced a heavy leftward bank.
- The absence of a flight controller on the ground meant there was no external observer to issue a command to abort the takeoff or release the cable.
- The towing aircraft was not equipped with a rearview mirror, which prevented the towing pilot from identifying the glider's deviation from the centerline.
- A sudden wind gust or thermal turbulence may have contributed to the initial loss of directional stability.
Following the accident, the pilot sustained facial injuries and general contusions but did not suffer life-threatening trauma.