Glider Collides with Parked Aircraft at Bad Ragaz (HB-3084)

Accident

On 30 March 1992 at 1515 local time, a SZD-55-1 glider, registration HB-3084, was conducting its seventh conversion flight on the type at Bad Ragaz airfield. The glider was towed by an aircraft for takeoff on runway 12 with variable wind of 5–10 knots. Shortly after the tow aircraft began moving, the right wing of the glider contacted the ground to the right of the paved runway. Despite the pilot applying full opposite control, the wing was braked by the low grass and the glider left the paved runway after about 30 meters. Unable to correct the attitude, the pilot released the tow rope attached to the nose hook after approximately 50 meters. The tow aircraft pilot aborted the takeoff, and the glider continued rolling unbraked toward a hangar. After a total roll distance of about 100 meters, the glider collided heavily with a parked Mooney M20J (HB-DFB). The glider sustained minor damage, and the parked aircraft was substantially damaged. The pilot suffered minor injuries.

Findings

• The pilot held a valid glider pilot license.
• No evidence of pre-existing medical issues was found.
• The glider had a provisional airworthiness certificate.
• The right aileron control lever had been incorrectly installed by the manufacturer. Both ailerons had an excessive positive setting. This misadjustment was discovered only after the glider was taken to the factory for repair. No other pre-existing defects were found that could have caused the accident.
• The tow rope was attached to the nose hook during takeoff.
• Mass and center of gravity were within limits.
• Weather at the time: variable wind 5–10 knots, with occasional foehn gusts up to 20 knots; visibility more than 30 km; cloud cover 4–8/8 with base around 2000 m; temperature 13°C, dew point 0°C; QNH 995 hPa.
• The pilot had 2 hours 46 minutes and 6 landings on the accident glider type.

Causes

The accident was attributed to:

• Wing contact with the ground during takeoff, causing the aircraft to leave the runway.
• The tow rope not being released in a timely manner.
• Reduced aileron effectiveness due to an incorrectly installed lever in the factory.
• Failure to apply the wheel brake.

These factors led to the glider rolling unbraked into a parked aircraft.