AO-1990-049

[No official abstract. The following is derived from the report.] The glider took off on tow with the airbrakes open. At 20 feet after take-off the glider pilot saw the tug aircraft signalling with its rudder and interpreted this as a signal to cast off. He did so, and turned back towards the aerodrome. The tailplane was damaged when the aircraft clipped the fence as it crossed the boundary. When the aircraft came to a halt the pilot realised the brakes were still open. A safety recommendation was made to the President of the New Zealand Gliding Association.