Incident Description
A glider conducting a training landing with a dual student and instructor experienced a runway excursion, striking a taxiway identification sign. The incident occurred when the glider was about to land at the north end of the grass glider landing area.
Sequence of Events
The instructor decided it would be better to land further down the runway. Without informing the student, the instructor partially retracted the spoilers. This action was intended to make the glider float farther before touching down. With the spoilers partially retracted, the wind momentarily shifted to a tailwind. As a result, the glider drifted long and touched down on wet grass. The aircraft continued beyond the intended landing area, slid across a taxiway, and collided with a taxiway identification sign.
Outcome
The glider departed the intended landing area and came to rest after impacting the sign. The source does not specify injuries, damage, or further details about the aircraft or occupants.