What happened
The pilot was operating a glider in a right traffic pattern for Runway 16. During the downwind leg, at the midfield point, the aircraft was at an altitude of 1,000 feet when the pilot extended the spoilers. The base leg of the pattern was completed at approximately 700 feet above the ground.
Upon turning onto final approach, the pilot attempted to initiate a slip by applying left rudder and keeping the right wing down. After determining that the initial slip was ineffective, the pilot leveled the wings momentarily before re-entering the slip.
The aircraft touched down approximately 90% down the runway and continued past the end of the paved surface. The glider then became airborne a second time, turned to the right, and made a subsequent touchdown on a road. During this phase, the glider struck several road signs with both wings before rotating 180 degrees and coming to a stop. The pilot was not injured.