The pilot was competing in a cross country gliding competition when it became apparent to him that an outlanding would be necessary. He then positioned the glider to carry out a circuit for a landing in a paddock. After turning the aircraft onto final approach and deploying full airbrake, the pilot noticed that the indicated airspeed had greatly reduced. He then attempted to close the airbrake but the nose of the aircraft dropped and struck the ground. The aircraft bounced on impact and came to rest 17 metres beyond the initial point of impact.