Both pilots were at Horsham to compete in the annual "Horsham Week" gliding competitions. On the day of this accident no task had been set but both pilots had taken the opportunity to make pleasure/familiarisation flights of the area. At the time of the accident the two aircraft were at approximately 5000 feet above sea level. VH-HDY was flying towards Horsham on a constant heading of approximately 330 degrees. The aircraft was in a descent and the pilot estimated he was about 1000 feet below the cloud base. Cloud cover was reported as six eights of cumulus type cloud. VH-KYO was flying in the opposite direction to VH-HDY, also on a constant heading at the same altitude. The pilot of VH-HDY reported that he had just completed a scan of his instruments when he looked up to see the other glider head on. He pushed the control column forward to try and avoid a collision but this was not successful. The pilot of VH-KYO reported that he had also looked up from concentration on another task, to sight the other aircraft head on at the very last moment. He had no time to take any avoiding action. The right wing of VH-HDY hit the nose/cockpit area of VH-KYO, smashing the canopy, dislodging the instrument panel and damaging the nose. VH-HDY lost two metres of its right wing and became uncontrollable. The pilot abandoned the aircraft and parachuted to the ground. The pilot of VH-KYO received injuries to his right foot and face in the collision but was able to maintain control of the aircraft and fly it back to Horsham where he made a safe landing in a paddock beside the aerodrome. At the time of the accident both aircraft were operating in an environment where the pilots were responsible for maintaining separation from other aircraft on the basis of see and be seen. In this accident both aircraft were approaching head on, both were gliders with thin wings and narrow fuselages, both were essentially white in colour when viewed from head on and both were against a background of whitish coloured cloud. Such circumstances would have made it very difficult for each pilot to sight the other's aircraft.