The two gliders were taking part in a cross country skills development exercise with a team leader in a third glider. The team leader was ahead of the other two and waiting for them. VH-GGT was established in a thermal when the pilot sighted VH-GEZ tracking towards him. The pilot of VH-GGT levelled the wings to allow VH-GEZ to join the thermal. He then banked and resumed circling in the same direction. He heard a bang and felt the glider lurch and realised that the two gliders had collided. Both pilots carried out handling checks and the team leader carried out a visual check of the damage. The pilots then elected to fly 30 kilometres back to Tocumwal. The pilot of VH-GGT stated that his glider felt "funny" just before landing, and as he stepped out of the cockpit after landing the entire rear fuselage folded upwards, held by a double thickness of fibre glass only a few centimetres across. VH-GEZ was found to have considerable compression failures on the underside of the wing.