The aircraft joined the circuit for a landing on the duty runway, 06. On short final the pilot was advised that there was a 3 knot tailwind. She continued with the landing and as the tail was lowered to the runway, after touchdown, the aircraft began to accelerate and yaw to the left. Corrective action was taken and the yaw stopped. However, as the pilot applied the hand operated brake, the aircraft again yawed quickly to the left and ground-looped before coming to rest on the right wing tip and nose. During the landing the wind had changed from a light north-easterly to an 18 knot south-westerly.