The RAAF contingent was also expanded, growing to include three squadrons—No. 35 Squadron, flying Caribou STOL transports, No. 9 Squadron flying UH-1 Iroquois battlefield helicopters and No. 2 Squadron flying Canberra bombers. Based at Phan Rang Air Base in Ninh Thuận Province the Canberras flew many bombing sorties, and two were lost, while the Caribou transport aircraft supported anti-communist ground forces and the Iroquois helicopters were used in troop-lift, medical evacuation and as gunships from their base at Vũng Tàu in support of 1 ATF. At its peak it included over 750 personnel. During the war RAAF CAC-27 Sabre fighters from No. 79 Squadron were also deployed to Ubon Air Base in Thailand as part of Australia's SEATO commitments. The Sabres took no part in direct hostilities against North Vietnam, and were withdrawn in 1968. The Royal Australian Navy (RAN) also made a significant contribution, which consisted of a destroyer on six-month rotations deployed on the gun-line in a shore bombardment role, the RAN Helicopter Flight Vietnam, and a RAN Clearance Diving Team. The ageing aircraft carrier HMAS "Sydney", after being converted to a troop-ship, was used to convey the bulk of Australian ground forces to South Vietnam. Female members of the Army and RAAF nursing services also served in Vietnam from the outset, and as the force grew the medical capability was also expanded with the 1st Australian Field Hospital established at Vũng Tàu on 1 April 1968.