In October 1990 Australian Airlines become the outright owner of Sunstate Airlines and Sunstate Airlines (Mildura). The Mildura operation was subsequently rebranded as Southern Australia Airlines, commencing operations under that name on 1 January 1992. The following month it took delivery of its first pressurised aircraft, a de Havilland Canada DHC-8-100 Dash 8. A second Dash 8 was delivered in March 1992 and the Short 360 was transferred to Sunstate Airlines in July. Southern Australia used the Dash 8s to expand its services, taking over Eastern Australia Airlines routes across Bass Strait from Melbourne to Launceston and Devonport in Tasmania.