The Royal Australian Air Force ordered its first 18 PBY-5s in 1940, intending to use them for naval patrols. However, following the declaration of war on the Japanese Empire by the British Empire and its Commonwealth, the Catalinas were pressed into a number of different roles. The initial Japanese offensives in Southeast Asia were immensely successful, with the Fall of Singapore in February 1942 leading to the abandonment of the Singapore strategy and the adoption of a policy of general withdraw being enacted by the Australian armed forces. This turn of events isolated tens of thousands of Allied soldiers and civilians from Allied controlled territories. In response, RAAF Catalinas (among other aircraft) formed a rapid evacuation service from Java for hundreds of evacuees who were ferried to the port of Broome, Western Australia. During the last weeks of February 1942 more than 7000 people were successfully transported to Broome. Concerned with the evacuations and seeking to limit Allied bomber activity, the Japanese attacked Broome on 3 March 1942, destroying eight Catalinas along with 14 other aircraft. The attack led to a period referred to as the Western Australian emergency of March 1942, during which Catalinas were deployed to scout for a possible Japanese invasion force.