ASD can trace its origins back to two Second World War organisations: Central Bureau and Fleet Radio Unit Melbourne (FRUMEL). Australian Military Forces, Australian Imperial Forces and Royal Australian Air Force personnel were brought together to form Central Bureau to support General MacArthur’s South-West Pacific Area Command. Royal Australian Navy personnel formed FRUMEL to support the United States Navy by intercepting and decoding Japanese radio signals. Both Central Bureau and FRUMEL formed in 1942.
Central Bureau consisted of intelligence personnel from Australia, the United States, the United Kingdom, Canada and New Zealand. Attached to General MacArthur’s headquarters, the organisation formed in Melbourne before moving to a large house called ‘Nyrambla’ in Brisbane in late 1942. The Australian personnel were responsible for a range of tasks, including traffic analysis, which required them to study the ebb and flow of messages between Japanese units, and to keep track of who was sending messages and who was receiving them. The American personnel were responsible for a practice known as cryptanalysis, which required them to break Japanese codes and ciphers in order to read encrypted messages.
Central Bureau was also responsible for communications security. In support of this effort, members of the Australian Women’s Army Service (AWAS) set up in the garage at Nyrambla. Known as the ‘Garage Girls’, they sent and received encrypted communications using British TypeX encryption machines, communicating with units deployed across the Pacific and with Australian, United States (US) and United Kingdom (UK) signals intelligence counterparts around the country and the world.
Located at the Monterey Apartments in Melbourne, FRUMEL consisted of personnel from the Royal Australian Navy and US Navy. The men and women of FRUMEL worked in teams to collect, analyse, decrypt, translate and report on Imperial Japanese Navy communications in the South-West Pacific. Reporting to the US 7th Fleet, the intelligence collected by FRUMEL was instrumental to a number of naval successes in the Pacific theatre.
Central Bureau and FRUMEL were disbanded after Japan surrendered in August 1945. On 23 July 1946, the Australian Government approved-in-principle the establishment of a new peacetime signals intelligence organisation. In April 1947 the Defence Signals Bureau was formed, with former members of Central Bureau and FRUMEL joining its founding ranks.
