Defence Signals Directorate: Timor Leste, 1999

Defence Signals Directorate: Timor Leste, 1999


Interception of Indonesian military communications is a primary task of the Defence Signals Directorate, primarily through the facilities at Shoal Bay. 

Commentary and analysis

Death in Balibo, Lies in Canberra, Desmond Ball and Hamish McDonald, Allen and Unwin, Sydney, 2000.

Brian Peters Findings, Coronial Findings and Recommendations, Coroner’s Court New South Wales, especially Chapter 9 “SIGINT”, pp 74-93.

Desmond Ball, “Silent Witness: Australian intelligence and East Timor”, Masters of Terror: Indonesia’s Military and Violence in East Timor in 1999, [co-edited with Desmond Ball and Gerry Van Klinken], (New York: Rowman and Littlefield, second edition, 2006).

DSD’s largest intercept station is located at Shoal Bay, near Darwin, where some 120-150 people worked through 1999, listening with earphones to Indonesian radio traffic, recording encrypted signals, and monitoring satellite telephone conversations.

The Shoal Bay station has two different signals interception systems. One is a large circular antenna array, code-named Pusher, which is used for interception, monitoring, direction-finding (DF) and analysis of radio signals in the high frequency (HF) band. This system intercepted radio communications among ABRI and militia units in East Timor, between ABRI officers in the field and the East Timor Command in Dili, between Dili and the HQ of the Udayana Regional Military Command or KODAM (Komando-Daerah Militer) IX in Denpasar in Bali, and between Dili and ABRI HQ in Jakarta.

The second system, code-named Larkswood, is concerned with the interception of Indonesian satellite communications, and especially those involving Indonesia’s own Palapa communications satellite system. It became operational in 1979, and during its first decade had only two dish antennas, for monitoring the two Palapa satellites then in service. In the late 1980s, according to the then Minister for Defence, ‘the station [was] modified in response to changing requirements and this included the installation of several dish antennas’. These must have been temporary, because at the time of the massacre at the Santa Cruz cemetery in Dili in November 1991, there were still only two dish antennas. But many more were installed in the late 1990s, making eleven as at September 1999 (including two small dishes on the roof of the main operations building). Most of the new antennas were designed to intercept various sorts of satellite communications involving Indonesia, including mobile satellite telephone (satphone) conversations using INMARSAT and other services. By 1998, it seemed that ABRI officers throughout the archipelago were using satphones more than their Army radios to communicate with Jakarta. Some of the new dishes were installed to provide direct relay of the intercepted material, as well as ‘first echelon’ translations and analyses, to the DSD HQ and the DSD liaison offices in the ONA and DIO buildings at Russell Hill.

In addition, small teams of Navy SIGINT personnel from Shoal Bay served aboard some of the Navy’s frigates and patrol boats, which were able to operate close to East Timor. These teams intercepted VHF/UHF transmissions as well as low-power HF signals, such as walkie-talkie and field radio communications. DSD was also able to use two P-3C Orion aircraft which had been specially configured for SIGINT operations in 1995-98 (under Project Peacemate).

See also

Updated: 14 June 2009