Expansion of R430 Tidbinbilla

Higher power radio transmitters are planned to be installed, requiring an expansion of R430.

The issue

• Australia’s space treaty with the United States of America (USA) supports the National Aeronautics and Space Administration's (NASA’s) deep space exploration via the Deep Space Communication Complex at Tidbinbilla
• crewed spaceflight and increased demands from the space industry require an increase in communication transmitter power
• High Intensity Radio Frequency (HIRF) exposure standards limit exposure to protect aviation safety systems and to prevent human harm (thermal stress)
• Additional restricted airspace layers at Tidbinbilla (R430) are required in Class C airspace above 8,000 feet (ft) above mean sea level (AMSL) to ensure compliance with HIRF exposure standards that impact arrival, departure and transit routes for Canberra.
• No changes required to the dimensions of R430C 4,500ft to 8,000ft AMSL.
• No changes required to the existing low level Class G airspace R430A, B SFC to 4,500ft AMSL.

Purpose

The Commonwealth Scientific and Industrial Research Organisation (CSIRO) currently operates X-Band 20 kilo watt (kW) transmitters on 34 metre diameter antennas at its Tidbinbilla site. There is a need to increase the power to 80kW. This will increase HIRF in the vicinity of Tidbinbilla. There is a potential aviation safety impact requiring mitigation through change to restricted airspace.

Proposal

To support future space missions, there is a proposal to build an X-band 80kW transmitter on a 34m diameter antenna at the Canberra Deep Space Communications Complex (CDSCC). Under this proposal, transmitter testing is planned for October 2028 to become operational in October 2029. The higher intensity transmissions from the Tidbinbilla site have the potential to exceed aircraft certification limits for aircraft flying within 8.7 nautical miles (n mile) of CDSCC up to FL215. Detailed analysis has shown that the current restricted airspace R430 up to a 5.0 n mile radius and up to 10,000ft AMSL would need to be expanded up to an 8.7 n mile radius and up to FL215.
There are a number of air routes and Canberra Flight Procedures that would be affected by such a change. The 6-year lead time to build, test and operate an 80kW transmitter on a 34m diameter antenna requires forward planning. With feedback from this Aviation State Engagement Forum (AvSEF) submission, discussions with CASA and with Airservices, CSIRO intends to submit an Airspace Change Proposal ahead of changes to air routes and Canberra Flight Procedures. For equitable use of airspace, changes to air routes and Canberra Flight Procedures can only be made once the 80kW transmitter begins testing and radiates to sky, planned from October 2028. As a result of the expanded airspace, new flight paths will be developed by Airservices in due course and following due processes.

Please see the attachment below for more detailed information on the proposal.

Relevant documentation