http://www.airservicesaustralia.com/...asp?id=PR15_06
Improved aircraft surveillance across Tasmania - 15/06
Airservices Australia has contracted air navigation technology firm Sensis Corporation to design and install equipment to provide safer and more precise aircraft tracking in Tasmanian skies.
Known as Wide Area Multilateration (WAM), the system will initially be compared to the present secondary radar system in Tasmania in order to obtain regulatory approval from the Civil Aviation Safety Authority (CASA) to use WAM for aircraft separation.
The system, being installed in 2007, will also be used to collect data to support the use of WAM as an alternative technology for precision monitoring of aircraft on final approach to Sydney Airport's parallel runways.
Airservices Chief Executive Officer, Greg Russell said the new system would improve coverage for air traffic controllers compared to that currently achieved with transportable radar and particularly at lower altitudes around Hobart.
'When commissioned in early 2008, the new system will provide complete coverage of mainland Tasmanian airspace and, when coupled with the radar-like aircraft tracking technology ADS-B, will cover a 250 nautical mile radius of Launceston and Hobart,' Mr Russell said.
Multilateration systems determine position through triangulation of data received from aircraft via a number of receiver stations on the basis of time difference.
Mr Russell said multilateration was more accurate than secondary radar.
'The Tasmanian system will provide position data with better than 150 metre accuracy and an update rate for air traffic controllers as fast as once a second,' he said.
Guess it is official then! This will mean a radar-like service down to ground level at Launceston & Hobart with only mode C transponders in the aircraft!