Airservices Australia will propose using the benefits of ADS-B technology to restrict tower control to 4500 feet at five Class D airports around the country.
Airservices CEO Jason Harfield outlined the plan at the Regional Aviation Association of Australia (RAAA) convention on the Gold Coast last week.
According to Harfield, the full advantages of ADS-B should enable the service provider to transfer responsibility for aircraft over 4500 to an en route controller. Currently, the towers are responsible for separation and control up to 8500 feet.
"The benefits [of ADS-B] for regional aviation will be realised progressively as we see more aircraft in the sky, as we underpin the safe expansion and growth of aviation services across Australia," Harfield told the convention. "This includes more rural and regional areas where we expect to see population growth and tourism expansion.
"As our first step we are proposing that in five locations–Hobart, Albury, Launceston, Alice Springs and Tamworth–we capitalise on the expansion of our surveillance coverage by transferring the control of airspace 4500 feet and above from the air traffic control tower to an enroute surveillance service.
"This move will increase the use of surveillance, improve safety and also contribute to the improved consistency and efficiency across the network."
A spokesperson for Airservices Australia said that as there would be no amendments to airspace design at those airports, Airservices did not need to submit a safety case to the Office of Airspace Regulation.
Airspace design over Class D towers has been a contentious issue for several years. Under the original National Airspace System (NAS) proposals, airspace over the Class D was to have been Class E, which meant VFR flights needed no clearance to transit over the top of the airport.
After trials, the Class E concept was dropped in favour of Class C over Class D to protect inbound RPT flights that operated IFR.