http://www.theadvertiser.news.com.au...55E421,00.html
The RAAF's additional airborne early warning planes will mean a
return to the original project plan for six aircraft.

http://www.airforce-technology.com/projects/737aewc/
The program provides for four AEW&C systems with options for up to
three additional systems.
....
The radar has a system track capability of 3,000 targets and can track
air and sea targets simultaneously.

Combined with JSF and airborne refueling this should keep Australia's
coastline and fishing areas safe from invasion.

-HJC