Decisions made in the next few months on buying additional Joint Strike Fighter aircraft could give the RAAF a huge advantage over any adversary.
Air Force chief Air Marshal Geoff Brown says that given the long lead times on complex weapons systems like fighter aircraft, the force Australia will field in 2025 and beyond is "pretty much" decided by decisions to be made in the next few months.
He told a conference on air combat operations in 2025 and beyond that the pace of technological change meant Australia could not become complacent.
Australia is planning a fleet of up to 100 advanced JSF aircraft but has committed to buying just two, which will be delivered in the US for training in 2014 and 2015.
In the 2012 budget, the former Labor government opted to defer purchase of the next 12 for two years to allow time for technical problems to be resolved.
Air Marshal Brown said air power was a critical element of Australia's national security and fifth-generation aircraft such as JSF offered a quantum leap in capabilities.
"The mission they undertake may not be new but the capability that fifth-generation fighters bring will vastly change the character and effectiveness of how the missions are undertaken," he said.
"As we look beyond 2025 I can only wonder how long until a fifth-generation fighter is not sufficient and we start asking the question of where's the sixth-generation fighter."
Fifth-generation aircraft are characterised by stealth technology, which makes them difficult to detect on radar, superior sensors to allow targets to be detected without their knowledge and advanced networking to receive and disseminate data to and from multiple sources.
By comparison, first-generation jet fighters used in the Korean War were equipped with guns and bombs but no radar or guided weapons.
