A nation's defence doctrine is defined by its vulnerabilities. In Australia's case our geographic vulnerability is the Air-Sea gap. This is the North-West shelf, the Timor Sea and the Coral Sea. In addition to protecting the approaches to Australia by projecting across this gap, there also natural assets such as oil, gas and fishing in these areas. With the retirement of the F111, Australia will be losing a large part of its projection across that area without anything to replace it.
General Dynamics F111 
Photo source: Australian Government Department of Defence Image Gallery - Archive - 000-162-778_075 The F111 got off to a rocky start in Australia, being dominated by politics rather than technology in its early life with the RAAF. The F111 was ordered sight-unseen to replace to replace the Canberra bomber in Australia's inventory. Australian air-power separated its strike forces between fighter and bomber. The F111 was to take over from the bomber as Australia's long-range strike platform.
The advantages of the F111 were its high top speed, its huge range - nearly 6,000 kms, and its avionic autonomy. The F111 could range up the Indonesian archipelago with near impunity. As a deterrent it was unrivalled in the region.
Airframes wear out over time, and the F111 has been in operations since the early 1970s. As the airframes accrue more hours, the maintenance cost to keep them operational starts to increase drastically. The F111 is finding itself in this situation.
Unfortunately, there is nothing to replace it when it is retired. The Joint Strike Fighter is still a long way off being deployed to the United States, let alone Australia. Despite the miniaturisation of precision guided technology, the JSF does not have the projection power of the F111.
So what to do about it?
The government could order more JSFs to make up the projection power imbalance, and then support them with more force multipliers such as AEW&Cs; and Air to Air Refuelling assets (AAR). But recently the government passed up on a seventh Wedgetail, despite the systems already having been paid for.
Air to Air Refuelling remains an issue even with AIR5402. Currently Australia uses converted Boeing 707 aircraft that have been in the Australian fleet since the late 1970s after serving with QANTAS. In the 1990s these began to be converted to tankers. AIR5402 will replace the 707s with five EADS-CASA A330-200s. These are medium sized tankers. Five is also a pitifully small number to support the number of JSFs being purchased.
Even with the purchase of the tankers in 2009, there will be not only a drop in projection, but a drop in the ability to sustain projection across the Air-Sea gap.
The government has also had made some unusual defence purchases recently, such as the second hand Abrams tanks and the mammoth LHD ships. While there has been debate in defence policy between expeditionists and regionalists, all the Defence White Papers have stated that the defence of Australia and the securing of its air and sea gaps come first. It appears that this stated policy is no longer as focused as it should be.
