Canberra Airport has enthusiastically welcomed plans by the NSW Premier to build a high-speed train line between Sydney and Canberra and entrench the national's capital as a de facto second airport for Sydney.

Canberra Airport chief Steven Byron expects a Sydney-Canberra bullet train would reduce travel time between the two cities to just one hour, and that building the dedicated high-speed rail link would cost the same as a second airport – but with far less political fallout and much greater opportunity for both cities.

The line has already been proposed as part of a much larger and far more ambitious Aussie bullet train running from Brisbane to Melbourne.

This has already seen a new Southern Concourse Terminal opened in late 2010, which is currently used by Qantas.

Work is now underway on a mirror-image Western Concourse Terminal which will be home to Virgin Australia and regional carriers. 

The airport's runways have also "been lengthened, strengthened and widened to 747 and A380 standard" Canberra Airport chief Steven Byron told Australian Business Traveller last year.

"So we've got a fully kitted-up airport, you can go anywhere off our runway with a fully-laden aircraft that you can go out of Sydney Airport."

Byron considers Canberra as an ideal "overflow airport" as Sydney's congestion continues.

"Sydney will become more crowded and that's when our role as an overflow airport comes into play. We won't formally be a second Sydney airport but we believe there will be parts of the market that will grow for us in response as Sydney's capabilities are challenged."

Byron says he expects services from Canberra "will be flying across the Tasman to both Auckland and Wellington" once the Western Concourse Terminal is completed, after which "we'll see one of the airlines commence services to Singapore." The airport's 2009 'masterplan' also flagged China as a likely 'medium-term' route.

Byron also sees Canberra eventually becoming the natural home of low-cost Asian carriers such as Air Asia X and Jetstar Asia. "I think a decade down the track (Canberra) will be Sydney's low-cost airport for international services" he predicts.

"They'll be squeezed out of  Sydney in due course as the capacity constraint hits, just as the low-cost airlines have been squeezed out of Heathrow and other major 'first airports' in larger cities around the world. We think we'll see the Air Asia X's and Jetstar Asias will be flying out of Canberra."

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