June 8, 2012: It's recently been revealed that three years ago Australia began planning for a possible war with China. Until now, all that was public was a 2009, military expansion program ("Force 2030") that called for new submarines and an expansion of the sub force from six to twelve boats. There was a secret section of the plan that discussed the need for the larger submarine force to join with the U.S. fleet to shut down Chinese exports (of manufactured goods) and imports (of food, industrial supplies, and raw materials). This part of the plan was kept secret so as not to offend the Chinese. While most Australian China experts do not believe China would ever start a war of conquest, China is becoming quite the regional bully. China could miscalculate while doing this, leading to war. Australia wants to be prepared.
The Australian Navy still plans to make submarines the key component of the fleet. Over the next two decades Australia will still double the number of subs in service, from six to twelve. This will mean that more than half (12 out of 23) of their major warships will be subs. The new class of 12 subs will replace the Collins boats in the 2020s. The new boats will be larger (about 4,000 tons) and cost about $2 billion each (more than the U.S. Virginia class nuclear powered attack subs). The new subs would carry cruise missiles in addition to torpedoes and mines, be quieter, and be equipped to do reconnaissance as well as combat missions.
The current Collins class boats were built in Australia and delivered between 1996 and 2003. They are based on a Swedish design (the Type 471). At 3,000 tons displacement, the Collins are half the size of the American Los Angeles class nuclear attack subs but are nearly twice the size of European non-nuclear subs. Australia needed larger boats because of the sheer size of the oceans in the area.
The new class of subs is going to build on the Collins design and will probably have an air-independent propulsion (AIP) system. This enables the sub to stay underwater for over a week at a time. The decision to expand the size of the sub fleet will take time because the "Collins Replacement" boats will not start entering service until 2030, several years after when the oldest Collins class sub is ready for retirement. The first Collins class boat entered service in 1996, and was built to last for 30 years.
Australia is also acquiring new warplanes (F-35s) and amphibious ships as part of its "being ready for an aggressive China" program.