The need for the RAN to have replenishment capabilities has been recognised for over half a century, when plans began for the acquisition of such a vessel that would eventually become HMAS Success, although it wouldn't be until 1986 that the support ship would enter service for the Navy.
Until Sirius entered service in 2006, it was for two decades a support flag that Success would carry alone, steaming close to 1 million nautical miles in her 33-year commission, providing vital lift capabilities for the RAN, ADF and allied forces around the world.
The growing complexities of the geo-strategic, economic and political competition sweeping throughout the Indo-Pacific has prompted the development of a number of competing centres of strategic gravity – each with individual tactical and strategic factors directly influencing the force structure and force posture to enable the Navy to adequately meet the objectives identified by government.
To the nation’s immediate north, the combination of narrow, relatively shallow strategic waterways and vast tracts of open ocean in the South China Sea requires a drastically different approach to developing force structure and capability development when compared with the forces required to operate in the vast, open ocean of the Indian Ocean or the coral atoll, temperate waters of the Pacific.
It's therefore obviously a longstanding discussion over the need for at least three, or more, replenishment vessels, but never has that conversation been more relevant than today and looking forward to the future.
Rule of three
The simplest starting point is the general rule of thumb with military deployment, in that one force should be available for operations, the second to be on standby, and the third recovering from operations.
While it's not a rule the RAN have subscribed to for the Canberra Class landing helicopter dock (LHD) fleet (and also not for HMA Ships Success and Sirius), the Hobart Class destroyers are coming as a trio, the Attack Class submarines are planned for 12 acquisitions (replacing the six Collins Class subs), and nine Hunter Class frigates slated to replace the eight Anzac Class frigates, which were originally slated for 12 vessels.
The British and French even apply a rule of fourths to their submarine-launched ballistic missile forces, where one submarine is deployed on patrol, one preparing for patrol, one returning from patrol and a fourth in maintenance.
While the above isn't overly applicable to AOR vessels, NUSHIPS Stalwart and Supply will have their hands full when they enter service in 2020. With the RAN's planned acquisitions, and Australia's increasingly growing role in the Indo-Pacific (more on that shortly), it's fair to question whether two AOR vessels is enough to carry the replenishment load for the RAN.
A busier Indo-Pacific and easing the operational burden
While the RAN and the ADF have managed to get away with using just two supply vessels for the past three decades, it's no secret that the oceans in our region are going to reach unprecedented levels of activity over the next 20 years.
In the Navy's own words, the vessels, in addition to replenishment, "can be used to combat against environmental pollution at sea, provide logistics support for the armed forces, and to support humanitarian and disaster relief (HADR) operations following a natural disaster".
Anticipating the rapidly evolving strategic, economic, political and diplomatic situation throughout the region, particularly in the Pacific following increasing investment and interest by the Chinese, the 2016 Defence White Paper (DWP) and the current Liberal government under Scott Morrison have identified the need for a greater Australian capacity to engage with the region and show a committed Australian presence.
The addition of a third AOR platform also serves to enhance both the tactical and strategic flexibility and capacity of the ADF and Navy, in particular, to respond to any number of contingencies as they develop and further support the Australian government's ambitious 'Pacific Step-up' program – the acquisition of an additional AOR platform also serves to ease crew and platform burnout, and frees up the existing platforms to undergo deeper, more regular cycles of maintenance and training prior to operational deployment.
In a region that is anticipated to see an explosion of activity over the next 15 years, is it reasonable or fair to expect just two AOR vessels to carry the replenishment load?
Defence and the government clearly recognise the projected contested nature of the Indo-Pacific region (see 12 Attack Class submarines and nine Hunter Class frigates), are they overlooking the need for these replenishment vessels to both support the ADF and allied forces in the area?
Need for discussion
There are certainly a few counter points, not least of all in regard to the man-power a third (or preferably more) AOR vessel would require, as well as the cost. Together, HMAS Choules, the Canberra Class amphibious ships and the Supply Class replenishment vessels will enable the ADF to conduct a greater number of challenging maritime operations at the same time, and to sustain those operations for longer periods than it can today.
Enhancing Australia’s capacity to act as an independent power, incorporating great power-style strategic economic, diplomatic and military capability serves as a powerful symbol of Australia’s sovereignty and evolving responsibilities in supporting and enhancing the security and prosperity of Indo-Pacific Asia. Shifting the public discussion away from the default Australian position of "it is all a little too difficult, so let’s not bother" will provide unprecedented economic, diplomatic, political and strategic opportunities for the nation.