Friday 17 Aug 2018 | 17:50 | SYDNEY
Friday 17 Aug 2018 | 17:50 | SYDNEY

Why 12 submarines? An imperfect answer

This post is part of the The military numbers game debate thread. To read other posts in this debate, click here.

16 April 2012 14:59

This post is part of the The military numbers game debate thread. To read other posts in this debate, click here.

Derek Woolner is a Visiting Fellow at the Strategic and Defence Studies Centre of the ANU. He is co-author, with Peter Yule, of The Collins Class Submarine Story: Steel, Spies and Spin.

Rodger Shanahan asks for a more rigorous examination of the reasons for adopting 12 as the number of boats to be acquired by the future submarine project. Richard Brabin-Smith's post gives us a clear understanding of how such decisions on national security should be made, with due regard for strategic priorities.

In reality this process is seldom apparent to public gaze and observers can fairly conclude that rigorous analysis is often honoured in the breach. The strategic underpinnings for the future submarine are outlined in the 2009 Defence White Paper (p.63) but with a studied brevity that the Government has since expanded on only slightly.

Project development has necessarily continued, driven by an awareness of when aging equipment must be replaced to preserve Australia's abilities in submarine warfare. A Cabinet submission to initiate elements of the acquisition program was forwarded before the end of 2011. Simultaneously, the major European conventional submarine designers were awarded contracts to study how to enhance their designs to reach the levels of performance demanded by the RAN.

Meanwhile, Government silence on where the project is heading has left public discussion of the future submarines centred on the European commercial options, which the Chief of Navy has dismissed as possessing inadequate performance, and on the nuclear-powered option rejected by Government at the outset.

I suspect the Minister's consideration of the project has been little concerned with strategic priorities but, rather, focused on the issue of equipment maintenance. The development of the future submarine has grown in parallel with publicity about the difficulties of sustaining the Collins fleet. A force that is tasked with being ready to deploy four of its six boats has for long periods had two, one, sometimes no boats on offer.

The Minister can be excused for focusing on RAN fleet maintenance.

The Navy's inability to deploy any of its three amphibious transport ships in February 2011, following Cyclone Yasi, forced a review of maintenance procedures and an interim restructuring of the transport fleet. The Collins' problems prompted the Coles Review, which, in its interim report, identified many deficiencies. Late last month, the Chief of Navy indicated that operations by Armidale class patrol boats, the major component of maritime border security, would be reduced for the rest of 2012; the fleet has been overworked since 2005 and requires urgent maintenance. And last week it was revealed that the aging support ship, HMAS Success, was the next focus of fleet maintenance problems.

I suspect that the Minister has deferred consideration of the future submarine Cabinet submission hoping the final report of the Coles Review, due this month, can provide viable solutions.

Sustaining the operational capability of submarines is a challenging and central issue in submarine warfare. It has generally been frustrating and expensive. The first major maintenance docking of an RAN Oberon class submarine, HMAS Oxley, was performed at the Vickers Cockatoo Island, Sydney, facility of the boat's overseas builder. Finished in 1973, it took longer and cost more than the original purchase. By the 1980s these five-yearly refits were costing four times the acquisition price of the submarines.

The Collins fleet was intended to avoid these costs and improve availability through local production, eight-year refit cycles and other factors. Instead, for a number of reasons outlined in the interim Coles Report, sustainability of the Collins class has been poor.

A more direct strategy to minimise maintenance demands was considered early in the Collins evolution. Important items of equipment, usually mounted outside the pressure hull, could be located inside to reduce exposure to seawater. However, none of the submitted designs met this requirement and the performance sacrificed by limiting space within the pressure hull saw the end of the concept.

Such prioritisation is not unusual. The Astute class (pictured), latest of British submarines, was to have been developed to reduce costs of ownership and improve availability. Instead, the pressures of design and production approval deadlines relegated requirements for sustainment; in service, maintenance and support of the class has become an expensive challenge.

Some 30 years ago, major air forces decided that they could not continue with aircraft that required over 100 personnel maintenance hours for every hour flown. Most combat aircraft from the F-16 onwards have been designed with reduced costs of ownership as a key acquisition objective. This design philosophy has not yet reached the world of submarines but, for a Navy bedeviled with fleet maintenance problems, a future submarine designed from the outset to minimise cost of ownership and increase availability should be very attractive.

Decisions on such acquisition objectives are some way downstream from the other requirements to meet strategic policy. Yet, unavoidably, the engineering complexity of designing a submarine to meet all naval requirements does not allow for a neat streaming of decision-making, especially when the processes of strategic policy seem to be incomplete and the future submarine project is already years behind schedule.

So, how to derive numbers in such an imperfect world? Under the old 'rule of three', six Oberon submarines provided a long-term average of two available for operations. Data on Collins availability has been withheld for some years, so the best that can be offered from observation is a guess that average Collins availability over the last decade has been between two and three boats.

Then, if your strategic policy indicates advantages from increasing submarine warfare capability, a doubling in your fleet size provides increased capacity with insurance against submarine sustainability remaining frustrating and expensive.

Annoyingly impure as this real-world approach may be, it may carry something of its own internal corrective. In practice, it will be impossible for the RAN to absorb 12 new submarines in a continuous flow. The acquisition process will have to be staged over several batches. In the process, real metrics on the operational effectiveness and availability of the future submarines will be assembled. That data will give a clearer idea of how many submarines Australia really needs.

Photo courtesy of Flickr user Defence Images.