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Maximising Australia’s submarine capability with a ‘high-low’ mix

submarine capability

‘High-low force structures establish a complementary force package and have typically been the domain of air combat systems – the rise of increasingly capable submarine platforms in the Indo-Pacific, combined with the operating environment and broader Navy force structure, requires a major rethink of Australias submarine force.

‘High-low force structures establish a complementary force package and have typically been the domain of air combat systems – the rise of increasingly capable submarine platforms in the Indo-Pacific, combined with the operating environment and broader Navy force structure, requires a major rethink of Australias submarine force.

Silently hunting below the waves, the vessels are increasingly lethal and difficult to detect – submarines are one of the great tactical and strategic levellers. Patrolling groups of hunter-killers and at-sea deterrence force structures serve to enhance the specialisation and increasing capabilities of contemporary navies.

The highly successful campaigns of terror conducted by the German Navy's 'wolf packs' of submarines during the Second World War to the tactical and strategic brinkmanship between ever more deadly American and Soviet nuclear submarines during the Cold War have set the stage for the 21st century's race for strategic undersea dominance.


As both great and regional powers scramble to design and build, or buy and introduce, the latest and most capable submarine platforms to ensure their continued dominance, maritime security and ability to deter potential adversaries, Australia's changing strategic environment has raised questions around the survivability, cost and capability of the Royal Australia Navy's ageing Collins Class submarines and the relevance of Australia's future Attack Class submarines. 

Recently, renowned Australian strategic policy thinker Hugh White presented a radical idea for shaping the future of the Royal Australian Navy and the submarine force in particular, as part of the nation's broader response to defending the nation in the era of an increasingly competitive Indo-Pacific region. A core focus of this was White's insistence on shifting the bulk of Australia's naval manpower and materiel towards the submarine force – cancelling major acquisition projects including the $35 billion SEA 5000 Hunter Class and sale of the Canberra Class vessels.

White recognises both the tactical and strategic advantages provided by submarine forces – this has been reinforced in recent days following conversations surrounding the launch of the first French nuclear-powered Barracuda Class fast attack submarine, the Suffren and conversations regarding Australia's pursuit of nuclear-powered submarines.

Further complicating the strategic debate is the growing number of increasingly advanced and highly capable submarines expected to be operating in the Indo-Pacific by the 2020s – which will directly impact the tactical and strategic capability of Australia's ageing Collins Class vessels prior to the introduction of the first Attack Class vessel, HMAS Attack, in the mid-to-late 2030s. 

Enter the realm of the 'high-low' capability mix. Traditionally reserved for the difference between air superiority/air dominance fighter aircraft and multi-role fighter aircraft – both designed to serve unique, yet complementary roles within tactical and strategic force structures – accordingly, a 'high-low' capability mix is equally relevant for developing a complementary and highly adaptable submarine force. 

Long-range escort submarines 

The basis of Australia's future Attack Class submarines, the Barracuda Class, were designed as long-range hunter-killer and convoy escort submarines – fitting into a complementary role supporting French carrier and amphibious formations through traditional anti-submarine and anti-surface warfare operations in conjunction with solo long-range anti-submarine and anti-surface warfare and land attack as secondary mission roles.

It is expected that Australia's Attack Class submarines will serve a similar role – escorting major maritime task groups, led by the Canberra Class landing helicopter docks (LHD) or the Hobart and Hunter Class destroyers and frigates, respectively. This traditional escort role is only part of the expected role of the Attack Class vessels – with the long-range, endurance and payload supporting an element of broader strategic deterrence, intelligence, surveillance and reconnaissance roles. 

However, Australia's Attack Class submarines are not without their contention and operational challenges, as has been raised by commentary in recent days – namely the continuing challenges to crew the vessels, combined with unit cost, delivery time frame and technology capability, particularly of the planned lead-acid battery packs. 

Additionally, the size of the Attack Class, compared with vessels already in operation, like the Kilo, Scorpene, Type 209 and Type 212/214 variants in the Indo-Pacific serves to limit the operational flexibility of the submarines, particularly in the comparatively shallow, narrow and congested strategic waterways and chokepoints throughout south-east Asia. 

It is important to elaborate – the Attack Class are a critical component of Australia's future naval and broader defence capabilities, however the planned dozen vessels is a number based on an arbitrary decision regarding force structure and posture identified in the 2013 Defence White Paper and subsequently the 2016 Defence White Paper, and requires significant discussion about suitability.  

Sea control submarines 

Recognising the growing concerns about the Attack Class vessels, combined with the age, capability limitations and the heavy crew requirements of the Collins Class vessels, consideration about introducing a fleet of smaller, yet complementary conventional submarines optimised for sea control, maritime interdiction, shallow water operations and anti-submarine and anti-surface warfare operations serves as an attractive option. 

There are a number of proven, highly capable alternatives that can serve in the niche role – including the Naval Group designed Scorpene Class in service with Malaysia, India and Brazil, the Type 212/214 and Type 218SG submarines designed and built by SEA 1000 bidder ThyssenKrupp Marine Systems (TKMS) or the evolved Gotland Class variant – each of which are optimised for shallow water operations, sea control, maritime interdiction and anti-submarine and anti-surface warfare operations.

Additionally, these designs all combine comparatively small crew requirements, with advanced air independent propulsion (AIP) technology, advanced heavy weight anti-ship and anti-submarine weapons systems combined in a compact package with long-range and high endurance enabling the vessels to support long-range tactical and strategic sea control and/or deterrence operations. 

Accordingly – a fleet of joint-locally built, forward deployed vessels would serve not only to bridge the capability gap between the Collins and arrival of the Attack Class submarines while also providing Australia with a credible, bespoke and scaleable force structure to respond to the rapidly evolving geo-strategic challenges of the Indo-Pacific. 

Your thoughts  

As an island nation, Australia is defined by its relationship and access to the ocean, with strategic sea-lines-of-communication support over 90 per cent of global trade, a result of the cost effective and reliable nature of sea transport. Indo-Pacific Asia is at the epicentre of the global maritime trade, with about US$5 trillion worth of trade flowing through the South China Sea and the strategic waterways and choke points of south-east Asia annually.

While the Indian Ocean and its critical global sea-lines-of-communication are responsible for more than 80 per cent of the world's seaborne trade in critical energy supplies, namely oil and natural gas, which serve as the lifeblood of any advanced economy.

Submarines are critical to the nation's ability to protect these strategically vital waterways and key naval assets, as well as providing a viable tactical and strategic deterrent and ensure the nation's enduring national and economic security – recognising this, the previously posed questions will serve as conversation starting points.

However, given the geographic area of responsibility Australia will become increasingly responsible for and dependent on, is the RAN and the recapitalisation and conventionally-focused modernisation program for Australia's submarine fleet enough for Australia to maintain its qualitative and quantitative lead over regional peers?

Traditionally, Australia has focused on a platform-for-platform acquisition program – focused on replacing, modernising or upgrading key capabilities on a like-for-like basis without a guiding policy, doctrine or strategy, limiting the overall effectiveness, survivability and capability of the RAN. Let us know your thoughts in the comments section below, or get in touch with This email address is being protected from spambots. You need JavaScript enabled to view it. or This email address is being protected from spambots. You need JavaScript enabled to view it..  

Stephen Kuper

Stephen Kuper

Steve has an extensive career across government, defence industry and advocacy, having previously worked for cabinet ministers at both Federal and State levels.

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