PT boats combined high speed, swarming tactics and an arsenal to level the playing field against larger and more expensive surface ships during the Pacific War. The shift towards the contested waterways of the Indo-Pacific, combined with advances in technology, provides the opportunity for developing a potent new form of sea control.
Maritime warfare is evolving at a similar pace to that of other domains, and the rise of unmanned technologies, advanced sensors and increasingly cost effective submarines and small surface warships is shifting the balance of power away from fleets of destroyers, frigates and aircraft carriers.
The importance of maritime choke points is enhancing the lethality of these platforms, giving rise to a new era of asymmetric naval warfare particularly in the Indo-Pacific where maritime choke points like the Straits of Malacca, Lombok and Sunda challenge traditional maritime protection doctrine.
Enter the realm of maritime asymmetric warfare, which serves as a powerful balancing force between two actors defined by significantly different levels of power and whose strategy and tactics differ significantly. Asymmetric warfare is typically defined as a form of guerrilla warfare, insurgency driven and as is increasingly common in the modern era, a form of terrorism.
Throughout the Second World War, both the Allies and Axis powers used asymmetric warfare in terms of submarine raiding and the Pacific theatre's PT boats to harass Japanese surface warships and convoys until the might of the US and broader allied navies could be brought to bear – the advent of the PT boats and the subsequent swarming tactics were used with relative success.
While the increasing proliferation of highly capable conventional submarines, like the Russian Kilo Class and the various variants operated by nations throughout the Indo-Pacific, Singapore's existing Archer and Challenger Class submarines, French Scorpene Class and Australia's Collins Class, all serve as key asymmetric force multipliers capable of directly influencing the tactical and strategic calculations of nations dependent on the critical maritime choke points in the region.
While submarines represent the high-end of the maritime asymmetric warfare calculations, fast, nimble and light torpedo and anti-ship missile carrying vessels supported by dedicated or pseudo-motherships are potent, cost-effective ways of establishing sea control while also providing close-in support for larger, power projection focused naval task groups.
A modern PT-109?
Essential to the success of the high-tempo, hit and run tactics implemented by the US Navy during this period was the relative small, fast and inexpensive PT boat. Originally conceived as anti-ship weapons, building on the early success of the original destroyer type platforms, PT boats were publicly credited with successfully sinking several Japanese warships during the period between December 1941 and the fall of the Philippines in May 1942.
There are few international examples of vessels that fit the role of a contemporary PT boat, with most contemporary peer or near-peer competitor navies focused on establishing solely 'high end' capabilities – however, Australia's unique operating environment, combined with the changing strategic environment, requires the joint development of a 'high' and 'low' capability mix of naval capabilities.
Taiwan is one such nation that has developed a credible contemporary to the PT boat. The Tuo Chiang Class corvettes have a top speed of 40 knots when fully armed with a suite of advanced, domestically manufactured anti-ship and anti-air cruise missile systems designed to counter the growing threat posed by the Chinese armed forces, namely the Chinese Navy and its growing submarine and surface warfare capabilities.
Looking further abroad, the Norwegian Navy has developed a modest fleet of superfast, stealth 'missile corvettes' in the Skjold Class, which weigh in at 274 tonnes fully loaded with a maximum speed of 60 knots (110km/h). The vessels incorporate a relatively potent arsenal for a vessel of their size, including eight Kongsberg Naval Strike Missiles and a 76mm mounted gun.
Australia's fleet of F-35s are expected to be equipped with a modified variant of the Naval Strike Missile, the joint Norwegian and Australian developed Joint Strike Missile. Additionally, the Skjold Class has a relatively small crew requirement of about 14 and can be equipped with both Link 11 and Link 16 to better disseminate information between a range of ADF assets as part of the broader 'joint force'.
Australia's Arafura Class is designed to replace approximately 26 vessels across four warship classes currently in service with the Royal Australian Navy, including the Armidale, Huon, Leeuwin and Paluma Class vessels, while also providing additional support for deployed amphibious task groups centred on a Canberra Class Landing Helicopter Dock (LHD), and the future Supply Class fleet auxiliaries are designed to operate either independently or as part of a larger task group.
Accordingly, the Arafura Class could serve as a pseudo-mothership for small hunter-killer groups of the Australian Skjold Class vessels to support Australia power projection and sea control operations, while also supporting and protecting larger naval assets like the Canberra Class in high intensity operations – effectively establishing a 'high' and 'low' capability mix for the Royal Australian Navy.
Designed to hunt in packs, these highly capable vessels serve to mimic the wolf pack tactics of the German U-Boats, maximising the offensive capabilities of a force limited by domestic and broader international political realities. These platforms leverage their cost effective nature, combined with swarming tactics and the increasing capability and interoperability afforded by relatively cheap missile systems, to overwhelm the defences of multibillion-dollar warships and unarmed tankers.
The combination of these multi-domain capabilities affords nations and non-state actors to level the tactical and strategic battlefield when competing with middle and superpowers capable of fielding a range of costly, yet advanced, integrated and multi-domain power projection capabilities – doing so often forces these larger nations to consider their options, bringing them to the negotiating table and effectively nullifying their traditional strengths.