A 12-tonne fishing vessel is anchored three kilometers from Port Adelaide. A small team gathers at the miniature submarine, operates the controls, loads the explosives and releases them into the water. The underwater drone uses sensors and sonar to navigate to a pre-programmed target: a single, narrow harbor channel responsible for the state’s main fuel supply.

You can guess the rest. A blockade, an accident, an explosion; Any of these could spell disaster for Australia, which does 99% of its trade by sea and imports more than 90% of its fuel.

Australia’s 34,000 kilometers of coastline will face significant threats in the future as unmanned submarines, or “unmanned underwater vehicles” (UAVs), become cheaper, more common and more sophisticated.

What can be done? Our assessment, supported by workshops attended by experts from across Australia, shows that the same technologies could also help our maritime safety if we incorporate them into our planning going forward.

Battle on the sea bed

Australia is not alone in its growing concern about submarine safety. France launched the Seabed Warfare Strategy to combat autonomous underwater maritime threats in 2022. In February 2023, NATO established an underwater infrastructure coordination group in response to the September 2022 Nord Stream sabotage.

Relatively small and cheap aerial drones played a major role in the war in Ukraine. On a smaller scale, underwater drones have also enabled Ukraine to launch asymmetric attacks on Russian forces.

Modern drones can be used in intelligence, surveillance, reconnaissance, mine defense, anti-submarine warfare, electronic warfare, development of underwater sensor networks, and special operations, among others.

But their capabilities will likely expand. China’s Haidou-1 project descended to a record depth of 10,908 meters.

China’s Haiyan underwater glider holds the endurance record among unmanned submarines, covering a distance of 3,600 km in 141 days in the South China Sea. Russia boasts of having a prototype of a nuclear-powered underwater drone, but some analysts doubt it actually exists.

Countries are also developing broader programs to control underwater marine areas.

For example, the advanced underwater warfare system proposed by the United States includes a network of fixed underwater stations capable of deploying defensive and offensive unmanned aerial vehicles. In the South China Sea, China is building a “Great Underwater Wall” of ships, bases, and drones (both above and below the surface) to control the area and make it difficult for foreign navies to operate in international waters.

A new era of warfare at sea?

Some analysts argue that these events signal the beginning of a new era in naval warfare. Others argue that autonomous maritime systems could become superior to manned vehicles in national defense as they become cheaper and more efficient: By 2052, one estimate suggests, unmanned ships could make up the majority of the U.S. Navy.

The emergence of maritime drones could facilitate the further growth of hybrid or “grey zone” approaches to conflict that avoid open warfare, minimize casualties, and can impose heavy costs on adversaries. In this context, unmanned marine vehicles can offer states a dubious way to take aggressive actions to achieve their goals without crossing the threshold of war.

In other words, unmanned submarines can cause obvious accidents and other actions that cannot be attributed to those who initiated them. In this context, it is useful to quote the French strategy of waging war on the seabed:

An attack on the underwater part of submarine cables is a potential cause of action, the possibilities of which range from a “convenient” accident in the coastal zone to a deliberate act of war. In this regard, the internal features of the seabed make it an ideal theater for incomprehensible actions in the “gray zones”.

A way forward for Australia

Our new research examined the threat posed by autonomous unmanned underwater vehicles to Australian trade.

Together with colleagues from RMIT Cyber ​​Security Research and Innovation Centre, Charles Darwin University and WiseLaw, we have held workshops with representatives from government, the Royal Australian Navy, defence, industry and academia. Today, we see a growing conflict between efforts to protect ocean commerce and critical underwater infrastructure and more forward-looking strategies to develop next-generation maritime defenses.

Under the AUKUS security pact, Australia has commissioned the UK and US to purchase and build nuclear-powered submarines and is seeking to purchase and develop new systems “with additional underwater capabilities”. It’s a good start, but the size of the purchase raises concerns it will be too taxing for the Australian military.

Australia also participates in exercises such as Autonomous Warrior to test new maritime defense systems. However, these exercises underestimate the threats that underwater drones could pose to maritime commerce in the future.

One of the results of our workshops is that mines are seen as a new problem. Explosive drones (even commercially available ships carrying improvised explosive devices) can delay commercial ports and shipping, jam maritime assets, or disrupt maritime shipping lanes. This will cause delays, lost profits and increased insurance premiums.

A set-it-and-forget-it type of weapon, mines pack a huge punch because they can inflict a lot of damage at low cost. Finding and neutralizing them is difficult and expensive.

Currently, Australia is largely protected from the threat of underwater drones from afar. Current battery and communications technology means drones must be deployed relatively close, and Australia’s maritime environment will make this difficult. However, technology is developing rapidly. The time available to the Australian Department of Defense to solve the problem of unmanned underwater vehicles is running out. Source