A new report was presented in parliament on Monday predicting that rapid technological progress in underwater drone technology and sensors could eventually make it impossible to hide big submarines like those intended to carry the UK’s Trident nuclear missiles.

The question of whether new technologies could one day make the deep oceans ‘transparent’ is emerging as a hotly-contested technical debate ahead of the Commons vote on the Successor programme, the replacement for the current fleet of four 20-year old Vanguard submarines.

The Commons defence committee has written to the defence contractors BAE and Babcock asking for an assessment of “whether new technologies, for example underwater drones, are being developed which could accurately detect and track submarines”, and therefore rob them of their defining advantage, stealth. Which is a little like writing to your tailor asking for his guarantee your suit will make you look sharp for all time.

The new report, by the British American Information Council BASIC, an independent security think-tank, says that advances in underwater drone and sensor technology will in the future make it impossible to hide a ‘boomer’, a big missile submarine, in the deep ocean, which - if not transparent - will be a great deal less opaque than it is now. The report is called: The Inescapable Net: Unmanned Systems in Anti-Submarine Warfare, and this is its bottom line:

In the past, submarines have enjoyed the luxury of hiding in empty seas. In the future, those seas are likely to be increasingly crowded with networked drones, a net of eyes and ears which no submarine can escape.



The report is written by a science journalist specialising in military technology, David Hambling, who has done a survey of the frantic work going on around the world on the boundaries of anti-submarine warfare (ASW). Last year I went to Nato’s Centre for Research and Maritime Experimentation in La Spezia, to look at progress on ASW drones and gliders. Hambling casts his net wider and addresses parallel research in China which appears to be a market leader in the field. The Chinese are looking at new forms of propulsion and navigation for underwater gliders and ‘robotic fish’, which operate in man-made shoals, capable of putting on a burst a speed when chasing a target.

In the US, Hambling looks at the navy’s work on Low-Cost UAV Swarming Technology (LOCUST), aimed at flying thirty drones operating in synch without invidual control by this summer. “Such swarms are capable of searching large areas autonomously, making them well suited for ASW operations,” he says.

Then there are SQUIDS – “Superconducting Quantum Interference Devices” – which are sensors delicate enough to measure the tiny magnetic fields generated in the brain. SQUIDS have up to now mainly been used in medicine. It was not possible to cart them about because they needed to be cooled with liquid nitrogen, but now micro-cyrogenic coolers are available so SQUIDS can be mounted on small drones and sent underwater.

None of these developments, as they stand, mean that ‘boomers’ are going to become visible overnight, but the BASIC argument is that, given the exponential nature of technological change, it would be the height of wishful thinking to spend over £40 billion on four new submarines that would only enter service in the 2030’s, by which time they could be a dozen ways to track them in the ocean’s depths.

The polar opposite point of view is put forward by two former Labour defence secretaries, John Hutton and George Robertson, who argued:

Every decade for at least the past 50 years predictions have been made that space-based or other non-acoustic sensors will turn the oceans “transparent”, thereby rendering submarines of all types vulnerable to detection, location and attack. Physics is a tough master however, and the oceans remain opaque. While we cannot rule out an eventual breakthrough, we are confident that the Successor class of Trident subs will be able to hide in the deep ocean, providing Britain with a powerful, invisible, secure and invulnerable deterrent for many years to come.

This line of reasoning is basically saying that as it hasn’t been invented yet, it won’t be invented in the future, which is hardly a rousing ethos for scientific endeavour, particularly in a field where the obstacles - in terms of visibility through the oceans - are not inherently insuperable. A more compelling argument for the pro-Trident side would perhaps be that if the UK is going to retain a nuclear deterrent, a submarine based variant will always be less vulnerable than land and air-based.

Just as ASW technology evolves, so will measures to counter that technology. At worst, the UK could resort to the ‘bastion’ strategy followed by Russia, to deploy ‘boomers’ under extensive air and sea protection to make them as invulnerable as possible. Ultimately, the same questions will remain: whether the UK should have nuclear weapons at all given their huge and indiscriminate destructive power and the unlikelihood of ever being used, and whether the country can afford to put so much reliant on a weapon whose reliability can henceforward never be taken for granted.

