Plymouth’s leading-edge submarine manufacturer M Subs Ltd has secured a £1million Government contract to build a prototype robot sub for the Royal Navy.

Business Live broke news of the deal in 2019 but now it has been officially confirmed by the Ministry of Defence.

And if initial tests of the sub are successful, up to £1.5million more could be made available by the MoD to further test the unmanned vehicle.

Measuring about 30ft in length, the autonomous submarine is significantly larger than other robot subs used for beach reconnaissance, allowing it to operate at a range of 3,000 nautical miles.

The current submarine that will be converted into a robot sub for the Navy by M Subs

The vessel is being built as part of the MoD’s Defence and Security Accelerator (DASA) project.

The first phase of what is dubbed the Developing the Royal Navy’s Autonomous Underwater Capability programme, run jointly with the Royal Navy and Defence Science and Technology Laboratory (Dstl), will see an existing crewed submersible refitted with autonomous control systems.

If initial testing is successful, more funding will be forthcoming, making it the largest joint contract awarded as part of a DASA tender.

Estover-based M Subs had a record £10million turnover in 2019 and has grown from 10 employees in 2010 to more than 60, with further jobs being created.

M Subs Ltd's Plymouth factory

Paddy Dowsett, from M Subs, said: “We are thrilled to be awarded this contract through DASA, and have the opportunity to work with defence scientists and experts to develop new and advanced capabilities for the Royal Navy.

“This funding will allow the Royal Navy to better understand their future roles and for us to remain at the forefront of extra-large uncrewed underwater vehicles (XLUUV) design and manufacture in Europe.”

Currently, smaller autonomous and remotely piloted submarines are unable to undertake all the tasks of larger crewed submarines.

XLUUVs are especially adept at covert intelligence gathering. They can leave their dock autonomously and secretly move to the operational area without any embarked crew for up to three months.

They are also able to sense hostile targets and report their findings back to the station, making them an important barrier for anti-submarine warfare.

Defence Minister Jeremy Quin said: “Submersible autonomous vessels have huge potential and this project could be a game-changer for the UK’s underwater capability, taking our submarine service to the next level.

“I am pleased that this funding supports M Subs Ltd, a UK-based company committed to innovation and research in the autonomous sector.

“This is a key example of how defence is doing more than ever before to give industry the opportunity to research innovative new technology.

Admiral Tony Radakin, First Sea Lord, announced the contract at the Underwater Defence and Security Symposium in Southampton.

Laura Hudson at M Subs' Plymouth factory. She is the firm's head of finance

The First Sea Lord noted how the MoD wants to increase its presence in the underwater battlespace and is exploring the use of extra-large uncrewed underwater vehicles (XLUUV) for surveillance, reconnaissance, and anti-submarine warfare operations.

He said: “I am enormously excited about the potential for remotely piloted and autonomous systems to increase our reach and lethality, improve our efficiency and reduce the number of people we have to put in harm’s way.

“These XLUUVs are at the forefront of underwater systems technology; UK technological developments such as this will be key to the Royal Navy maintaining its battle-winning edge in the underwater environment.”

DASA delivery manager Adam Moore said: “DASA’s involvement is enabling this technology to advance at a much quicker pace and to deliver new capabilities to the Royal Navy years earlier than otherwise possible, making sure the UK stays ahead of our adversaries.

How to contact William Telford and Business Live

Business Live's South West Business Reporter is William Telford. William has more than a decade's experience reporting on the business scene in Plymouth and the South West. He is based in Plymouth but covers the entire region.

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“Not only will this enhance the UK’s strategic advantage but also boost UK prosperity by supporting small and medium-sized companies like M Subs in Plymouth.”

M Subs has just made 30-year-old finance chief Laura Hudson a director. She joins the board at the firm, based at the Sisna Park Road business park in north Plymouth, at a time when it is “smashing it” and eyeing growth.

The company is recognised as the UK’s leading manufacturer of military submersibles and has already completed a manned platform, the Dry Combat Submersible (DCS), for the United States of America’s Special Forces Command. It completed successful trials in the waters around Plymouth in 2019.

M Subs has also spun out another firm called Marine AI, which has already become a success, working with tech giant IBM and looking to grow into its own base in another part of Plymouth.