Royal Navy Adapts Subsea Construction Vessel for National Security Role

RFA proteus
Courtesy Royal Navy

Published Oct 11, 2023 8:05 PM by The Maritime Executive

In order to ensure the security of Britain's subsea infrastructure, the Royal Navy has inducted a refitted subsea construction vessel into its fleet. 

The newly-renamed RFA Proteus will be a mother ship for ROV operations, and will bring offshore oil and gas capabilities into government service. The formerly-civilian vessel will be crewed by 26 civilian mariners from the Royal Fleet Auxiliary, along with 60 Royal Navy mission specialists. 

“It is a huge honour and responsibility for the Royal Fleet Auxiliary to be charged with crewing and operating RFA Proteus and delivering her unique, sovereign capability," said Commodore David Eagles, head of the RFA. 

Proteus started her life in 2019 as the subsea construction and inspection vessel Topaz Tangaroa. She was built by Vard for P&O, and the design emphasized seakeeping ability; this played a role in her selection for Royal Navy service, and she was acquired earlier this year. She completed her Royal Navy overhaul and commissioning at the Cammell Laird yard in Birkenhead. 

Proteus is the second of two offshore vessels that the Royal Navy purchased for subsea-security applications. The former platform support vessel RFA Stirling Castle was acquired early this year and will be used for mine countermeasures, serving as a mother ship for the Royal Navy's unmanned minehunting systems. The Royal Navy says the aim is to speed up searches and keep crewmembers away from mine hazards. 

The additions to the fleet are a response to a real security need. British Prime Minister Rishi Sunak made the acquisition of subsea surveillance vessels a top priority after the attack on the Nord Stream pipeline in the Baltic last year. While the perpetrator has not been identified, independent observers have noted frequent signs of Russian surveillance near the UK's subsea infrastructure, including wind farm power transmission cables. The apparent sabotage of the Balticconnector pipeline last weekend has also highlighted the vulnerability of subsea assets to covert attack.