RFA Lyme Bay gets ready for mine hunting in Gulf

The Royal Navy is upgrading one of its support ships, RFA Lyme Bay, to become a mine hunting mothership. The service is also attempting to transform into a hybrid navy, hoping to offset some of its manpower challenges with autonomous systems. 

By Sam Cranny-Evans, editor of Calibre Defence, published on March 30, 2026. 

The Royal Fleet Auxiliary (RFA) Lyme Bay is to be kitted out with uncrewed mine hunting systems, according to a March 29 announcement. According to the Royal Navy, the Bay Class landing ship has been transferred to heightened readiness, following events in the Gulf. 

She is currently in Gibraltar being equipped with the mine countermeasures. “Lyme Bay will be able to store, prepare, deploy and recover a variety of autonomous and crewless technology, from underwater drones to minehunting boats,” the statement explains. 

The UK deploys a number of autonomous and uncrewed mine countermeasures including the REMUS remote submersible. In March 2025, the UK also took delivery of the maritime mine-counter measures (MMCM) uncrewed surface vessel (USV) from Thales. Developed in cooperation with France, the MMCM is stated to provide a sea mine detection rate of 99%. The Royal Navy has not specified what capabilities the RFA Lyme Bay will carry, but these are presumably some of the options.

• Thales delivers MMCM USV to French Navy – Calibre Defence
• HII’s ROMULUS USV progresses – Calibre Defence 

More broadly, the UK has been working towards the mine countermeasure mother ship concept for some time. It is an interesting concept, but not all agree on it as an approach. Some analysts feel that a dedicated vessel is more appropriate, and that uncrewed platforms don’t completely obviate the need for divers to get in the water. 

Calibre comment: The Royal (hybrid) Navy

The Royal Navy’s transition to a hybrid navy – with part of its combat capability coming from uncrewed platforms – is hoped to resolve its staffing issues. For some years now the service has struggled to maintain the crew levels needed to keep ships at sea. This has combined with many different maintenance challenges to limit the Navy’s ability to generate and sustain force. Measures like the upgrades to RFA Lyme Bay may help ease some of those challenges, but there are fundamental roles that are difficult to make autonomous. Anti-submarine warfare is one that presents itself quite prominently, requiring large vessels with powerful sonars to be successful. Uncrewed platforms can help, extending a network of sensors well beyond those organic to the ship. But the need to put large ships and their crews to sea will not diminish. So, this is an issue that the hybrid Navy will continue to grapple with. 

• Operation Epic Fury: How the Gulf’s allies have responded – Calibre Defence 
• UK shipbuilding plans may be at risk, deferring could cost £12.5 bn – Calibre Defence 

The change in posture and role are of course a response to the situation in the Gulf. Iran has deployed sea mines in the Strait of Hormuz, but its missile capability will likely prevent RFA Lyme Bay venturing into that region until it is considered safe. 

The lead image shows RFA Lyme Bay on exercise in 2025. Credit: PO Phot Jim Gibson, RNR/MoD Crown Copyright.