Royal Navy’s fifth Astute-class submarine readies for sea trials

HMS Anson represents the cutting edge of the United Kingdom's military capabilities.
HMS Anson represents the cutting edge of the United Kingdom's military capabilities.

HMS Anson, the latest UK Royal Navy (RN) Astute-class nuclear-powered attack submarine (SSN) to enter service, arrived at its home port at HM Naval Base Clyde, Faslane, Scotland for the first time on 22 February 2023, after sailing from submarine builder BAE Systems’ Barrow-in-Furness shipyard. The boat will now prepare for and conduct operator sea trials.

In an RN statement published when Anson sailed from Barrow, UK Secretary of State for Defence Ben Wallace said “HMS Anson will play a vital role in defending the UK, providing a competitive edge for decades to come.”

Anson was commissioned into RN service in August 2022, and is the fifth of a seven-boat class. The previous four Astutes entered service between 2010 and 2020. The last two boats are both in build in Barrow.

The 7,800-tonne, 97 m long Astute-class SSNs carry the UK’s sea-based conventional land-attack capability, in the form of the Raytheon Block IV Tomahawk sea-launched cruise missile. To support the anti-submarine warfare (ASW) and anti-surface warfare (ASuW) roles, they are fitted with the BAE Systems Spearfish heavyweight torpedo. Up to 38 missiles and torpedoes can be carried in an Astute boat’s weapons stowage compartment. ASW capability is delivered also through the Thales 2076 integrated sonar suite, which combines bow, fin, flank, and towed arrays.

In addition, the Astute boats are designed to support intelligence-gathering operations, to deploy special forces, and to operate and work with uncrewed underwater vehicles.

While the UK now awaits the arrival of the last two Astutes, a debate has re-surfaced regarding whether the seven-boat force level should be increased in the face of growing threats in the underwater domain. At Anson’s commissioning ceremony back in August, Defence Secretary Wallace told the UK’s Daily Telegraph newspaper that he was commissioning a review within the navy to determine if the UK has the right force structure balance between submarines and surface forces, given that submarines are likely to play an increasingly critical role in dealing with future threats. That review is forming part of the UK’s wider refresh of its 2021 ‘Integrated Review’ of defence and security policy.

by Dr. Lee Willett