Three of four UK nuclear subs at sea simultaneously

Three of the United Kingdom's four nuclear deterrent submarines are currently operating at sea concurrently. The Times reported the deployment on Wednesday, marking the first instance of such a simultaneous launch in five years. The newspaper noted that at least one of the vessels is armed with ballistic missiles carrying nuclear warheads.

The specific boats at sea are HMS Vanguard, HMS Vigilant, and HMS Vengeance. All three belong to the Vanguard class. HMS Victorious, the fourth submarine in the fleet, is currently in maintenance. A navy source described the deployment as unusual but provided no further details on the operational status of the ships.

Standard Royal Navy procedure requires at least one submarine to remain on patrol at all times to guarantee security. Navy Lookout, an independent publication, states that a missile-carrying submarine has been at sea continuously since 1969. The second vessel is likely preparing to relieve the boat on patrol, while the third is probably conducting sea trials or work-up activity.

Long-duration patrols are not uncommon for the fleet. HMS Vanguard spent 200 days at sea last year. That duration fell one week short of the record 207 days set by HMS Victorious in 2021.

The concurrent deployment has raised questions about Britain's defence posture. Defence Secretary Wes Streeting warned last week that the country must be prepared for war. Writing in The Telegraph, Streeting stated that Britain must be ready within 1,000 days. He added that by 2030, opposing force strength and war economies could reach a level capable of initiating an attack.

A defence ministry spokesperson described the nuclear deterrent as the cornerstone of national security. The spokesperson noted that the UK is the only European ally to commit its nuclear deterrent to NATO's defence, meaning all allies benefit from the capability.

This activity coincides with recent diplomatic and military moves. British and French fighter jets completed their first joint exercise involving France's airborne nuclear capability last week. French Armed Forces Minister Catherine Vautrin said that independent nuclear forces do not preclude coordination. Streeting stated that the UK and France stand together in their commitment to European security.