Continuous at sea deterrent

One of the Navy’s four strategic submarines is always on patrol, ensuring a continuous at sea deterrent, 24/7/365, carrying the nation’s ultimate weapon somewhere in the Seven Seas. Today’s Vanguard-class submarines uphold a mission which began in the late 1960s – since April 1969 the Royal Navy’s ballistic missile boats have not missed a single day on patrol.

The United Kingdom's strategic nuclear deterrent is provided by the Vanguard-class submarine. The first Vanguard class submarine was launched in 1993 carrying Trident II D5 missiles and is now the cornerstone of our defence policy and significantly contributes to the Alliance's deterrent forces. 

The Royal Navy maintains an at sea deterrent with one of these submarines at all times. A credible nuclear deterrent depends upon the ability to threaten an assured and effective response to aggression. For the Royal Navy this is done through the Trident D5 Missile. 

Trident D5 Missiles 

The Trident II D5 missile has a range of over 4,000 nautical miles and an accuracy, which can be measured in metres. Each missile is technically capable of delivering up to 12 warheads, enabling a number of different targets to be engaged, and each Vanguard class submarine has 16 missile tubes. The missile is ejected from the submarine by high-pressure gas and only when it reaches the surface does the rocket system actually fire.

What we are doing

On patrol, 24 hours a day, seven days a week, every day of the year.

Why we are there

Deterring conflict and protecting the nation

Preventing Conflict

The Royal Navy’s presence on the world stage sends a powerful message that the UK is committed to global affairs and provides a stabilising influence. In this way we prevent conflict on the high seas and protect the flow of international trade on which our nation depends.  

Ready to fight

When diplomacy fails, the UK has to be ready to protect its interests and its allies. What’s more, as a member of NATO and the UN, the UK also acts to support the enforcement of UN resolutions and come to the aid of our allies. This is where the Royal Marines come in: we train to go where we’re needed – by sea, land or air – and deploy our forces with the aim of restoring peace.

Location Global

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