https://modmedia.blog.gov.uk/2015/05/21/update-on-nuclear-security/

Update on Nuclear Security

There has been continued coverage of the submariner who published criticism of Britain’s nuclear deterrent. The Royal Navy would like to reiterate that we take the operation of our submarines and the safety of our personnel extremely seriously.

We continue to fully investigate the circumstances of this issue and Ministers will update Parliament at the earliest opportunity.

Royal Navy Vanguard Class submarine HMS Vigilant returning to HMNB Clyde after her extended deployment. The four Vanguard-class submarines form the UK's strategic nuclear deterrent force. Each of the the four boats is armed with Trident 2 D5 nuclear missiles. Like all submarines the Vanguard Class are steam powered, their reactors converting water into steam to drive the engines and generate electricity.
Royal Navy Vanguard Class submarine HMS Vigilant returning to HMNB Clyde after her extended deployment.
The four Vanguard-class submarines form the UK's strategic nuclear deterrent force. Each of the the four boats is armed with Trident 2 D5 nuclear missiles. Like all our submarines, the Vanguard Class are steam powered, their reactors converting water into steam to drive the engines and generate electricity.