Around 15 years from now, the Royal Navy’s newest submarine will come into service.

The first Dreadnought, one of four new ships currently under construction at an estimated cost of £31 billion, will replace the existing Vanguard class that has defended the UK since 1994. Details are in short supply, but here’s what we know so far.

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Previously known as the Successor program, Dreadnought will consist of four submarines. The first of the Dreadnought class will come into Royal Navy service in the early 2030s.

The Dreadnought class will carry the Trident nuclear missiles, Britain’s nuclear deterrent. The measure to renew Trident passed in the House of Commons in July 2016 by a majority of 355 votes.

The Dreadnought name has plenty of history. Nine Royal Navy vessels have already carried the moniker. The HMS Dreadnought of 1906 (below) brought in a huge shift in naval warfare as, amongst other features, it was the first battleship to have a main gun battery. Ships named Dreadnought also sailed during the Spanish Armada in 1588 and the Battle of Trafalgar in 1805.

Britain’s first nuclear submarine was also called Dreadnought and was launched by the Queen in 1956 (bottom picture) from the same yard in which the current class is being constructed.

Work on the concept design has been underway since 2007, according to BAE, while the Government approved the business case in 2011.

HMS Dreadnaught - REX Pictures

The Dreadnought class submarines will be built at BAE System’s site in Barrow-in-Furnace, Cumbria.

In October 2016, the Ministry of Defence committed £1.3 billion to the project to get building work underway. The total cost is estimated at £31 billion.

It’ll be the first Royal Navy British submarine with lighting capable of simulating night and day.

The Dreadnought will be 152.9 feet long, which is around the size of 3 Olympic swimming pools, almost ten feet longer than the V-boat.

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It’s also the largest ever built for the navy, displacing 17,200 tonnes, that’s 1,300 more tonnes than Vanguard

While details are still vague on the specifics, the Dreadnought will manufacture its own fresh oxygen and water.

There’s 42.5km of piping and 20,000 cables (347km). There’ll also be 13,000 electrical items on board the ship.

First Dreadnought submarine maiden voyage 1960

The UK Defence Journal offers insight into Dreadnought’s Common Missile Compartment. It writes: “While details remain sketchy at best regarding the Dreadnought class, one of the key features the new boats will have is a Common Missile Compartment (CMC). CMC aims to define the missile tubes and accompanying systems that would be used to launch new ballistic missiles, successors to the current Trident II/ D5 missile fleet used by the USA and Britain.”

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There’s room on board for 130 crew members; three of whom are chefs.

It’s also the first Royal Navy submarine that will offer separate quarters, washing facilities and toilets for male and female crew members.

According to the 2010 Strategic Defence and Security Review, each of the Dreadnoughts will carry eight operational missiles and no more than 40 warheads.

Whether you’re a bookworm or a gym-rat (or both), the Dreadnought has you covered. There’ll be a classroom and study area, and also modern gym facilities. A treadmill is useful as crewmembers can’t exactly go for a long run on a submarine.

More than 2,600 people are currently working on Dreadnought, with BAE predicting up to 7,800 employed each year, throughout the 2020s

‘Delivery Phase 1’ commenced in October 2016 with the cutting of the first steel. However, although there was union dismay over reports that French, not British, steel would be used in the construction, the MoD responded by confirming British steel would be used ‘in the process’.

Several hundred suppliers will be involved, 95% of whom will be from the UK.

Dreadnought submarines are being designed to meet and deter security threats well into the 2050s.

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Credit: BAE Systems