The Royal Navy Submarine Service is one of the five fighting arms of the Royal Navy. It is sometimes known as the Silent Service, as submarines are generally required to operate undetected.

The service operates six fleet submarines (SSNs), of the (with one further Astute-class boat currently under construction), and four ballistic missile submarines (SSBN), of the . All of these submarines are nuclear powered.

The Royal Navy's senior submariner was for many years located at in Hampshire. It moved from Dolphin to the Northwood Headquarters in 1978. The Submarine School is now at at Torpoint in Cornwall.

History

In 1900 the Royal Navy ordered five submarines from Vickers Shipbuilding and Engineering of Barrow-in-Furness, designed by Electric Boat Company. The following year the first submarine, , was launched, and the navy recruited the first three officers for the Submarine Service, Lieutenants Stephen Bowle-Evans (N) and Forster Delafield Arnold-Forster (T), under Reginald Bacon as Inspecting Captain of Submarines, on the 20th of August 1901. They were shortly thereafter joined by Lieutenant John Alfred Moreton in early October 1901.

At the beginning of World War I it consisted of 168 officers, 1,250 ratings, and 62 submarines. During the war it was awarded five of the Royal Navy's 14 Victoria Crosses of the war, the first was to Lieutenant Norman Holbrook, commanding officer of , for passing through minefields to sink the Ottoman warship Mesudiye.

Late in the war, the Royal Navy introduced the large K-class submarines. In order to be fast enough to operate alongside the battlefleet, they used steam propulsion while surfaced. En route to a training exercise with the fleet in a disaster, afterwards nicknamed "the battle of May Island", two K-class submarines were sunk, with death of most of their crew, and three more and a light cruiser damaged.

Second World War At the start of the war, the Royal Navy had 60 submarines with another nine under construction. By August 1945 a further 178 had been commissioned and 76 had been lost to all causes, the majority of the losses in the Mediterranean. In the Mediterranean (during the Siege of Malta), British U-class submarines began operations against Italy as early as January 1941. Larger submarines began operations in 1940, but after 50% losses per mission, they were withdrawn. U-class submarines operated from the Manoel Island Base known as HMS Talbot. Unfortunately no bomb-proof pens were available as the building project had been scrapped before the war, owing to cost-cutting policies. The new force was named the Tenth Submarine Flotilla and was placed under Flag Officer Submarines, Admiral Max Horton, who appointed Commander George Simpson to command the unit. Administratively, the Tenth Flotilla operated under the First Submarine Flotilla at Alexandria, itself under the admiral commanding in the Mediterranean, Andrew Cunningham. In reality, Cunningham gave Simpson and his unit a free hand. Until U-class vessels could be made available in numbers, British T-class submarines were used. They had successes, but suffered heavy losses when they began operations on 20 September 1940. Owing to the shortage of torpedoes, enemy ships could not be attacked unless the target in question was a warship, tanker or other "significant vessel". The flotilla's performance of the fleet was mixed at first. They sank of Italian shipping; half by one vessel, the submarine . It accounted for one Italian submarine, nine merchant vessels and one Motor Torpedo Boat (MTB). The loss of nine submarines and their trained crews and commanders was serious. Most of the losses were to mines. On 14 January 1941, U-class submarines arrived, and the submarine offensive began in earnest.

One of the most famous Mediterranean submarines was , commanded for its entire career by Lieutenant-Commander Malcolm Wanklyn. He received the Victoria Cross for attacking a well-defended convoy on 25 May 1941 and sinking an Italian liner, the . In her 16-month operational career in the Mediterranean, before she was lost in April 1942, Upholder carried out 24 patrols and sank around 119,000 tons of Axis ships – 3 U-boats, a destroyer, 15 transport ships with possibly a cruiser and another destroyer also sunk. Upholder probably struck a mine on 13 April 1942.

On 8 September 1944, C-in-C Mediterranean ordered that the submarine base at La Maddalena be closed, and that Tenth Flotilla be disestablished and the submarines be incorporated into the First Submarine Flotilla at Malta.

Cold War The submarine force was cut back after the end of the war. The first British nuclear-powered submarine was launched in 1960, based around a U.S.-built nuclear reactor. This was complemented by the from 1966, which used a new British-built Rolls-Royce PWR1 reactor. The UK's strategic nuclear deterrent was transferred to the Royal Navy from the Royal Air Force at midnight on 30 June 1968, i.e. 1 July. The ballistic missile submarines (SSBNs) were introduced to carry out this role under the Polaris programme from 1968. These carried US-built UGM-27 Polaris A-3 missiles and were later replaced by the submarines and the Trident missile system from 1994.

In 1978 the Flag Officer Submarines double-hatted as NATO Commander Submarine Force Eastern Atlantic (COMSUBEASTLANT) part of Allied Command Atlantic, moved from HMS Dolphin at Gosport to the Northwood Headquarters.

made history in 1982 during the Falklands War when she became the first nuclear-powered submarine to sink a surface ship, the . and hunted the Argentine Navy carrier group Task Group 79.1 but did not engage.

At the end of the Cold War in 1989 the Flag Officer Submarines, who was also COMSUBEASTLANT, a rear admiral, commanded a fleet of 30 submarines which were grouped into four squadrons (First, Second, Third, and Tenth (SSBN)) at three bases.

Post Cold War

In May 1991 s and her sister returned to the submarine base in Gosport from patrol in the Persian Gulf flying Jolly Rogers, indicating successful actions.

In 1999 participated in the Kosovo Conflict and became the first Royal Navy submarine to fire a Tomahawk cruise missile in anger.

During Operation Veritas, the attack on Al-Qaeda and Taliban forces following the September 11 attacks in the United States, was the first Royal Navy submarine to launch Tomahawk cruise missiles against targets in Afghanistan. was also involved in the initial strikes. launched fourteen Tomahawks during the 2003 invasion of Iraq.

In 2011, HMS Triumph and Turbulent participated in Operation Ellamy. They launched Tomahawk cruise missiles at targets in Libya, firing the first shots of the operation.

In April 2016, The Sunday Times reported that Royal Navy submarines were to resume under-ice operations in the Arctic. Such operations have not taken place since 2007 after a fatal explosion on board . The crews of all seven active Royal Navy attack submarines will receive training on how to navigate below and "punch through" ice floes.

In 2018, there had been three near misses over four years between submerged Royal Navy submarines and civilian vessels due to "an insufficient appreciation of the location of surface ships in the vicinity", according to a Marine Accident Investigation Branch report.

For an extended period of time, the navy has had difficulty in attracting specialist staff into the nuclear submarine force, in part because of the long undersea patrols. In 2008 there were shortfalls of 28% in senior nuclear engineering officers, 23% in sonar and sensor operators, and 20% in nuclear weapons system junior ranks. In 2018, the National Audit Office highlighted the shortage of 337 skilled Royal Navy nuclear staff. In 2023, Chief of the Naval Staff Admiral Sir Ben Key said recruiting for the submarine service was still proving difficult and the service was in a "war for talent".

In December 2025, the former director of nuclear policy who led the 2010 Trident value for money review, Rear Admiral Philip Mathias, said the service faced an unprecedented situation, with record delays in building fleet submarines and "shockingly low availability” of submarines which had driven up patrol duration for crews to more than 200 days up from the 70 days during the Cold War. He highlighted that three Astute submarines had spent more than 950 days in maintenance outages and that had taken over 13 years to build, and called for Britain to pull out of the AUKUS programme to build 12 new nuclear submarines as "The UK is no longer capable of managing a nuclear submarine programme". In June 2026, The Daily Telegraph reported that all British attack submarines were in port awaiting maintenance and repair, other than the recently commissioned which was not yet ready to deploy.

The refuelling and refit of took from 2015 to 2022. The overrun of the maintenance by about four years had a major impact on Vanguard-class operations, causing other vessels in the class to have to operate extended-length Continuous at Sea Deterrent patrols, of up to 205 days (nearly 7 months) at sea compared to the previously generally planned 99 day patrols, impacting submariner retention and recruitment.

Perisher

'Perisher' (as the Submarine Command Course is better known) is a 24-week course all officers must take prior to serving as an executive officer on board a Royal Navy submarine. It has been run twice a year since 1917, usually starting on 2 July and 14 November each year. It is widely regarded as one of the toughest command courses in the world, with a historical failure rate of 25%.

If at any point during the training a candidate is withdrawn from training they will be nominated for boat transfer and kept occupied until the transfer. Their bag is packed for them and they are notified of the failure when the boat arrives. On departure they are presented with a bottle of whisky. A failure on Perisher means that the unsuccessful candidate is not permitted to return to sea as a member of the Submarine Service (although they are still allowed to wear the dolphin badge). They are, however, permitted to remain in the Royal Navy, moving into the surface fleet.

In more recent years, the United States Navy has sent some of its own submariner officers to undergo the 'Perisher', in order to foster and maintain closer links with the Royal Navy.

In 1995 the Royal Netherlands Navy took over the Perisher course for diesel-electric submarines, since the Royal Navy no longer operates boats of that type. The course is attended by candidate submarine commanders from navies around the world.

Traditions

The Submarine Service has many traditions that are not found in the surface fleet. These include slang unique to submariners (such as referring to the torpedo storage compartment as the Bomb Shop and the diesel engine room as the Donk Shop), a special communications code known as the Dolphin Code and the entitlement of a sailor to wear Dolphins and black cap covers upon entering the service. These are only awarded after completion of training and qualification in ships' systems during the first submarine posting (Part III training).

The Jolly Roger and the Submarine Service