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Naval Warfare

HMS Swiftsure (S126)

Nuclear-Powered Attack Submarine [ 1973 ]

HMS Swiftsure S126 had her career cut short in 1992 by structural issues - outlasted in service with the Royal Navy by her sisters.

Authored By: Staff Writer | Last Edited: 12/11/2017 | Content ©www.MilitaryFactory.com | The following text is exclusive to this site.

HMS Swiftsure (S126) served the British Royal Navy (RN) during the latter portion of the Cold War period (1947-1991). It was a nuclear-powered attack boat and lead ship of the Swiftsure-class which numbered six. All have since been decommissioned and retired from service. Vickers Shipbuilding and Engineering was responsible for her construction which began on June 6th, 1969 and ended when the vessel was launched on September 7th, 1971. The boat was formally commissioned on April 17th, 1973 and led an operational service life into 1992.

The Swiftsure-class were developed with revised hulls compared to the earlier Churchill, Dreadnought and Valiant classes, affording the new boats increased accessible depths while maintaining speed and control. Unlike these previous offerings, the Swiftsure-class also made use of a shrouded pump-jet propeller unit offering better efficiency and quieter running.

HMS Swiftsure was built to a 4,850 ton standard (surfaced, 5,400 tons dived) and had an overall length of 272 feet with a beam measuring 32.1 feet and a draught down to 27.10 feet. The nuclear powerpack offered essentially unlimited range with surfaced speeds reaching 20 knots and submerged speeds peaking at 28 knots. Aboard was a crew of 116 personnel arranged in shifts. Armament was 5 x 21" (533mm) torpedo tubes cleared to fire the "Spearfish" torpedo family.©MilitaryFactory.com
Once in service, HMS Swiftsure proved her value as a quiet, effective submarine. Her systems allowed her to carefully spy on enemy actions and in this role she excelled. Her armament was never used in anger and she was part of the 1977 operation to acquire the acoustic signature of Kiev, the Soviet Navy's premiere aircraft carrier of the time (which she successfully accomplished. She then entered a period of refitting in April 1980 (delayed since January of 1979) and was not made ready until 1983. From there, a second scheduled refit was intended for 1992 but it was decided to have the boat decommissioned instead - possibly due to cracks in the reactor unit or, more popularly cited, damage to the hull encountered during prior diving trials.

In either case, the ocean-going career of HMS Swiftsure was certainly cut short. The rest of the class managed sailing careers into the 2000s with HMS Sceptre, the forth boat of the class, becoming the last to see retirement in December of 2010.

The Trafalgar-class succeeded the Swiftsure-class in the same undersea role for the RN.©MilitaryFactory.com
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Service Year

United Kingdom national flag graphic
United Kingdom



HMS Swiftsure (S126); HMS Sovereign (S108); HMS Superb (S109); HMS Sceptre (104); HMS Spartan (105); HMS Splendid (S106)

Untied Kingdom (retired)
(OPERATORS list includes past, present, and future operators when applicable)
Submerged Attack
Traveling under the surface to search, track, and / or engage or reconnoiter areas.
Maritime Patrol
Active patroling of vital waterways and maritime areas; can also serve as local deterrence against airborne and seaborne threats.
Fleet Support
Serving in support (either firepower or material) of the main surface fleet in Blue Water environments.

272.0 ft
82.91 m
32.0 ft
9.75 m
28.0 ft
8.53 m

Installed Power: Nuclear-reactor pack fitted.
Surface Speed
20.0 kts
(23.0 mph)
Submerged Speed
28.0 kts
(32.2 mph)
Essentially Unlimited

kts = knots | mph = miles-per-hour | nm = nautical miles | mi = miles | km = kilometers

1 kts = 1.15 mph | 1 nm = 1.15 mi | 1 nm = 1.85 km
5 x 12" (533mm) torpedo tubes (bow-facing); Spearfish torpedo series used.

Supported Types

Graphical image of an aircraft aerial torpedo

(Not all weapon types may be represented in the showcase above)

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