The British U-Class submarines were a class of 49 small submarines built just before and during the Second World War. Mushroom cloud from the nuclear explosion over Nagasaki rising 18 km into the air. ...

These small submarines, of around 630 tons, were originally intended as unarmed training vessels to replace the ageing H class, to be used as practice targets in anti-submarine training exercises. The first three boats, HMS Undine, HMS Unity, and HMS Ursula were ordered in 1936, and during construction were modified to accommodate four internal and two external bow tubes. Apart from Undine and Unity, all boats were also equipped with a 3 inch gun, although they lacked a hatch for the gun crew, who had instead to use the main conning tower hatch.

As war loomed, twelve more vessels were ordered, although only four had the external tubes. These were dropped from later vessels because they generated a large bow wave and made depth keeping more difficult at periscope depth.

Equipped with torpedo tubes, they proved to be useful warships in the confined waters of the North Sea and partuclarly in the Mediterranean. A further 41 vessels, forming the second group, were ordered in 1940 and 1941. They were similar to the first group, but were lengthened by 5 feet to provide a more streamlined shape. All but two of the 49 boats built were constructed by Vickers. A modern torpedo, historically called a locomotive torpedo, is a self-propelled projectile that (after being launched above or below the water surface) operates underwater and is designed to detonate on contact or in proximity to a target. ... The North Sea is a sea of the Atlantic Ocean, located between the coasts of Norway and Denmark in the east, the coast of the British Isles in the west, and the German, Dutch, Belgian and French coasts in the south. ... The Mediterranean Sea is an intercontinental sea positioned between Europe to the north, Africa to the south and Asia to the east, covering an approximate area of 2. ...

Most of the boats built served with part of the 2nd Submarine Flotilla based at Malta. 19 were lost during the war; 13 in the Mediterranean and the remainder in the North Sea and Atlantic Ocean. In addition, one vessel, HMS Untamed sank in May 1943 but was salvaged and reconstructed to be recomissioned as HMS Vitality. From 1941, some of the boats were transferred to Soviet, Free French and other allied navies.

The design was developed into the welded V class later in the war.

Most of the submarines were powered by electric motors that could put out about 800 to 1000 horsepower. Electric motors of various sizes. ... The horsepower (hp) is the name of several non-metric units of power. ...

One of the most famous U-class submarines was HMS Upholder, commanded for its entire career by Lieutenant-Commander Malcolm Wanklyn. Wanklyn received a Victoria Cross for attacking a well-defended convoy on 25 May 1941 and sinking an Italian liner, Conte Rosso. In her 16 month operational career in the Mediterranean, before she was sunk in April 1942, Upholder carried out 24 patrols and sank around 119,000 tons of Axis ships – 3 U-boats, one destroyer, 15 transport ships and possibly a cruiser and a destroyer. HMS Upholder (P37) was a U-class submarine of the Royal Navy. ... In the Royal Navy, United States Navy, Royal Australian Navy, Royal New Zealand Navy, Canadian Forces Maritime Command (formerly the Royal Canadian Navy), United States Coast Guard, and many other navies and coast guards, a lieutenant commander (lieutenant-commander or Lt Cdr in the RN and abbreviated LCDR in the... Photo submitted by Simon Manchee Malcolm David Wanklyn (VC, DSO & 2 Bars) was a recipient of the Victoria Cross, the highest and most prestigious award for gallantry in the face of the enemy that can be awarded to British and Commonwealth forces. ... Victoria Cross medal, ribbon, and bar. ... A convoy is a group of vehicles or ships traveling together for mutual support. ... May 25 is the 145th day of the year in the Gregorian calendar (146th in leap years). ... This article is about the year. ... A liner is a big passenger ship where the passengers can sleep onboard. ...

The last surviving U-class boats were scrapped in 1950.

References

• Uboat.net
• Submariners Association