HMS Alliance was one of sixteen 'A' Class submarines commissioned by the Royal Navy, and was built at the Vickers Armstrong yards, Barrow in Furness. Her keel was laid down on 13th March 1945, and she was launched on 28th July the same year. Quieter than her predecessors, and constructed with a completely welded hull, HMS Alliance is 281ft (85m) long with a beam of 22ft (6.5m) and a draft of 17ft (5m). She was capable of 18.5 knots surfaced, reducing to 8 knots when submerged. Her armament when first completed consisted of ten torpedo tubes (four were originally external, but these were removed on a later refit), one 4 inch gun, one 20mm Oerlikon anti-aircraft gun, three .303 machine guns, and 26 mines. Her normal complement was 68, including five officers.
Designed to operate in the Far East, HMS Alliance was built for long distance patrolling and had a range of some 10,000 miles. To facilitate this requirement HMS Alliance had to be bigger than her predecessors, able to accommodate a greater weapons load, carry more on-board supplies, and have better living accommodation for her crew. HMS Alliance was first commissioned on 14th May 1947 and, in common with most submarines, her operational service history still remains largely a mystery. A few moments from her service career that have been documented, include an occasion in October 1947 when HMS Alliance made a thirty day 'snort' cruise to test a device that had been pioneered by the Germans during the latter war years. A 'snorkel' tube basically drew air from the surface allowing the diesel generators to continue running, thus charging the batteries whilst the submarine was submerged. This meant that HMS Alliance could stay just below the surface for much longer periods and was therefore much more difficult to detect.
During the late 1950s HMS Alliance underwent a major refit, resulting in a much more streamlined appearance. This streamlining not only afforded her greater endurance when submerged, but gave her an improved speed (ten knots as opposed to eight) and, more importantly for a submarine, made her much quieter. Her surface displacement after modernisation was 1,385 tons. Throughout her thirty years of service, HMS Alliance did suffer a few unfortunate incidents. On 13th January 1968 she ran aground off the Isle of Wight, and it was three days before she could be floated off. Later in the same year HMS Alliance suffered an onboard fire. In the early 1970s two battery related explosions were recorded, one of which killed an individual and injured fourteen others, and during the same period HMS Alliance was reported as having hit the seabed whilst performing a test dive.
With the emergence of the Oberon and Porpoise class submarines, HMS Alliance's active service days were soon over. By 1973 she was being used solely for harbour training duties, and this continued for several years until she was transferred on permanent loan to the Gosport Submarine Museum. Since 28th February 1978, HMS Alliance has remained the centrepiece of the museum, standing as a memorial to over 4,000 British submariners who lost their lives whilst on active duty.