Group 3 S Class: Patrol Submarine
Built under the 1939;1940/41 and 1942/43 emergency war programmes, 54 Group 3 boats were completed between 1942 and 1945. Cammell Laird at Birkenhead produced the majority of the class with just three being completed at Chatham. This class of submarine was an improved design of the Swordfish class.
The early boats had riveted pressure hulls and welded frames but with the exception of two, from 1942, the boats were completely welded construction. This not only increased the diving depth but also gave greater strength during depth charge attacks.
The range was also increased on the later boats by converting some of the ballast tanks to carry fuel.
During the war, these boats served in Home waters, the Mediterranean Sea, the Indian Ocean and although not suited to the area, in the Pacific.
Entering the war late, this class of submarine still accounted for many thousands of tons of shipping and carried out many clandestine operations.
Four S class took part in operation Source, towing X craft to Altenfjord for the attack on Tirpitz. Possibly the most remembered operation being that of Seraph off the Spanish coast in 1943. When, the body of Jack Melville, dressed as a Royal Marine Officer was placed into the sea. The operation to deceive the enemy into believing Allied landings would be in Sardinia rather than Sicily, was made famous by the 1956 film, The Man Who Never Was. HMS/m Scythian played the role of Seraph in the film.
After the war, 14 boats had their gun removed and a Snort Mast fitted.
This group of boat was in service into the 1960's.