In December 1913, after discussing the German submarine programme, the Admiralty decided that they should prepare a design for an overseas patrol boat of about E Class surface displacement, of partial double-hull construction and with single 21-inch torpedo tubes forward and aft and two 18-inch beam tubes. This would be the G Class.
G Class Submarines
1914-1921
In June 1914, five G Class submarines, G1 to G5, were ordered from Chatham Dockyard and one month later G6 and G7 were ordered from Armstrong Whitworth. Vickers engines of the E Class type were fitted in all seven boats, although it was originally intended to fit G6 and G7 with Nuremberg (MAN)
