G3 battlecruiser

The G3 battlecruisers were a class of battlecruiser planned for the Royal Navy after the end of World War I and news of naval expansion programs by the United States and Japan. The four ships of this class would have been larger, faster and more heavily-armed than any existing battleship (although several projected foreign ships would be larger). The "battlecruiser" designation came from their higher speed and lesser firepower and armour relative to the planned N3 class battleship design. The G3s were expected to achieve 32 knots and carry nine 16 inch guns, while the N3s would carry nine 18 inch guns (45.7 cm)) on the same displacement at the expense of a slower speed. While generally referred to as "battlecruisers", the G3s have also been considered "fast battleships". [ [http://www.bobhenneman.info/1921classhistory.htm History of the 1921 Project ] ]

The G3 design was approved by the Board of Admiralty on 12 August 1921. Orders were placed in October but suspended in November with the starting of the Washington Naval Conference which met to limit battleship production. The orders were cancelled with the adoption of the Washington Naval Treaty which limited construction to ships of no more than 35,000 tons displacement.

Background

In 1916 the US had declared its intention to create a Navy "second to none"; Congress had authorized the building of a large number of battleships and battlecruisers. [Anthony Preston, "Battleships"] In the aftermath of the First World War, the Japanese government were also embarking on programme of warship building. Meanwhile, in Great Britain, the expectancy of the First World War had led to the pre-war "Queen Elizabeth" class battleships being followed by the slower and cheaper "Revenge" class. Two "Revenge" class hulls were converted during construction into the two "Renown" class battlecruisers as emergency builds during the war. The only new capital ships laid down in the war were the Admiral class battlecruisers. Their design had been called into question after the Battle of Jutland in 1916. Three of this class were cancelled, leaving only the "Hood" to be completed to an altered design.

The US plan had been delayed by the wartime need to build smaller vessels. Nevertheless, estimates by the Admiralty were that by the early 1920's the UK would be behind in ships. The British did have access to German technology through ships such as the SMS "Baden" which had been saved from the scuttling of the interned German High Seas Fleet in Scapa Flow and the experiences of the war. A committee concluded that any new ship should be able to match the speed of the new US "Lexington" class battlecruiser, expected to make 32 knots.Consequently a series of designs was prepared of ships with displacements ranging from 53,100 to 44,500 tons, the only limitations being the ability to use British dockyards and passage through the Suez canal. These designs were given letters of the alphabet running backwards from K to G. The related battleship designs under consideration at the same time had design letters from L upwards. The numeral 3 came from the disposition of the main armament in triple mount turrets.

Design

The G3s incorporated several novel features for "Dreadnought"-era capital ships, or at least for British designs of this type. Most immediately noticeable was the concentration of the main battery forward of the bridge and engineering spaces, giving the ships a tanker-like appearance. [The two "Nelson" class, built to a similar layout, were nicknamed "Nelsol" and "Rodnol" due to their resemblance to a class of Royal Fleet Auxiliary oilers whose names ended in "-ol".] Since the G3s were to use existing dockyard facilities, this layout allowed designers to keep the length of the ships, as well as the weight of armour, to a minimum. The resulting loss of heavy fire astern was considered justifible since the ships were intended to fight on the broadside. [This arrangement of the main armament was later used in the French Navy's "Dunkerque" and "Richelieu" class battleships. As both French designs had only two turrets these were given as wide a separation as allowed by the other design constraints.] A related feature of the G3 and N3 designs was their tower bridge structure behind the first two gun turrets. This reduced draughts, provided a better and more stable foundation for fire control gear and could be made secure against gas attacks.

Along with keeping armor weight to a minimum was the use of the all or nothing protection scheme. Portions of the ship were either unarmoured or given armouring as thick as possible. Use of this system was inspired by contemporary U.S. Navy battleship designs starting with the "Nevada" class; however, the practice originated from the Victorian-era "central citadel" ironclads designed by Nathaniel Barnaby during his time as the Royal Navy's Director of Naval Construction. The design also incorporated a thoroughly designed and tested [A full-scale mockup of a section of the proposed G3 armouring scheme was built and used for live-fire testing.] underwater protection system.

Housing the main armament in triple turrets was new to the Royal Navy though British companies had been involved in the production of triple gun turret designs for other navies. ["Battleships" Anthony Preston] . The choice of a high muzzle velocity with a relatively lighter shell was taken from the German practice; it ran counter to previous British guns such as the 15 inch L/42 which were lower muzzle velocity weapons firing heavy shells. When tested problems were found, the muzzle velocity was reduced. The BL 16 inch /45 naval gun would deliver a range of 35,000 yards with a 2,000 lb shell.

The G3s carried a secondary armament of 16 six-inch guns in twin turrets instead of casemates—the first time in a British capital ship since the "Lord Nelsons" of 1904. Four turrets were sited around the citadel, four at the stern. In addition an anti-aircraft battery of 4.7 inch guns was included with dedicated fire control equipment. In previous ships the anti-aircraft guns could only be manually-aimed in the rough direction of approaching aircraft, a method which proved ineffective. To this was added lighter guns in the form of four 10-barreled two-pounder mounts. At a practical rate of 50 to 75 rounds per minute per barrel, these were intended to throw up a lot of fire which would disrupt an aerial attack.

Like previous classes—and despite their dubious performance during the First World War—broadside-firing torpedo tubes were planned for these ships. However, the torpedoes intended for use aboard the new ships—and ultimately installed in the "Nelsons"—used oxygen-enriched propulsion. Japanese reports of these weapons prompted the Japanese Navy to develop a similar series of torpedoes, culminating in the famous Long Lance.

Had the G3s been completed to their design specifications, the Royal Navy would have possessed a quartet of warships roughly equivalent, given suitable modernization, to the "Iowa" and "Lion" class battleships designed twenty years later.Fact|date=January 2008. The "Iowas" and planned "Lions" did not use the all-forward armament scheme.

Cancellation

The introduction of the Washington Naval Treaty, an arms limitation treaty intended to curtail an arms race between competing navies in the post-Great War period, led to the suspension of building in November 1921 and outright cancellation in February 1922. Although all four ships were ordered, none were laid down. It has been suggested that the Royal Navy used the class to compel the US and Japanese to sign the treaty. Previous to the Washington Naval Conference, however, the Admiralty showed every sign that these ships would be completed. The G3 had been favoured ahead of the N3 because of the expected slow supply of 18 inch guns for the N3. Only one British company could provide 18-inch guns whereas four could build 16-inch guns readily.

Many of the aspects of their design ultimately were incorporated into the two "Nelson" class battleships, and the latter design is often described as being a cut-down G3. Indeed, the "Nelsons" received the design designation O3, marking them as next in the design line from the N3 class although they used the guns intended for the G3 class (which were already under construction) for economy and to comply with the 16 inch limitation on main armament of the Treaty.

Naming

Officially the G3 class were never given names, however several ideas on possible naming schemes have been advanced. Among these names speculated for the four ships planned were "Invincible", "Indomitable", "Inflexible" and "Indefatigable" from the First World War battlecruisers. [Siegfried Breyer, "Battleships and Battlecruisers 1905-1970" (Doubleday and Company; Garden City, New York, 1973)] Another suggestion is that they were to be another "Admiral" class and carry the names "Nelson", "Rodney", "Anson", and "Howe".

Notes

References

* Siegfried Breyer, "Battleships and Battlecruisers 1905-1970" (Doubleday and Company; Garden City, New York, 1973) (originally published in German as "Schlachtschiffe und Schlachtkreuzer 1905-1970", J.F. Lehmanns, Verlag, Munchen, 1970).

ee also

*Lexington class battle cruiser - a contemporary but less technically-advanced U.S. design also cancelled as a result of the Washington Treaty