Читать книгу The British Battleship - Norman Friedman - Страница 13
ОглавлениеBY 1905, it was widely accepted that battleship and armoured cruiser designs were drawing together. For example, three years earlier the Board asked the Royal Naval War College to compare a fast battleship with reduced armour and armament with a more conventional slow battleship in a fleet action. The study was inspired by the advent of the US Navy’s Tennessee class (four 10in guns, 22 knots), which the Royal Navy (but not the US Navy) considered a fast battleship. During the design of the Minotaur class armoured cruisers, the last of their kind in the Royal Navy, a version with a nearly uniform-calibre main battery was sketched.1 It might be considered broadly equivalent to the all-big-gun versions of the Lord Nelson design sketched at about the same time.
It could be argued that the new cruisers were a halfway stage to an inevitable merger of the battleship and armoured cruiser types. Fisher once wrote that it was as impossible to prevent such a merger as to prevent a kitten from growing up into a cat. In 1906 he went further, arguing that the Invincibles were ‘perfectly fit to be in line of battle with the battle fleet and could more correctly be described as battleships which, thanks to their speed, can drive anything afloat off the seas’.2 In effect he solved the problem Lord Selborne had posed with the 2:1 ratio by merging the dreadnought and dreadnought cruiser categories into a single category of dreadnought capital ships. After three battlecruisers were destroyed at Jutland, many claimed that these ships had been misused, that they had never been intended to be part of a battle fleet. They avoided the reality that in 1916 the Royal Navy’s technical experts, such as DNC, concluded that the losses had been due, not to inadequate armour, but to suicidal magazine practices intended to make for faster fire. Battlecruisers had a variety of roles – including fighting other battlecruisers armed with battleship-calibre guns. Any ship capable of standing up to such fire had a perfectly valid place in a battle fleet.
Going back to 1904, Fisher envisaged a small force of extremely fast, powerful armoured cruisers. The initial version of his manifesto Naval Necessities envisaged an all-big-gun armoured cruiser which he called HMS Unapproachable. It would be armed with sixteen 9.2in guns. This presumably reflected a sketch design, now lost, prepared by Fisher’s associate W H Gard, who was then constructor at Portsmouth. Soon after Fisher took office, Watts was asked for two parallel designs for a new armoured cruiser: (1) a Minotaur armed with sixteen 9.2in guns in pairs (one at each end, three mountings on each side); and (2) a 25.5-knot ship (reciprocating engines) armed with eight 12in guns in pairs, armoured like a Minotaur. The two forward turrets were to be side by side, the after ones superfiring.3 Design (1) was ‘very urgent’. Initially the intention seems to have been to redesign the ships already building. Watts wrote that the present armament could be replaced as desired if an increased draught of 6in was accepted and the boiler room bulkheads slightly rearranged. Because 7.5in mountings had already been ordered, an early decision was needed if any change was to be made. A Legend showed alternatives with sixteen and fourteen 9.2in guns (two guns in single mountings corresponding to the amidships single 7.5in mountings in the Duke of Edinburgh). Nothing came of this proposal.
HMS Invincible as modified shortly after completion, with the foremast searchlight removed in favour of lights on the bridge wings. The guns atop ‘A’ and ‘X’ turrets have been given portable screens to protect their crews from the glare of these lights; note that there are no such screens for the wing guns.
Indomitable as built. The extensive boat stowage raises a question: boats were stowed around the after conning tower, leaving it almost no view unless they were landed. However, ships retained their boats in battle. The plan view shows a rectangular area just forward of the after funnel and slightly to port of centreline on the forecastle deck marked ‘hangar’. It is otherwise empty of fittings, hatches, ventilators, etc. Although it is on a plan dated 1908, it may have been added somewhat later (but the plan does not show the major changes made during the First World War). Some later ships had blast screens to protect their boats, but the Invincibles and the early dreadnought battleships did not. Note that much of the high superstructure was not roofed; they were labelled as blast screens on plans (many plans and models inaccurately show decks over these structures). This ship and other British battlecruisers had noticeable tumblehome to their hulls (the dreadnoughts did not). Photographs of these ships taken before the First World War show that from time to time their torpedo net booms (and netting) were apparently removed, only to be restored later. As the attachment points of the booms were very close to the water, the entire boom set could be hauled up and lashed atop the netting. Note the five torpedo tubes, including a stern tube. Torpedoes were stowed both inside the torpedo room and in a compartment above it. The circular cage structure on the port side of the after funnel surrounded the end of the vertical wireless antenna (which is not shown). This was a standard fitting on Royal Navy warships up to the end of the Second World War. It protected shipboard personnel from touching the antenna as it went through the deck to the wireless office below. (A D Baker III)
In the late autumn of 1904 work on the new battleship apparently had a higher priority. Fisher ordered a series of armoured cruiser designs armed with eight 12in guns and 4in anti-torpedo (boat) guns. The first two (Designs A and B) were described in a Legend given to DNC on 4 January 1905. They were different arrangements to meet alternative (2) of the previous year’s memo. Design A was the sketch requested the previous November. It economised on armour weight by enclosing the two pairs of turrets at either end of the ship in a single redoubt rather than using separate barbettes. On this basis Design A was expected to displace 17,000 tons.
In January 1905 Fisher told his Committee on Designs that he wanted ships armed with 12in guns (and nothing smaller except anti-torpedo guns), armoured like the most recent armoured cruisers (Minotaur class) and capable of 25 knots: ‘the Armoured Cruiser is the embodiment of armed speed’. The argument for the 12in gun was, he said, the same as that for the battleship, ‘but the overriding qualification is speed’. Since some new foreign armoured cruisers were credited with 24 knots, the new British ship must be capable of at least 25 knots (preferably 25.5). In order to fit into existing docks, she would have to sacrifice some guns and armour, compared to the battleship. The fast 12in armoured cruiser should render all existing cruisers obsolete, as she could overtake and annihilate anything at sea apart from the new all-big-gun battleship
The new armoured cruiser would also have a battle fleet function: to overtake and keep touch with a fleeing enemy fleet, ‘and possibly bring it to bay by the wounding which her 12in guns are capable of at a distance of 7 miles or more . . . The Japanese contention is that the Armoured Cruiser will be able if needs be to lie in the Line of Battle, because of her uniform armament of 12in guns, which is the armament of the Battleship. Indeed, these Armoured Cruisers are Battleships in disguise! for their armour, though thinner than that of the Battleship, practically offers infinitely more resistance than theory allows’. Fisher argued that such ships would almost never be hit at right angles. If hit at an angle of 30°, the belt would have considerably more resistance, more like battleship armour. ‘Their [Japanese] new Battleship is a glorified Armoured Cruiser, as they say they cannot at present afford to have both, nor can they afford to go to our displacements’.
A rigging plan of Indomitable, as built, shows rigging for her torpedo net booms, but the all-important wireless antenna is not depicted. Wireless range depended on the height of the antenna and also on the length of the horizontal element it joined; the Royal Navy eventually used cage-like horizontals to increase effective length. The battlecruisers were given especially tall topmasts specifically to increase the range at which they could receive signals from the Admiralty. The antenna terminated in a Faraday cage (vertical conducting elements) on deck before passing down to a radio room. (© National Maritime Museum)
HMS Inflexible as completed, with all her funnels of equal height and with a searchlight at her foretop.
The battlecruiser was an extrapolation of the earlier armoured cruiser. The question of why it was conceived would not even be asked had three battlecruisers not been destroyed at Jutland – not because of poor protection but because of suicidal magazine practices. The great question before 1914 was whether battlecruisers should be organised in squadrons, like armoured cruisers, or dispersed to back up the cruisers intended to maintain a light cover of the German coast. In 1914 the Royal Navy planned to break up its battlecruiser squadron so as to form combinations of battlecruisers and light cruisers – which would have been snapped up by the concentrated German battlecruiser force. Photographed before the war, the First Cruiser Squadron illustrates the evolution of the British battlecruiser from large armoured cruisers (at left) to 12in cruisers (middle) to the ‘Splendid Cats’ armed with 13.5in guns (at right), the line being led by HMS Lion. The formation of the squadron strongly suggests that the Royal Navy saw the battlecruiser and the big armoured cruiser as closely related, although the armoured cruisers were substantially slower. It might be added that the major navies all continued to build battlecruisers after Jutland, albeit with better protection. That is not obvious nearly a century later only because most of the ships involved were never completed, due either to the end of the First World War (the Germans and some of the British) or to the Washington Naval Conference (US Navy and Imperial Japanese Navy). Inter-war US wargaming showed just how great a disadvantage it was not to have such ships and the Naval War College successfully pressed for fast battleships (battlecruisers) in 1933. Similarly, the British post-treaty battleships (King George V class) were initially described as battlecruisers. (Dr David Stevens, RAN Seapower Centre)
HMS Indomitable as completed for trials, without 4in guns atop ‘A’ and ‘X’ turrets, but with water tanks abaft the break of the forecastle, intended to measure the loss of feed water during the trials.
Inflexible shows the two main pre-1914 modifications to the class: the raised forefunnel and the horizontal cylindrical range indicator on the foretop (the one on the maintop is less visible; initially Invincible had only the forward one). Range indicators were removed from all three ships in 1912–13. The single white band on her forefunnel identified her (Invincible had white bands on each funnel, Inflexible one white band on her third funnel). The objects at the rear of ‘A’ turret appear to be foundations for a glare screen, to be erected as desired. Without the usual canvas ‘dodger’ in place, the compass platform shows its two main fittings, the standard compass and a revolving chart table (so that it could be oriented as desired to match the ship’s heading). The vertical object visible abaft the forefunnel is a mechanical semaphore, a standard Royal Navy signalling device of this era.
Indomitable shows why the forefunnel was raised. The range indicator on her foretop is barely visible with even moderate smoke from that funnel. She had her forefunnel raised in 1910, her sister Inflexible following the next year. (Photograph by Cribb via US Navy)
Working up to full speed, probably at the battle of the Falklands (December 1914), Invincible had had at least the 4in guns on ‘A’ and ‘Y’ turrets remounted in her superstructure (note the higher guns forward); it is not clear from this photograph whether the guns on ‘P’ and ‘Q’ turrets were also removed. The other guns in the forward superstructure had had their embrasures turned into protected casemates. A main-battery director has been mounted on the foremast under the foretop and the foretop extended forward, probably to accommodate a 9ft rangefinder (note that the maintop was unaltered). The roof of ‘A’ turret seems to show the bump of a rangefinder. Note the anti-rangefinding spiral on the foremast. Her forefunnel was raised on the way home from the Falklands (February 1915). The after 4in guns were not given shields until after Jutland.
Design A was given to the Committee on Designs after its first meeting. Like some of the battleship designs, it was described as the embodiment of Admiral Wilson’s tactical ideas. He emphasised the need for end-on fire in a chase, hence the two turrets placed side by side. Six of her eight guns could fire on the broadside, should she lie in the line of battle. By this time the Committee was familiar with the blast issue, which seemed to rule out the superfiring turret aft. It also pointed to the considerable target area presented by the two after turrets and to the insufficient command of the aftermost turret. The naval members of the committee objected to the side-by-side arrangement of the forward turrets due both to blast and to loss of seagoing qualities (due to the weight concentrated forward). They wanted an alternative arrangement which would still meet the requirement of ahead fire.
In the absence of complete data on blast, DNC was asked for two more designs, B and C, which adhered to Admiral Wilson’s ideas but reduced blast by eliminating superfiring aft. Design B (17,200 tons) had the two after turrets side by side rather than superfiring. An alternative Design C (15,600 tons) had only one twin turret aft, displacement being reduced to 15,600 tons. Each version showed 41,000 IHP and four single funnels. The thirteen anti-torpedo guns were all in superstructure embrasures. When the sub-committee of naval officers and Admiralty officials considered blast effects, they rejected the side-by-side turrets of B and C. Neither was therefore offered to the full Committee. No practical design could offer the desired combination of end-on and broadside fire. Given the fineness of a cruiser hull (for speed), it would be impossible to group guns near her ends. It also turned out that every further alternative offering good end-on fire also gave good broadside fire, a quality the Sub-Committee liked because ‘it makes the Armoured Cruiser all the more qualified to lie in the line of battle if required to do so’ (italics in the original).
To avoid blast, turrets had to be as far apart as possible. The Sub-Committee asked that two turrets be placed more or less side-by-side amidships. Designs D and E were presented to the Sub-Committee on 5 January 1905. In D, the midships turrets were side by side, so that the broadside was six guns and end-on fire was four (each waist turret could not fire exactly end-on, as sighting positions would become untenable). This arrangement gave the cruiser the same end-on fire as the new battleship. In Design E, the two waist turrets were splayed out fore and aft. DNC decided to move the amidships guns in E towards the centreline, keeping them as close together as possible fore and aft. Presumably that was to move their magazines as far as possible from the skin of the ship. There would be four shafts and possibly turbines (another sheet also dated 7 January indicated that a reciprocating design would have two shafts, a turbine ship four). According to the Committee report, one very great advantage of the new designs compared to those proposed by Wilson was considerable weight saving – 1000 tons – and corresponding reduction in length.
Indomitable is shown as modified by the end of the war. Her bridge structure is little changed, except for splinter mattresses around the various levels and the openwork between the charthouse and the compass platform has been filled in. Above the bridge is a rangefinder. Another rangefinder, probably with an associated director, has been mounted atop the foretop. The box abaft it is a torpedo lookout position. The most dramatic change since before the war is the movement of all 4in guns into the superstructure, in casemates. Atop ‘A’ turret is an anti-aircraft gun. Also evident are the searchlight towers built (after Jutland) around the third funnel, the aircraft take-off position atop ‘P’ turret and a large Carley float just forward of the second funnel. The deflection markings on ‘A’ turret were intended to show other ships in company where the target was; a range dial is just visible on the fore side of the foretop. A reported attempt by the Admiralty to sell this ship and her sister Inflexible to Chile in 1919 failed. Both ships were placed on the sale list before the Washington Conference opened.
At the end of the war Inflexible could be distinguished from Indomitable by the separate platform built above her bridge, around the legs of her tripod foremast. Above it to the left is a forebridge rangefinder. The bulge visible at the after end of ‘A’ turret was a 9ft rangefinder. The vertical object which seems to protrude from the platform abeam her forefunnel was a semaphore, with a searchlight in front of it. One of two 4in high-angle guns is visible on a platform abaft the second funnel. The range dial on the foretop is visible, but the deflection markings on ‘A’ turret are nearly washed out. The frames of an aircraft take-off platform are visible on the guns of ‘Q’ turret.
Inflexible at sea, 1918. Her foretopmast has been taken down. The 4in high-angle gun is between the two forward funnels, the 3in high-angle gun on the port side of her second funnel. ‘Q’ turret shows a flying-off platform with an aircraft; ‘P’ turret on the opposite side of the ship was similarly equipped. The after funnel shows post-Jutland searchlight towers.
Designs D and E were submitted to the Committee on Designs on 12 January. Watts’ cruiser designer Whiting asked what space would be needed in Design E to allow one turret to train on the opposite broadside. The report of the Committee on Designs claimed that each turret was capable of firing over the other broadside within an arc of about 30°, but that did not take blast interference into account. The winning argument seems to have been that if one of the waist turrets was put out of action the other could still fire on that side. On 12 January 1905 the Committee on Designs voted in favour of Arrangement E and the next day the Admiralty members agreed to recommend Design E (with turbines). Claimed weight savings were an important reason for adopting turbines.4 An alternative Design F was dropped.5
On 25 January 1905 the full Committee on Designs decided that the new armoured cruiser should be designed for 25 knots when carrying 1000 tons of coal. A model of the cruiser, by then named Invincible, was ready for inspection on 6 February. It showed two tripod masts, a heavy mast aft to handle the four heavy boats and a light one forward to handle the light boats. Each mast would carry a fire-control position. At this point the anti-torpedo (boat) battery was twenty 12pdrs: seven each on the forward and aft flying decks (the upper decks of the superstructure, carrying the boats), two on the forecastle deck and one on each turret).
As in the Dreadnought design, it was decided to reduce some armour to provide 2½in underwater protection to the magazines. The width of the 6in amidships belt was reduced by 6in and 50ft of forward 4in armour reduced to 3in; 12in turret armour was reduced from 8in to 7in on sides and rear; barbettes were reduced from 8in to 7in; and the heights of the centres of the forward 12in guns above water were reduced from 34ft to 32ft. As of March 1905 the ship was expected to displace 16,750 tons and the anti-torpedo battery was eighteen 12pdrs. Expected speed was 25 knots (rather than the 25.5 knots originally desired). The Board formally approved the proposed outline design on 20 March 1905.
Like their pre-dreadnought predecessors, Dreadnought and Invincible used coal both for propulsion and for a degree of protection against both shellfire and underwater explosions. By the time they were built, the Royal Navy was burning oil as well as coal in its boilers, so both stowed oil in their double bottoms. The Royal Navy rejected above-water oil stowage for fear of fire; it took many years to realise that oil was a useful buffer against torpedo hits. (John Roberts)
The main change after approval was in the anti-torpedo battery. Torpedo defence guns were grouped for control, each group provided with its own searchlight (DNO wanted twelve groups, each covering a 30° arc, each able to reinforce the next group on either side). Guns on centreline turrets could not be used at night due to the blast of neighbouring superstructure guns and the glare of searchlights, but they might be retained for use during a day action. They were not included in DNO’s list, but he did place two guns each atop ‘B’ and ‘C’ turrets and two guns on the forecastle as in Dreadnought. The searchlights were crucial, because it was assumed that most torpedo attacks would be made at night, before or after a battle. However, a battlecruiser also had to be able to deal with day attacks, because she might operate alone near an enemy base. Ideally groups should overlap for mutual support. Reviewing the design in May 1906, DNO objected to its weak end-on fire. Only one searchlight would bear right aft.
This discussion led to rearrangement of the anti-torpedo guns, two atop each turret. This arrangement offered each 12in gun a practice gun without any need for sub-calibre guns. It was also claimed that turret-top guns were less liable to damage during a day action, as only a direct hit could affect them. By this time trials against the old destroyer Skate had shown that the 12pdr might not be enough to stop an oncoming torpedo boat before it could launch its weapons. DNO’s preferred weapon was a high-velocity 4in/50 firing a shell more than twice as heavy as that of the 12pdr; he proposed sixteen of them, each group associated with a 36in electrically-controlled searchlight. In 1906 this weapon was still in the design stage. Because the armoured cruiser project was so urgent, the ships were armed with the existing low-velocity 4in gun (2300ft/sec vs 2600ft/sec for the 12pdr). The paired turret-top arrangement was retained. HMS Excellent (the gunnery school, hence test facility) commented that the turret-top guns would be very well placed to repel torpedo craft by day and that training the turret would give them a very wide arc.6 Blast screens could protect the 4in guns from 12in gun blast. The problem of glare from the searchlights was more complex.7 Substitution of 4in for 12pdrs added 65 tons, which was taken from the Board Margin. Inflexible, the ship with electrical rather than hydraulic mountings, had to carry another 180 tons. All the ships had to add 80 tons to balance their 12in mountings.
The electric gun mountings in Inflexible were unsuccessful and by February 1912 plans called for converting them to hydraulics, as in the other ships of the class. That took six months. At the same time, First Sea Lord recommended that each turret be fitted with a rangefinder, so that it could be self-contained.8 Initial plans were to provide only ‘A’ turret with a rangefinder.
