The Imperial Japanese Navy

by Fred T. Jane

SUBMARINES

Japan had no submarines when the war with Russia broke out, but orders for an experimental Holland type boat are said to have been placed.

IX
THE NEW PROGRAMME

The new programme began, in 1904, with the ordering of two 16,400-ton battleships at Elswick and Barrow respectively. They have been named Kashima and Katori.

The following description of the Elswick battleship appeared in the Engineer:—

Her length on the water-line is 455 ft.; her breadth, 78 ft. 2 ins.; her draught, 26 ft. 7½ ins.; and her displacement, in tons, 16,400; and she will carry for her armament four 12-in. guns, twin mounted in barbettes; four 10-in. guns, mounted singly in barbettes; twelve 6-in. guns in the citadel; twelve 12-pounder guns; six Maxim guns; three 3-pounder guns; and five torpedo tubes. The plan shows the disposition of the above-named armament, the arrangement of which has been most carefully considered, so that there is no interference with one another in the firing of the different guns, which, however, are all capable of being trained through large arcs. The 12-in. guns are 26 ft., and the 10-in. 22 ft., above the water-line. The 6-in. guns in the battery are from 13 ft. to 14 ft. above the water-line.

The general disposition of the armour protection is that adopted in the latest and most powerful battleships, the armour amidships being carried from below the water-line right up to the upper deck. Above the level of the upper deck additional protection has been adopted, a 4-in. screen being worked to a height of 7 ft. 6 ins. above the upper deck, and extending between the 10-in. gun positions. The main armour belt, which extends the whole length of the vessel, has a thickness of 9 ins. for more than half its length, tapering to rather less at the extremities. The depth of this belt is from 5 ft. below water to 2 ft. 6 ins. above water. Immediately above this is a belt of 6-in. armour, extending in length from the after 12-in. barbette right forward to the stem. Above this again is the 6-in. citadel armour carried to the height of the upper deck, and enclosing the two 12-in. barbettes. In this citadel are placed ten of the 6-in. guns, divided from one another by screens of 80-lb. armour plating, and firing through ports similar to those adopted in casemates. This citadel arrangement, which is one of the most important features of this and other recent battleships, is really a revival or development of the old box battery arrangement adopted in some of our battleships built in the seventies, such as the Shannon and Alexandra. This arrangement fell into disuse when the great improvement made in ordnance—which for a time kept so far ahead of the improvements in armour—made it necessary to increase the thickness of the armour to make it efficient, and therefore it was only possible to cover a comparatively small area of the vessel’s side. However, the recent improvements in armour have been such that again comparatively thin armour is efficient in keeping out projectiles, which has once more made it possible to protect a greater area of side. In more recent years the same system with protective divisions between the guns in the battery was adopted in the Nile and Trafalgar, but as the 4-in. armour protecting the battery of each of these vessels was not of a quality to keep out even the smaller armour-piercing shell, the system was not repeated until the latest and most improved armour was adopted in such vessels as our King Edward VII. class, and in the much-talked-of Swiftsure and Triumph. The remaining two 6-in. guns fire through similar ports in the 4-in. screen armour on the upper deck amidships. The barbette armour of the 12-in. guns is 9 ins. thick on the upper portions where exposed, and 5 ins. thick where protection is afforded by the citadel armour. The barbette armour of the 10-in. guns has a thickness of 6 ins., the conning-tower armour is 9 ins. thick, and the observer tower 5 ins. thick. In addition to these two armoured positions for commanding officers, three officers’ shelters are to be built of 3-in. armour, one above the conning-tower and one on each side. Besides the armour described above, a steel protective deck runs throughout the entire length of the vessel, the whole of the machinery, magazines, etc., being kept below. This protective deck has a thickness of 2 ins. on the flat portions amidships, and 3 ins. on the sloping sides, which are carried down to meet the bottom of the main armour belt. At the ends where the armour protection is reduced, this deck has a thickness of 2½ ins. all over. Thick protective plating is also worked on the top of the screen armour at the boat deck level.

Special attention has been paid to the arrangement and disposition of the magazines, so that the ammunition can be got to all the guns with the greatest speed and minimum of trouble. There are independent magazines for each pair of 12-in. guns, and for each 10-in. gun, and an ammunition passage is provided running right round the machinery spaces below the protective deck for the supply of ammunition to the various 6-in. and smaller quickfiring guns. The torpedo tubes are situated in watertight chambers—two tubes forward and two aft firing on the broadsides, and one tube firing right astern, also under water. Special means are provided for rapidly clearing water from these submerged torpedo-rooms in case of emergency.

The general particulars of the main propelling machinery and boilers are as follows: There are twenty Niclausse boilers disposed in three separate boiler-rooms. These boilers will have a working pressure of 230 lbs., and a grate surface of 1300 sq. ft., and a heating surface of 43,000 sq. ft. The twin engines will have four cylinders each, of 36 ins., 56 ins., 63 ins., and 63 ins., with a stroke of 48 ins., and the horse-power will be sufficient to give a speed of at least 18½ knots. The coal bunkers are so arranged as to reinforce the protection given by the armour and protective deck to the engines and boilers, whilst their disposition is such as to require very little trimming to get the coal to the furnaces. The bulk of the coal can also be got to the stokeholds without opening any of the doors in the main watertight bulkheads—a point of very great importance when the vessel is in action. In addition to the coal bunkers below the protective deck, reserve bunkers are arranged on the slopes of the protective deck up to the height of the main deck over the length of the machinery spaces amidships, the total capacity being approximately 2000 tons, which is sufficient to give the vessel a very large radius of action.

A very complete outfit is being provided for the vessel, including the following boats: Two 56-ft. vedette torpedo boats of high speed, one 36-ft. steam pinnace, one 40-ft. launch, one 32-ft. pinnace, three 30-ft. cutters, two 30-ft. gigs. For lifting these boats two powerful electrically worked derricks are provided—one on each side of the vessel.

There is also a powerful electrical equipment, both for providing energy for the numerous machines on board, and also for lighting. The latter will include provision for six searchlights and some 1250 incandescent lamps.

The equipment of anchors and cables includes three stockless bower anchors of 120 cwt. each, and other smaller anchors. There are also three main cables of 150 fathoms each of 2⅝ ins. stud chain.

The vessel being of such an immense weight—over 17,000 tons with her full equipment of coal, stores, etc.—special arrangements have been provided for docking her with safety, and, in addition to shoring ribbands for giving special support to the armour in dock, two docking keels are provided on the flat portions of the bottom under the bilges amidships. These keels will rest on separate lines of blocks in the dock, as well as the usual blocks along the middle line of the vessel. Bilge keels are also provided to reduce rolling in a seaway.

The watertight subdivision of the vessel is of a most thorough description; the inner bottom extends over the whole length of the vessel, and is minutely subdivided, and above this the number of transverse and longitudinal watertight bulkheads is too numerous to mention.

An elaborate system of pumping and draining has been worked out, and in addition to the main pumps in the engine-rooms, which can be used in case of emergency for dealing with a large inrush of water, are two 9-in. pumps, two 5½-in., and one 4½-in., besides pumps for fresh and salt water services.

In a vessel of this description the ventilation arrangements are not the least important of the many items which have to be thought out, and every precaution has been taken for efficiently ventilating spaces both above and below the protective deck. In addition to the natural ventilation, artificial means have to be largely adopted, even in the upper portions of the vessel where she is entirely enclosed in with armour and protective plating, and here, as well as below the protective deck, numerous electrical fans, with air trunks, branches, pipes, etc., are being provided for.

Two complete sets of steering engines, independent of one another and in separate watertight compartments, are fitted, with steering positions both forward and aft. Hand gear is also provided, and appliances for changing as quickly as possible from hand to steam gear, and vice versâ. Tiller indicators are fitted in all the steering and conning-tower positions. Helm signals are provided for the purpose of communicating the position of the helm to other vessels in the neighbourhood. Voice-pipes, telegraphs, and telephones are fitted throughout the vessel to communicate between all the important positions. The vessel is also to be supplied with a wireless telegraphy installation. Torpedo net defence is to be fitted around the greater part of the vessel, which, in view of recent experience, appears to be not an unnecessary precaution.

With the exception of the main propelling machinery and boilers, which are being supplied by Messrs. Humphrys, Tennant and Co., the whole of the ship, with armour, armament, fittings, etc., will be supplied by Sir W. G. Armstrong, Whitworth and Co., Limited.

The 12-in. guns will weigh approximately 59 tons each. The length is 46 ft. 9½ ins. (46.7 calibres). The weight of the projectile is 850 lbs. The charge will be cordite, probably of the modified type. The exact weight of the charge is not yet fixed, and neither can the velocity be given, but these guns will be the most powerful 12-in. guns which have yet been constructed. No armour which any ship can carry can hope to cope with their penetrating powers at 3000 yards. The breech-screw is arranged for a parallel motion, which obviates the necessity of having a steep cone at the seating of the obturating pad. It is yet early to speak of the rapidity of fire to be obtained with these guns, but it is anticipated that, in conjunction with the mounting described, the hitherto obtained rate of approximately two rounds per minute from each gun will be exceeded.

The 10-in. guns will weigh approximately 34 tons each. The length is 39 ft. (46.76 calibres). The weight of the projectile is 500 lbs. The charge will be cordite, probably of the modified type. As in the 12-in. guns, the exact weight of the charge has yet to be fixed, but here again this will be the most powerful gun of its calibre in existence. As a gauge of the power of these guns, it may be noticed that their penetrating power is equal to the penetrating power at 3000 yards of any of the 12-in. guns at present afloat in any navy. The breech mechanism will be somewhat similar in design to that of the 12-in., and will embody all the essential advantages of that design. The rapidity of fire of these guns on the Elswick mounting it is anticipated will at least be at the rate of three rounds per minute with a well-drilled gun’s crew.

The 6-in. guns will weigh approximately 8½ tons. The length is 23 ft. 6 ins. approximately (47 calibres). The weight of the projectile is 100 lbs. The charge will be probably M.D. cordite; but here again this is not definitely fixed, but these guns will be the most powerful guns of their description made, having a penetrating power at 3000 yards equal to, if not exceeding, any 6-in. guns hitherto built. The breech mechanism will be of the Elswick modified coned type, actuated by the single motion of the lever, and, as in the other gun, the necessity for the steep-coned obturator is obviated. The exact type of the smaller guns is not yet settled, but they will also follow the general advances in power and efficiency noted in the case of the heavier armaments.