DAMAGE DONE BY WHITEHEAD TORPEDOES.
On February 8 there were 23 Whitehead torpedoes fired, of which only three made hits.
Cesarevitch (Feb. 8).—Outer plating and frames ruptured over a surface about 9 m. by 3 m. by a torpedo explosion; the armored deck deformed for a length of six frame spaces. The armor belt was pushed inward, and the frames behind it greatly deformed over a length of four frame spaces; the rear bulkhead deformed. Four compartments invaded by water. The adjoining bulkheads stood fast, and the damage was wholly local. The ship heeled 17° and it took over an hour to right her.
During the night of August 10, the Cesarevitch was attacked by nine torpedoes, none of which hit; their trajectories could be clearly seen on account of their luminous tracks on the phosphorescent sea.
The remainder of the Russian squadron, re-entering Port Arthur, was attacked by a squadron of 40 torpedo boats, the attacks following one after the other all night. The Poltava alone was struck, and had to be towed in, with her propelling machinery damaged, her rudder broken, and making water fast.
The Diana was attacked by torpedoes nine times without result.
On June 24, in the harbor of Port Arthur, the Japanese torpedo boats attacked eight times without making a single hit.
1 Extract from "Les Avaries de Combat pendant la guerre Russo-Japonaise," by M. C. Ferrand, Ingenieur en chef du Genie maritime, published in the Bulletin de L'Association Technique Maritime, No. 17, Session de 1906.
On July i the cruiser division from Vladivostock was attacked by a small squadron, the night being dear and the attack under good conditions, but not a torpedo reached its mark.
Gromoboi.—The torpedoes had been left on board in the tubes, fully charged. Without doubt they were partially exploded by the impact of fragments, for their war heads dis- appeared and the spoons were found ruptured. But the ship was not injured.
Kniaz-Souvarof.—Already much damaged, she was struck by two torpedoes and sunk.
Sissoi-Veliki.—Struck by two torpedoes during the night; did not sink at once; but either sunk or was allowed to sink the next day when a Japanese division approached.
Admiral-Nakhimof, Vladimir-Ilionomakh.—Wrecked during the night by torpedoes; did not sink till morning.
Navarin.—Struck by two torpedoes on each side, and sunk immediately.
Sebastopol.—This ship was placed, at the end of the siege of Port Arthur, in the outer harbor, to escape bombardment from the inner harbor. She had only a nucleus crew, 300 men instead of 750, and her light artillery had been disembarked; there remained on her only the 6-inch guns. She was protected by Bullivant nets at her middle length, and by a boom defence to seaward. Sixty torpedoes according to some accounts, 180 according to others, were fired at her during five nights. A single one touched her, in the after part. The others ran head on in to the net, whence they were detached and sunk by men sent in a boat. One of them struck the net near its forward end and stuck there with its screw revolving; this lifted the net, and allowed a second torpedo, fired immediately afterwards, to get by. The latter exploded against the Sebastopol's bow, making her sink deep in the water forward; she remained afloat, however, and was sunk two weeks later by the Russians, when they capitulated.
Transport Sado-Maru.—Torpedoed by the Rurik. A first torpedo struck abreast the machinery space, making a hole 4.87 m. by 5. 18 m. Everything in the compartment—pumps, condenser, shafting—was thrown violently out of place. The bulkhead separating the machinery from the boilers was torn apart and one boiler was displaced 10 cm. to 12 cm. The second torpedo exploded in the coal bunker forward of the starboard boiler room, making a breach 2.10 m. by 3.90 m. The explosion smashed the bunker bulkhead and displaced the boiler. Despite these damages, the ship did not sink, and the Japanese were able to get her into dock.
From all these facts it clearly follows that the Japanese torpedo boats were a failure. They succeeded, not without difficulty, in giving the coup de grace to ships already out of action, having for their defence neither searchlights nor light artillery. They were able to approach the Russians near enough, in some cases, "to get in the dead angle of the guns and consequently to be completely sheltered." Doubtless at Tsoushima the sea was rough and unfavorable for torpedo fire, but on August to the sea was smooth.
It would be unwise to deduce from this lack of effectiveness the abandonment of the torpedo boat as a weapon of defence and offence. According to such accounts as we have, the Japanese torpedo boats attacked like a swarm of bees, without order or method, and fired from much too great a distance. Would it be the same with better trained squadrons, and better prepared ones? This may be questioned.
As for the Whitehead torpedo itself, it seems that the Russo-Japanese war definitely classes it as a weapon, very dangerous without doubt, but incapable by itself alone to give the decisive blow to a ship. It causes important damage, often very serious, and obliging the ship to return to port, but more this it can rarely be expected to accomplish.
Moreover it is presumable that by certain measures it would be possible to reduce its effects to such a point that being torpedoed will mean no more than the flooding of one or two compartments, and will not put a ship out of action. The damage it does is much less than that due to a mine of the same weight, doubtless because the rebound causes the explosion to take place at some distance; it is well known how much the effect of an explosion is reduced by the least interposition of a layer of water.
Other lessons are worth remembering: The evening after Tsoushima, if the torpedo and the torpedo boat had such an easy time of it, and if they succeeded in destroying ships but little damaged, it was because the Japanese rapid fire guns had destroyed the latter's searchlights and light artillery. Too much attention cannot be given to this fact, evident as it is, and not needing the illustration of a battle to make it known. The destruction of her light artillery will make a battleship in broad daylight easy prey for the torpedo boat. Is it so difficult to protect the light artillery, and cannot we, instead of installing it in the most exposed parts of a ship, shelter it behind armor?
The 3-inch gun battery of the Russian battleships of the Borodino type was, as a matter of fact, protected by 3-inch armor; was this very thin armor demolished by the Japanese fire? It is very probable; the guns had very large ports; more over fires may have destroyed part of them. We must not be surprised if, under such conditions, the torpedo boat attacks on the Souvar of were successful. The rule of protecting guns by armor of thickness equal to their caliber, which appears to have been applied to the Borodino class, is not defensible in this case; a battleship will never be attacked by 3-inch guns. Guns intended as a defence against torpedo boats then, should be so protected that they can survive a cannonade of several hours; armor of 6-inch thickness is necessary to this end; the method of keeping the light guns under the shelter of the protective deck, and mounting them as best may be when torpedo boat attacks are to be feared, seems inadmissible; in a sudden night attack one will have other things to attend to, in the midst of destruction, besides rapidly getting guns into place. At most a method of this kind might be applied to searchlights.
The incident on the Gromoboi, where the torpedo war heads either burned or exploded without doing much damage, is note-worthy; it shows once more that an explosion in the open has little effect. It would not be safe, however, to conclude from this that we can safely install torpedo batteries above water; the air flask is a greater danger than the explosive charge. The air flasks, however, were completely protected by the torpedo tubes from the very small fragments into which the Japanese shell burst.
DAMAGE DONE BY MINES. Let us now consider the effects of mines.
Gromoboi.—This ship, out from Vladivostock for steam trials, struck a mine moored in 70 m. of water. The charge was 60 kilos of melinite, judging from a similar mine found at the same time on the surface. The impact was abreast the forward boiler room, probably on the bilge keel. The resulting hole extended over seven or eight frame spaces. Outer plating and double bottom demolished; coal bunker bulkhead deformed and admit- ting water through rents; but the bunkers were full of coal and the water entered at a rate not exceeding 200 tons per hour, so that the pumps were able to keep it down.
Bayan.—This ship struck a mine with her bilge keel, to which circumstance her escape from injury may be attributed. In leaving Port Arthur on August Do she struck a mine with her stern, receiving such serious injury as to have to return to port.
Sebastopol.—Having left port on June 23 to chase some Japanese cruisers, she was returning when she struck a Japanese mine, which, bursting on her starboard side, made a breach abreast her mizzen mast and 2.15 m. below the water line, from 2.5 to 3.0 m. in width and 10 to 12m. long, having a total surface of about 37 sq.m. Her frames were twisted and destroyed and the plating projected inboard, but the ship did not sink.
The damage was entirely repaired, the frames and plating being renewed. On September 20, in a sortie, the Sebastopol again struck a mine which damaged her in the same place; this one made a breach of 65 sq.m.
Petropavlosk.—This ship was probably struck by three mines secured by a crows foot to a single mooring cable, so that in striking one of them the other two were also brought into contact with the hull. This arrangement explains the double explosion that was heard. Moreover similar mines were found by dragging in the neighborhood of Port Arthur. It is probable that the mine explosions caused some of the magazines to explode. Another explanation, very unlikely, is that there were mines stowed in her double bottom. The ship was blown up, enveloped in flames, and sunk in a few minutes.
Yashinia.—Two tremendous explosions took place on the starboard side against the hull; the ship heeled 100. The means of keeping down the water were insufficient, and the ship heeled further. Filling compartments on the opposite side only increased the draft without bringing her to an even keel. When the inclination reached 400, there was only just time to get the crew out before she capsized and almost immediately disappeared. In Japan the loss of the Yashima is attributed to the impossibility of closing the doors in the watertight bulkheads, owing to their being jammed by coal. It is also said that the ship would have been, saved if she had not had longitudinal bulkheads.
Chiyoda.—A mine made an opening extending over seven frames; 20 sq. m. of the outer plating was driven in. The opening, at its greatest width, extended from the lower edge of the armor belt to the keel plating, which was itself not deformed. The explosion took place in the third compartment, between bulkheads 2 and 3, and in which is the provision room. It is the largest compartment in the ship. All the surrounding parts were destroyed or greatly damaged. The forward transverse bulkhead was uninjured, the after one slightly displaced; the water entered the coal bunker, but was stopped by bulkhead No. 4. Of three hatch ways, two were closed, but one of them was not watertight. The water entered the armored deck and it was necessary to close the hatch by any means available. Bulkheads 2 and 4, which were a little weakened, were supported by stanchions. The starboard magazine was broken into and filled with water, as well as two other magazines (all in compartment 3). The projectiles were thrown about, but none were broken or burst. The shell room was three meters from the breach in the side. Seven men who were in this room were all killed, their bones being smashed. The gases of explosion entered the deck above by the ammunition passages and asphyxiated 24 men, mostly of the gun crews, so that they were unconscious for six hours. The smell of the gas was apparent even on the upper bridge. The mine charge was doubtless 60 kilos.
A torpedo boat destroyer of the Schichau type struck a mine a breast the officers' quarters. On account of the fine form of the hull, the uprush divided, part going on each side; the decks were pushed within less than a meter of one another, but the plating was not ruptured, and the boat did not sink.
It is worth while to give much thought to the question of automatic mines. Doubtless they are far from new weapons, but never before has their power been manifested to so high a degree. To them is due the loss of more than 60,000 tons of warships.
On the Japanese side, the Hatsuse, Yashinuz, Hei-yen, Sai-yen, Takusago, two gunboats, two torpedo boat destroyers, and two torpedo boats, or about 40,000 tons, sunk. The Akachi and Chiyoda seriously damaged. The Asahi slightly damaged.
On the Russian side, the Petropavlosk, Yenissei, Boyarine, two gunboats, and a torpedo boat destroyer, say 22,000 tons, sunk. The Cesarevitch, Pobieda, Sebastopol, Gromoboi, and Bayan seriously damaged.
Considering that the history of maritime wars teaches that their operations usually take place near the coast, and in places where the water is not deep, we ought to expect, in coming European wars, to see the use of automatic mines developed; doubtless not only naval tactics, but also naval strategy, will have to take account of this novel weapon, and surprises are in store for us. In view of the mediocre efficiency of the Whitehead torpedo, it may even be questioned whether the true role of the torpedo boat, and above all, of the submarine, will not be to strew in the path of an enemy mines similar to those which destroyed the Petropavlosk.
However this may be,the engineer ought henceforth to bend all his energies towards finding a means of protecting ships of war from these terrible weapons.
Three conclusions appear to result from a consideration of all the known explosions:
(1) When the surface exposed to the explosion and the resulting outrush of gas and water is a rounded one, the results are reduced. 2
(2) The difference between the effects produced by the White- head torpedo, exploding after a rebound, and the automatic mine, exploding in contact, shows how much the importance of the explosion is reduced by a slight interval between the charge and object attacked.
(3) By providing an upward escape (vent) for the gases, the effects of the explosion are diverted. This fact is clearly seen by examining the Cesarevitch after her torpedoing on February 8.
It has been proposed, in order to make torpedoes explode at a distance from the hull, to increase the number of bilge keels, or even to place at a certain distance from the hull iron guards, forming a sort of cage with very large meshes. It has also been proposed to armor the inner skin of the double hull with plating
2 The Chatham, loaded with 80 tons of explosives, and sunk in the Suez Canal, was blown up to clear the channel. Two conical buoys, placed by the side of the ship, were not injured by the explosion of the 80,000 kilos of dynamite.
about 50 mm. thick; this, it is said, will be the method adopted by the Japanese Admiralty.
We ask ourselves if a more efficient means of defense than those just mentioned would not result from enveloping the actual hull of a ship by a second, light hull, 5 or 6 mm. thick, about one meter from the inner hull, and extending one or two meters above the water line. This outer hull would be secured to the inner hull by frames, some of which would be watertight, every 10 meters say; this outer hull would have no longitudinals nor any longitudinal bulkheads at its lower part. At the waterline, two longitudinals and transverse compartments would be arranged to diminish the entry of water as a result of gun-fire. In case of being torpedoed, the gases of explosion would escape through the upper part of this hull; water would enter the whole of the corresponding compartment, but the ship would remain upright and would be but slightly increased in draft. Doubtless this arrangement would increase the midship section and so diminish the speed, but there would be savings elsewhere,—part of the double bottom could be dispensed with. The forms necessary to diminish resistance would only be given to the outer hull; the inner hull would be shaped like a series of caissons with walls of simple outline, the armor plates could be parallelopipedons, not curved at great expense to fit the hull.*
We must frankly attack the problem of defence against torpedoes. If it has been, if not neglected, at least considered of secondary importance thus far, this is because the defence against torpedoes was thought to be sufficient and because the known effects of the Whitehead torpedo were such,—and the experience of war has shown the justice of this belief,—that they could be counted on not to do serious damage. The appearance on the scene of the submarine will increase, there is no doubt, the risks of being struck by a Whitehead; moreover, the automatic mine has shown itself to be a terrible engine of destruction, such as in the beginning the automobile torpedo was thought to be. It would be unpardonable, in new ships, to devote 1000 to 1500 tons to the end of giving them a speed useless in actual battle and to economize upon the weight devoted to protection against torpedoes.
* This plan seems to be quite impracticable. Mere subdivision is fairly effective as a defence against submarine explosions; internal armor is still better; external armor has yet to be tried and may prove entirely effective.—P. R. A.