Submarine Flotillas of Neutral European Powers.
| Country. | Vessels Built. | Vessels Building. |
|---|---|---|
| Italy | 20 (100–300 tons) | 8 (large size) |
| Denmark | 9 (100–300 tons) | several |
| Holland | 6 (100–300 tons) | 4 (large) |
| Sweden | 7 (150–300 tons) | 3 (large) |
| Greece | 2 (Laubeuf) | —— |
| Norway | 1 —— | 4 (Germania) |
| Portugal | 1 —— | 3 —— |
| Turkey | —— | 3 —— |
| Spain | —— | 3 —— |
CHAPTER VIII
SUBMARINES IN ACTION
Submarines have two great advantages over all types of surface warships; they can become invisible at will—or sufficiently invisible to make gun or torpedo-practice, except at very close quarters, almost entirely useless—and they can, by sinking, cover themselves with armour-plate of sufficient thickness to be absolutely shell-proof. These are the two main points in favour of the submarine. There are, however, many minor features. Although submarines are known in the naval services as “daylight torpedo-boats,” for their greatest value lies in their ability to perform the same task in the “light” as the ordinary surface torpedo-boats and destroyers can do under cover of darkness or fog—that of creeping up close to an enemy, and launching a torpedo unobserved—they have been given, during recent years, so much greater speed, armament, and range of action, that they can no longer be looked upon as small boats just suitable for daylight torpedo attack in favourable circumstances. Their surface speed has been increased from 10 to 20 knots, making them almost as fast as the surface torpedo-boat. This, combined with manœuvering powers and general above-water invisibility, has enabled them to take over the duty of the surface torpedo-boat—that of delivering night-attacks on the surface. After nightfall a submarine attack is almost impossible owing to the periscope—the eyes of the submarine—being useless in the dark.
The increase in the armament of the submarine—from the single bow torpedo tube with two torpedoes of short range and weak explosive charge, to the four bow and two stern tubes with eight or ten torpedoes of long range and high explosive charge—has greatly increased their chances of successful attack on surface warships, first, by giving them four or six shots ahead, then the possibility, in the event of all these torpedoes missing, of a dive under the object of attack, and two more shots at close range from the stern tubes (still retaining two torpedoes); and, secondly, by increasing the distance from which the first projectile can be launched, owing to the increased range of the modern torpedo. There are also the advantages derived from the battery of quick-firing guns installed on the decks of modern submarines. Although at the present time these guns are only of small power they nevertheless afford a means of defence—and even of attack under favourable circumstances—against hostile surface torpedo-boats, destroyers, and air-craft. In fact, a flotilla of submarines could undoubtedly now give a very good account of itself if attacked either on the surface or when submerged by one or two prowling destroyers. The increase in the power of the guns carried by submarines, which will certainly come soon, will enable this type of craft to take up the additional duties of the destroyer—that of clearing the seas of hostile torpedo-boats and carrying out advanced scouting—for which work their ability to travel submerged and in a state of invisibility for distances of over 100 miles makes them eminently suitable.
The enormous increase in the size and range of action of submarines, combined with the improvements effected in the surface cruising qualities, have enabled these vessels to be taken from the “nursery” of harbour and coast defence and placed with the sea-going flotillas and battle-fleets. In the short period of ten years the tonnage of submarines has risen from 100 to over 1,000 tons, and the range of action from 400 miles at economical speed to 5,000 miles. Exactly what this means is more easily realized when it is stated that the earlier types of submarines could scarcely cross the English Channel and return without taking in supplies of fuel, and in rough weather were forced to remain in harbour, whereas the modern vessel can go from England to Newfoundland and back without assistance, and can remain at sea in almost any weather, as was first demonstrated by the successful voyage of the British submarines A.E.1 and A.E.2 to Australia, and has since been proved by the operations of the British submarine flotilla in the North Sea.
In addition to the cruising range there is, however, the question of habitability. In this respect the progress has been equally as rapid. In the older boats no sleeping accommodation was provided for the crew, and food supplies and fresh water sufficient only for a few days were carried. In the latest British, French and German vessels proper sleeping and messing accommodation is provided, and supplies of all kinds and in sufficient quantity to last a month are carried. Although work on these craft is still very cramping for the crew, the increase in the deck space and in the surface buoyancy has greatly minimised the discomforts of service in the submarine flotilla.
With regard to safety, it has already been shown that a submarine is only held below the surface by the power of her engines and the action of the water on her diving-rudders. This means that in the event of anything going wrong inside the vessel she would automatically rise to the surface; but should the hull be pierced in any way, either by shot or by collision, and an overwhelming inrush of water result—overcoming the buoyancy quickly obtained by blowing out the water-ballast tanks—then the vessel must inevitably sink, and the question of whether or not the crew can save themselves becomes a problem to which no definite answer can be given, although a special means is provided in all modern vessels belonging to the British Navy. Speaking generally, it may, however, be said that if the disaster occurs suddenly, and the vessel sinks into very deep water rapidly, the chances of life-saving are extremely small; but if the water is comparatively shallow, as along the coast (100 to 150 feet), the likelihood of many of the crew being able to save themselves with the aid of the special escape helmets and air-locks is fairly good.
We now come to the most important improvement made in the fighting qualities of these vessels since first they came into being, viz. the wonderful increase in the surface and submerged speed. In the older craft the surface speed did not exceed 8 to 10 knots an hour, whereas it now amounts to 16 to 20 knots, and the submerged speed has risen from 5 knots to 10 to 12 knots. It is a little difficult for any but a naval man to realize exactly what this increase in the speed of submarines really means, and it is equally as difficult to adequately describe it here in non-technical language. It is a mere platitude to say that in order to attack a surface warship the submarine must first get within torpedo range of it; and yet it is on this very point that the strategy and tactics of submarine warfare revolve. A clever naval tactician once described the submarine as a “handicapped torpedo-boat.” The two points on which he based this opinion were—the (then) slow speed of these vessels compared with that of the surface warship, and its almost total blindness when submerged. These two defects were for some years the principal drawbacks of all the submarines afloat; but since that naval expert pronounced submarines to be “handicapped torpedo-boats,” great changes, great improvements have been made. The speed of the submarine has increased by over 100 per cent., and they have been given longer and wider range of vision by the introduction of two and three improved periscopes instead of one elementary instrument. Nevertheless, the speed difficulty is still a very real one, as will readily be seen when it is taken into consideration that the speed of a submarine when attacking submerged is frequently only half, or even a third, of that of her enemy. In order to more clearly illustrate this and lift for a moment the veil of secrecy which enshrouds the methods of attack adopted by this type of craft, it will be necessary to describe what is known as the right-angle attack.