THE UNDER-WATER FOE

Dominion, Volume 7, Issue 2263, 24 September 1914, Page 7

THE UNDER-WATER FOE

SUBMARINE FIGHTING SHIPS '•.;.- '■.-■• ;)"....' ■ ' RECENT PROGRESS REVIEWED ' Tho fact that German submarines fcave succeeded in accounting for three British ships in the North Sea will surpriso no one who has followed the recent developments of under-water craft, . for they have reached such a pitch of efficiency as to constitute a menace to every blockading fleet. The episode of the destruction of the submarine 1117' by the' British cruiser Birmingham ehowed the. limitations, in some respects, of -this form of attack, but; circumstances must arise at times from weather conditions and otherwise which confer the initial advantage upon sub-, ■marines operating against a blockading ileet. In the French , naval manoeuvres of- 1913 submarines operating with, a, ■• defending force attacked the blockaders so successfully 1 that they were compelled to retire to a distance which enabled ,■: the] interned warships to escape. The ■ available particulars of the successful attack upon the British cruisers in the ■North Sea do' not suggest that the cir- . cumstances were in any ■ way remarli!- ' able. Old ships, of tho type to which ; the three cruisers, belonged, would naturally' be entrusted with the dangerous task of keeping in comparatively closetouoh with' the blockaded enemy, and assuming that the cruisers were so engaged, the attack which in' this instance was successfully driven home 1 would.be an enterprise well within, the capabilities of submarine- .flotillas possessed by all the naval : Powers. : All naval countries maintain, strict reticence regard«,g the design and lighting power of; the units in their submarine flotillas, but.so ; far as is known . Germany does not possess any superiority in this branch of her navy. ■ Oil the contrary, 4he' began tho construction of submarines or submcrsiblos five or six years after Franco and Britain possessed .'craft of this tj-pe, and according to the latest available figures ' Britain possesses moro th,..i three times as many eifJcfcive submersibles'as Ger- : many, and Franco more' than twice as . many. . The .position appears to be that : at their present stage of development submersibles are. much more effective in coast defence work than in operations ." ovbr a more "extended range. It is in connection "with to operations of her •submarine and destroyer, flotillas that : the possession of" the sea-fortress- of Heligoland is , chiefly of'-importance'•' to : Germany. This strongnold affords the small craft a convenient base,. and in the shelter of its fortified harbour several' flotillas can "lie safely in any . weather. •* ; . . : ; .

Germany's Late Start. According to the.Berlin'corrospondent ■?i Navy," writing in April last, the first German submarine boat was put afloat- 'in / August, ■ 190G (other autiionities' say ; . 1905),' ■ and'■. christened'Ul." At that date tho fleets of. several Powers, notably those of -FVaiice • and England, already, included a 'large, number of submarines; but Germany, traditiphally 'conservative towards all naval innovations, hesitated long before committing'herself. The most contradictory statements were made , about the behaviour of "Ul." One account spoko ' of the, boat having behaved admirably . on trial, but: a subsequent report, which had authority behind it, declared it to be dangerous in a Tough sea. On the whole, naval opinion remained.unfavourable, and;for tho.'iie.3&,ißur A or fiyoyearatire'. submarino" igotilla.' increased .-"very siowly. Nevertheless,; tho Navy Department had obtained a yearly grapt of some £250,000 for -experiments ■ in. submarine navigation, Tend with -4*113 nioriey built improved boats. They wdi'e • all constructed, from designs prepared hy Messrs. Krupp, at their German yards, on the Baltio, though later on. the Imperial Dockyard at Danzig took a ]iand in the work. ' A great mystery is still made of the actual uujnber built. The."Nautical Annual" up to 1.912 gave. 'the 'as 12, but in "its 1913 edispeaks of 23 a-s oeirig .completed. Obviously/ therefore, progress'has been very rapid during tho last, two or three, The new Navy Act of 1912 pro-' vides for the annual construction of six boats, beginning with that yeai - , so ■ that before tho end of 1914 at least 18 , l submarines will be in hand.' Taking two • years as the average period occupied m building, it would seem that by 1920 the German submarine. v flotilla woufl have reached its legal 1 establishment of 72 boats—a remarkable figure, considering that.it is only six years since the launch of the first German boat. ■ .>•: Submarine or Submersible. ; "Strictly speaking, .there are no GerD.'an submarines,- they aro all'submerBibles; that is.-to say, they are vessels fitted with powerful engines for surfaco navigation, possessing an extended .range of action, and able to keep tho sea for Jong periodSj whereas the sul)- ' marine proper is a. boat iirwhich radius niid seaworthiness are subordinated to uiider-water manoeuvring. .This; differentiation, of a type finds its counterpart in-surfaeo,torpedo-crait, as witness tho coastal and sea-going boats. In ing it ■ may be' mentioned that prac- . tically every navy in the world is now building submersibles in preference'to submarines, though 'submarino 1 is still retained as a convenient geuerio teni for all under-watcr fighters. . "Any authoritative comparison 'between German and British submarines of equal date is rendered.impossible by reason of the reticence displayed in both countries in regard to this typo of con- . etruction. It-was reported by a Berlin paper last year that the boats building under -the current programme were of 800 tons, with two Diesel motors, developing 1800 h.p. in the aggregate and capable of giving a speed. on the surface of 17 knote, the speed submerged being estimated at twelve knots. Each boat was to bo armed with two- 14pounder guns, on high-angle mountings. It is difficult to say, however, whother these details are to b*9 relied upon. Equally little is known in regard to_ the latest British types, but the Admiralty are believed to favour a.policy of, developing tho submarine as well as the eubmersiblo, thus providing a certain number of boats designed' mainly for local coast defence; in addition to the bigger sea-going crnft which are ' oble to operate on the high seas.' Fighting Value of the Submarino. "Public opinion is inclined to place tin exaggerated value .011 the submarine, thanks to the highly sensational stories of its prowess, which ar6 printed in the newspapers, Wonderful progress has no doubt been made, and it .is certain that the best brains in many countries are devoted to the perfection of submarino navigation. Yet there are certain inherent difficulties, to overcome which definitely limit tho efficiency, of the type at the present stage of science and engineering. By greatly, increasing the size; it might be possible to givo a submarine a surface speed equal to that of modern battleships, i.e., 22 to 23 knots, thus enabling it to accompany a fleet at sea.; The existence of such boats would lead to the modification of accepted principles of strategy and tactics. Submarines of this typo may—probably will —be in service .1 few years hence, • for the steady improvement of tho heavy oil motor, leading to higher, power and reduced weight, is slowly but surely raising tho speed at which eubmarino boats can travel on the surface. There has not, however, been corresponding progress in relation to tho machinery for cruising below, water. The enormous weight of the accumulators sets a .limit to the power of tho. -electrical plant, which, in epite of its uneconomical operation in proportion to tho weight it nre-OTipts. et-ili. monopolises the field

as the only thoroughly practicable plant for .submerged travelling. It may 'be doubted whether any submarine boat has a speed below water of moro than 13 knots, though several French aud.ltaliaii craft nave higher legendary speeds, in some of their new boats the French have reintroduced the steam engine- for surface and submerged running alike, but its uso is-certain to bo attended with discomfort and perhaps danger to tho crew when tho boat is below tho" surface. Another, solution of the problem of !how to increase un-der-water speed has been proposed by an Italian engineer, Sigiior Del Pro-post-o. His plan is to' utilise a Diesel-four-cylinder engine'as a combined surface and submerged motor. The dilfi- • culty of creating an adequate supply of air for tho eugino when the boat is below the surface is to be mot by providing an' air pump, which, driven by tho motor during tho surface run, will store up a largo reserve of air For the use of the motor when tho boat ■ dives. This arrangement requires _ a great number of flasks for containing the compressed air, and tho weight and ■ space occupied by them is a 6erious defect. Moreover, the exhaust gases'of the motor, rising to tho surface, would betray the presence of the submarine, just as tho course of a torpedo can be marked by the line of air bubbles. Nevertheless there is reason to believu that the Proposto system is receiving the attention of more- than one navy.

: High Spaed Below Water. "That" some satisfactory " method of propelling submarines at high speeds below water'will'eventually be discovered is almost certain. When that has been done, the power of the submarine as a weapon ot destruction.will be augmented to an incalculable extent. At present, even tno blowest battleship is virtually -saEe from under-water attack when Steaming at its best speed. The subniariuo' is too slow below the surface to pursuo its prey, while if-it rises it becomes exposed to gun-iiro. So > it has perforce to lie in wait for its viothns. or to fall upon them unawares when they are at anchor or steaming very slowly. A fleet of ships maintaining a blockade would represent tho ideal objective-of submarine .attack, and the writings of General von Bernha'rdi and other strategists show that Germany places great reliance on her submarines as an antidote to a close blockade of her coasts. A flotilla based on Heligoland would be admirably situated for this work, a fact which goes far to explain the successful '.-efforts , ' of Germany to convert the island -into a naval stronghold of the first rank."- . ■" . ■' '

SUBMARINE DEVELOPMENTS. COAST DEFENCE AND SQUADRON j : SHIPS. Tho development of the submarine'is reviewed by IAI. Maximo Laubeuf (late Chief-Constructor to the French Navy) I in tho /"Navy League Annual" for. 1913-14. He remarks that submarines havo not escaped the tendency which makes itself so strongly felt just now, towards increase of tonnage, and that as in the case of destroyers,- tho increase in size has not been accompanied by a corresponding increase in torpedo armament. In France the small submersibles 'of ,167-210 tons, built to M. 'Laubeuf's plans in 1900-01, had -four outer torpedo-launching apparati for 18« inch torpedoes. The latest French ship, of. SOOrIIOO tons, has eight tubes. : M. Laubeuf divides submarines, into two -classes, squadron .submarines .and defensive or coast-guarding submarines. The latter,' he says, should be ships of moderate- tonnago, and being inexpensive,, can be constructed in large numbers. They must bo well armed, but need not realise very .great: speeds, nor, have a very large radius of action when navigating on the surface. . Ships of this class are .possessed by almost every naval Power, Britain. France, Germany, and "Austria included.. '';'• •■■*-•■ The submersible type was invented by M. Laubeuf in-1897, and the first specimen, the Norviil, was launched in October, 1899. The first submersible turned out by the Gerraania-Kriipp works was launched on August 30, 1905. . , (.ong-Dlstance Voyages. M. Laubeuf gives. the following par-' ticulars qf long-distance voyages accomplished by submersibles.' ■ The Brumairo. (a- vessel of 400-550 tons .displacement) mado the voyage i.from Dunkirk to Bordeaux in the month of July, 1912, or 800 miles, ie 72 hours, without calling at a port, at an average speed of 11 knots.-' ; . < The Faraday, from September 28 to' October 5, .1912, made the passage from Hochefort to . Toulon, ,or 1730 miles, without putting in, at ah average speed iot 11 knots, notwithstanding two days of bad weather. This latter, distance constitutes,. M. Laubouf believes, a record in distance covered by a submarine. : without putting in at a port. ! n " tlle French naval manoeuvres of Idl3 submarines were employed with great success against a- blockading fleet and otherwise, and their performance vvas thus commented on by tho naval expert, (J. Pierreval, in the- "Moniteur de la Flotte":- "Theactioh of the submarines has been absolutely remarkablo. JNot only did they before Toulon inflict upon the blockaders euch serious losses that in reality the party B (with wliich the submarines were operating) could have passed through the breaches they opened, not only did they prove ■ at Bpnifacio that straits guarded by them Would not be passed, but their action on the high seas (when they successfully' attacked armoured ships at a dista'nee of one hundred miles from their base) has proved i'or the first time that they were capable to fill a more important rolo." ' AVhile M. Laubeuf considers that sub-raa-rines of. the smaller type suitable for defensive or coast-guarding work have fully established their position in naval warfare, lie thinks most of the larger submarines of 700 to 800 tons, built or building in France, Britain, and Germany, unsatisfactory. These ships, ho remarks, cannot accomplish'much more than the coast-guarding ships of 400 to 500 tons, and. they are too slow and lack the nautical qualities that would enable them to accompavy the squadrons of sea-going ships. The very latest 6hips of this type in France and England (which apparently lead the way) aro intended to have a speed of 20 knots on the surface and 12 knotswhen submerged for battle. M. Laubeuf declares that both speeds are insufficient for the purposes aimed at. Until submarino snips can attain a speed of 23 knots -on the surface, and 15 knots submerged, he says, they will bo insufficient to fill tho rolo of squadron submarines, and will only impede the armoured ships. At present the difficulty is to construct sufficiently powerful motors of relatively small weight and size, but tho improvements made in recent times indicate the possibility that within -a fow years tho necessary motors may bo available. So far as those larger submarines are concerned the tendency is towards a ship of some 1200 tons 'displacement when submerged, having a surface speed of 23 knots and a speed when submerged of 15 knots. When such ships can bo constructed tho destroyer may disappear from modern fleets. "Meantime tho smaller coast-defence submarine, within its limits, is a fighting machine- of proved efficiency, and the destruction of tho three- British cruisers in the North Sea is a. positive indication of tho fact. • Relative Strengths. Twelve years is accepted as the effective lifq of a submarine, and according to tho Navy League. Annual for 1913-14 tho Powers mentioned possess this year the following numbers of completed submarino craft, less than eleven years of age:— British Enipiro 79 Franco 68 Germany 24 It was reported in tho German "Snliifl'bau" recently that the new Bri-

tish submarines of tlio "G" claes would bo a very big stop in advance of anything yet built in .the way of underwater craft . The details given in tho German publication credited tho ships in, question with a displacement of 1500 tons, and ongines of GSOO h.p. giving a &urfaco speed of 24 knots and 12 knots, with 2400 horse-power, subThe radius of action was said to be 2800 knots—equal to a voyago from Portsmouth to Gibraltar and back with fuel in hand—and the armament eight torpedo tubes for 21 inch, weapons and four -1-inch guns. The "F" type of British submarines are- of only 1200 tons displacement, and liavo a speed of 20 knots above and 12 bolow water, with an armament of twelve tubes, so that the units jaf tho later type must be greatly superior in fighting power. "Schiffbau," it is stated, Las a habit of boing accurate with regard to details of new ships.

Guardian Aeroplanes. One weakness of the submarine is that it can often be readily observed and attacked from the air. Touching upon this aspeot of the subject in tho 'Navy League Annual" Mr. 0. G. Grey (editor of the "The Aeroplane") remarks: "There is one phase of utility for aeroplanes which, deserves special mention, namely, their efficacy as a guard against'submarines. I gather that the submarine" is a continual nightmare to every battleship. The aeroplanes 6liould be regarded as the "four angels round my bed , of our childhood's prayer. The air-scout. can see tho submarine when no one else can, and generally when the submarine cannot see him. In 1912, when a submarine attack was mado up the Fifth of Forth, the submarines got up to Rosyjh--- unseen by anybody except the -aeroplane pilots, who had them in sight all tho way. Into ■ anything liko clear water an air-scout can see vertically to any depth to which niost submarines can divo at present, and when a submarine is- running; with her periscope showing the shaft of tho periscope leaves a wake which is easily seen from above, ./though not from any distance at an angle. Thus, both in tho high seas and for coastal, defence, the aeroplane as a detector and destroyer of submarines has a distinct place in the scheme of things."