FIGHTING SHIPS OF THE AIR

Dominion, Volume 9, Issue 2777, 22 May 1916, Page 6

FIGHTING SHIPS OF THE AIR

BRITAIN'S NEWEST MACHINES - FOUR DIFFERENT TYPES • (By M. deorges Prade in the London ■... "Times.") • . ' . Prade, the' eminent. French . v's aeronautical expert,. in this article deals with';the ...types of . aeroplanes .. engaged in .the , war. Tho article forms : a valuable';contribution to the . ij literature; of.: aerial, warfare.! > have enabled us to ' establish for': flying. doctrines fouuded on'.oxponence. The present article con"'cerns : itself socially '-with.-, aeroplaues in relation to their various modes of employ-- ' rnent in modernwarfare'. Three general ) ideas.' emerge 'from the facts, and. may ■ serve to guide us in this study::— (1) As military operations develop we •find-more numerous uses for tho plane.(2) At one time,, with a view to simplification, the unification of types was .-thought of. It now. appears, on. the contrary, that in." order to get the best ; Jesuits, it;is'important to, specialise differittt'i'trpos :dt aeroplanes for 7 'different uses. ; ; Finally, technical rules ; of construction are being established day by day . which show that, below a certain power . 'of., motor and certain dimensions of ap- ■ paratus, as well as above a certain power "' or motor and certain dimensions of ap,'patatus, there is no aeroplane of practical v'jse.. . Let us examine these three ideas. Variety of Employment. • :! As tho operations at present in proiress,develop'i't is seen'that the aeroplane 4unsuitable.: foe. all kinds of work. With tfixed. fronts, 'transforming the two' armies ; in presence into real siege, armies, whose Korvices behind the lines are stationary, and -with no limit' to tho development of .material, -'this-- multiplication of tho. uses. of' the aeroplane becomes really prodigious.''lt. is from tho air that-artillery, fire is'-'regulated, after-: the airmen have reand photographed the enemy's -taken -, the - plan of.. 'their -trenches, and'discovered the.) importance ' and the emplacement of. his batteries. It is-from the air- that the (arrival of joinforcementsby rail or motor-car is signalled."- By means, of aerial bombardments, attempts are made to cut, or. at least disorganise, the'. enemy's..communications. " These attempts are made even on the baas railway stations, and,;., further still, on :.tho factories and-, powder magazines ■ whence come.tho munitions.- Duriug the battle the aeroplane flies above the txoops and regulates the lengthening of the fire as the assaulting forces advance. In addition it is .necessary to.secure the mastery of the '■ air by preventing £he adversary from doing the same as ourselves .'in their, and protecting, our own. machines from' the 'enemy.- As fighting machines we have the chasing aeroplane [aiid 'the counter-chaser, which attack and 'defend the working aeroplanes and the captive balloons which watch and aot as police day and night over towns and ' -principal centres cf production; protecting them from enemy aeroplanes and dirigibles. I may be said to-day that flying is the " moat complicated arm, and the most in- ■ finite in its application,. as it combines in itself the doctrines, the needs and the "resources of all the arm's which fight on land. Add to its utilisation at sea, and you will, have some idea :; of the dii'versiljr of _ tho necessary uses '• of tho aeroplane in warfare. I insist on this word, necessary, for the aeroplane gives .to those who know hoiv to make use of it such a superiority, that none of its .resources can -be neglected, and . every ; possible application. soon becomes an in- : Dispensable application. Four Principal Classes.

, Constructors first'. thought. of building en almost - unique type of aeroplane, ,which would serve for' all these uses. -The advantages of this unification were "obvious; greater facility of production,-of .repair, and of apprenticeship., " UnfortuEately it was a, Utopian idea, and had to.'bo. abandoned. Just n9 it is impossible to have one single type of ship, and it has been found necessary to create types for different functions, necessitating .specific, qualities of speed, tonnage, armament, •, and; defence, so it has been found necessary to create different types of aeroplanes. ; - , Certain of the functions which I have just: enumerated demand, in fact, qualities'which not only differ but are opposed; to each other, and practically exclude one another. Thus, the ideal apparatus for regulating artillery fire would be:'one;capable.of.perfecting immobility above the points ■to■ be observed. A /'chaser," " on the contrary, calls for/tho greatest-possible speed.. . Now, in aviation,, the lowest speed-without falling is alwaiys in relation to'the greatest' speed —it is roughly equivalent to 50 per cent. : of-, the maximum'speed. The incompatibility of these'.rtwo. solutions is apparent. ' -In . the same ■ way, a "bomb-drop-per"; must above all. be a weight-lifter, 'a ; quality 'entailing: .considerable' wing surface,".and consequently. low .speed ana a certain difficulty in manoeuvring.

. On -the other hand, it was imposs-'ble to increase to infinity the types of machines, because we have neither an- infinity of models nor of motors, and the qualities of an aeroplane are first of all -determined by the power and weight of ■;its. ! motor,...A, i .compromise was therefore at by the • selection of four prln■i.cipal types of aeroplanes, whioh are, according to their uses—(l) Scouting aeroplanes; 1 (2) artillery obseryation. aero/planes; (3) Bomb-droppers; (4) 'battle-' i plaiies. Each of these types i» divided ' into sub-types, ranging from what may ■be called the minimum of utilisation to •'the maximum of utilisation.

;■ Scouts. - 1; . They are employed for the examination \ . iof tho enemy sector, first by the eye of the i and afterwards by means of At the beginning of tho' | .'-.War these aeroplanes wero obliged to have '/j/large sphere* of action. With trench C;.; Warfare , this range of-action'iias bcea ..' ./«much reduced. It is therefore not neces- ' Wary , for them to carry much petrol. Their .principal qualities are: great manoeuvring facility, ill order to escape from enemy : /artillery fire, and great dunging power, ■to escape from enemy chasers, for, con- ■ j/idering the essential irregularity of their missions, it is almost impossible to supply them with convoys o£ fighting planes •' ■.to' protect them. They should, have on • '/'board. a camera, with special Tens, a maJ chine-gun able to fire in all directions for '• and, finally, a wireless in- . .installation, specially useful in signalling /the advance of troops during important r'"/: battles. The scouting aeroplane is the ' —least specialised of all machines. It is ? .Sthe machine which requires the greatest ;. number of average qualities and especi.,ally great facilities for starting from and j ' landing on all kinds o£ ground. Biplanes i"-of about 13ft. spread of wing, with mo- ■ V'tors of from 80 to 150 h.p., are employed ; -in this .'work. ■ The ideal instrument for directing artil- . lory fire would be a kite I which could be lent up and down at will, and would re-,-main motionless above the enemy target. f ./The apparatus must be able to fly slowly .'and permit tho observer to look in all di- ' erections, for it is not a question of taking photographs. Tho observer must be !/■ able to tell where erory shell falls, and !.. . by wireless immediately regulate the fire I .. iof the battery. . At the same time he /. must escape the enemy's artillery fire and tho attacks of chasers—attacks rendered ... all the easier by the fact that tho artil- ;~ </lery,. observation plane does not leave its i' /sector, and the. enomy knows whero to ; • find it. The apparatus should therefore be light, small, able to climb rapidly, a L. -'good air-craft in all winds, with'an ob- ■'_ \6erver. enjoying the utmost freedom. : <■ Consequently use should be mado of ["■ -'email- biplanes with a wing spread of i - about 30ft., furnished witli two light and { /powerful rotary motors. The observation f -peat be slightly protected, but it j . ,: ;i6 needless to over-arm tho apparatus, j. -|The artillery officer has no time to see i -.whether he is about to bo attacked. He •• passes slowly and continuously over the ;• /targetshe is surveying. On tho other /band, as his itinerary is fixed, nothing is / easier than to protect him by means of a . >choser, turning above him and dominat- >. ■■■■, ing' in advanco the "adversary bent on ;....' • attacking him. Bomb-droppers. ' '• The bomb-dropper is the Dreadnought

of the air. At the same time one must not be misled by the apparent ease of indefinitely increasing its size. Thero comes a moment when the degree of usefulness decreases in proportion to the increase in power. This is where a halt must bo called. It is bettor to distribute the same weight of bombs over a greater number of machines, for by so doing we obtain greater security, augment the accuracy ami rapidity of the bomb-drop-ping, and adtl to the chances of escape irom the enemy. The oomb-dropping aeroplane must include among its qualities a certain minimum of speed, climbiug power, and manoeuvring capacity to enable it to escape froni the fire of antiair guns. 'As for chasers, bomb-droppers must npt be expected to defend themselves against thess. They must be escorted by squadrons which have nothing else to do, composed of machines in which the weight carried does not consist of bombs, but of guns and munitions. Bombarding fleets always include several squadrons, operating on welldetermined itineraries, . known in advance, at.fised hours. Thus, convoying th'em is easy. It has been found possible to group in this way 50 machines, which, flying in a triangle like wild duck, have gone as far as the large cities of South Uermany—Stuttgart, liarlsruhe,. and Mannheim!

These machines must therefore lave very powerful motors—2oo h.p.—a large range of action, and large fuselage, permitting the well-aimed dropping or' bombs by special apparatus. They should also carry a macliine-gun. This is the most diffici. .machine to construct, and the task of he who pilots it is both ungrateful and perilous—long raids over enemy territory.. ' The Battle-plane. This is the 'latest product of military aviation, and it is easy to understand why. In aerial warfare one first of all attempts to make use of one's own aeroplanes. After that one tries to prevent the enemy from doing the same. This gave rise to the creation of.tho "chaser," a light aeroplane, rapid, and climbing very quickly,. so as to doniinate the adversary—a favourable position .in aerial combat. ; TTinally came counter-chasers, whose, object js to defend working aeroplanes—that is scouting planes, artillery directing planes, and uomb-droppers— against enemy chasers. These aeroplanes are. of the same type, as chasers, simply rendered more redoubtable by their armament. Aeroplanes of the fighting type cannot be large, a condition which limits their artillery and its calibre. Most of thorn do not exceed a ton in weight. They are the only single-seated type. The pilot is at the same time the gunner. A twoseated apparatus would Do preierawe. The smaller the machine tho better, provided it can carry a sufficient armament and is built in such a way as to permit firing in every direction. There are two schools: those wlio are in . favour of placing the propeller in front, which augments the speed, but does not allow the use of tile forward machine-gun; and those of the propeller in the rear, which means a slower machine, but more accurate firing. The first school has triumphed, for it is easier ,to, improve the firing than to do without great speed, ■ which alone makes chasing possible. The necessity of making warfare on. balloons, Drachen ("sausages") and Zeppelins has led to the creation of gun-planes, and for fighting Zeppelins at night less rapid machines have been built. They knd in the dark with less.danger. Armed scouting machines are used for this purpose. The questions of aeroplane armament and of aeroplanes intended for night flights merit special study.. Lirffit of Dimonsions.

;>l't only remains to draw the logical 'conclusion on the subject of the size of aeropianes. The largest aeroplane antl the most powerful is the bomb-dropper. The smallest is the chaser. The practical limits of construction, minima and maxima, will therefore be obtained from the-two following considerations drawn from their two special applications-.—An aeroplane is too small, when it . does not even permit a machine-gun to be carried; an aeroplane. beoomes too large when its increase in power and surface is not accompanied by a proportionate increase in weight-lifting capacity. The materials employed in construction are" not capable of indefinite improvement. There comes a moment in a large apapratus when they are no longer capable of supporting the pressure and resistance consequent on the increased mass. At this critical moment one of two things happens. On. the one hand thero inay.be either a reduction in. the factor of safety—which is in general 6; that is to say, each part of the aeroplane ought to be able to support during the static test six times the normal pressure in regular flight. Then the appa-' ratus becomes dangerous. On the other Jiand the structure may be modified and strengthened, when the apparatus becomes heavier, that is to say, it carries less useful weight. Besides, it is impossible to pilot it, for it is too heavy, and docs not answer the rudder.

That is why no giant apparatus exists made from available materials. It is only-the operation of a natural law; giant animals aregradually disappearing Motor-cars have never exceeded a certain weight. Aeroplanes will never, practically, go beyond certain dimensions so lon's as they depend on the same laws of flight, with motors of the sam 9 weight, in proportion to their power:.