DOVES OF WAR

Evening Post, Volume LXXXVIII, Issue 60, 8 September 1914, Page 3

DOVES OF WAR

THOSE TERRIBLE "TAUBES" SECRET OF GERMAN AEROPLANES MORE RELIABLE ENGINES, (By "Autos.") It never does for an individual or a nation to underrate an opponent. Pride of that sort is a perilous thing in war — especially modern high-speed war, -when there is rarely time to correct a mistake before serious damage is done. That is, with reservations, somewhat the position the Allies find themselves in to-day with regard to German aeroplanes. In the early stages of the war ■ — say, the first fortnight — had you men tioned aircraft to the man in the street, he would have told you, with even mure assurance than he usually displays, that if there was one thing certain in a comparison of strengths it was the French superiority in the air. Be will not be quite so firm on that point now. Just lately there have been a number of cable messages — a bunch of them in Saturday's Post— indicating that on the whole the superiority is with Germans. A good deal is heard of the exploits of "taube" monoplanes, reconnoitring the trenches of the Allies and directing the fire of artillery. If one side can do that with comparative impunity, then it must be' admitted that it holds, temporarily, let us hope, the mastery of the air. There is no need to enlarge on what the mastery of the air means in a modern war. If one side can see all the time what the other side is doing, and the other side is unable to pay a return visit, then one might fairly conclude it is going to make things a good deal easier for the side with the argue eye of the aeroplane, and a good deal harder for the side with that eye temporarily obfuscated. NOT MAN BUT MACHINE. One does not desire to emphasise this too much just now. The evidence isnot complete enough to make out a case of failure against the Allies. Man for man, both the British and the French aviators are probably equal, if not superior to the Germans. For brilliancy of exploit, dash, nerve, skill — ir short, airmanship — the great French pilots still remain unsurpassed in the world, and Britain in her Flying Corps has a devoted band of admirable airmen. But it is not the man in this instance; it is the machine. Some years ago, when flying was a nine-days' wonder and not an everyday occurrence, somebody said that this aerial locomotion was 25 per cent, the machine and 75 per cent, the man. That iros when it was a feat) chronicled all over the world to remain aloft for as long as it takes the Main Trunk express to get from here to Palmerston. Only the other day an aeroplane — let us frankly admit it was a German aeroplane — kept going in the air for 26 hoars without coming down. Thus, it is safe to say that the ratios are reversed now and flying is fully 75 per cent, the machine and only 25 the man. But it is a, German machine; neither the French nor the British airmen in their planes have come anywhere near this marvellous record of endurance. When it is added that to-day the Germans hold nearly every other record, it will be seen that things have changed since the man in the street could say correctly that the French were unchallenged masters of the air. In the last two years they have tended to rest on their laurels so far as military aviation is concerned, while the Germans, who first, under the influence -of the Kaiser, had been disposed to put all their money on the Zeppelin to the exclusion of the aeroplane, hare now more than made up the lost ground. WHAT MAKES THE 'PLANE FLY. What is the secret of German progress in aviation? It is expressed in these words of the special correspondent of l' The ., Aero '" writing from Berlin in May, 1912, just when the German aeroplane beginning to soar from obscurity '.—" The noteworthy features are the dominance of the German motor and the great improvement made of late in the body of the machines. Greater stress is laid by the German military authorities on reliability of the- aeroplane than upon speed, and the development of the engine is the chief aim of everybody concerned." It is in the development of the engine that German success lies. It is an axiom that mechanical flight depends on continuous motion through the air, and that continuous motion, horizontally or upwards, can only be maintained by the continuous output of power by the engine, varying within small limit*., and made effective by. transmission to the air through the propeller thrust. If the engine stops, the aeroplane must fall ; if the engine slows down beyond a certain speed, the aero-. Diane must fall, though naturally more gradually than in the former instance. If flying, therefore, is to be more than a, mere freak of chance, an engine is wanted that will keep going, and keep going, at a speed with the least possible variation. When an aeroplane flies for twenty-four hours on end, it means that during that period not only has the engine not stopped — or, at any rate, for not more than a few seconds — but also that it has not even varied more than a few" horsepower from its maximum. Flying, therefore, is a matter of machinery for the most part nowadays, and it is because the Germans have developed a type of engine that is, apparently, more reliable ihan th» type of engine in use by the French and British that they have obtained the success suggested in the cable news. THE GNOME— GOOD POINTS AND BAD. The standard French motor for aeroplanes is, of course, the famous Gnome rotary engine. In itself it is one of the cleverest inventions imaginable — seven or more cylinders, like the spokes of a wheel revolving round a stationary crank shaft — and the workmanship and material of a Gnome motor is like that of a highgrade watch. In the early days of flight it was the Gnome motor that really made aviation practicable. Up to a year or two the name of Gnome was synonymous with nearly every achievement and record in flight. It was Gnome first and the rest nowhere. This gieat French motor, the invention of Sequin Freres, is a beautiful piece of mechanism, but as an engine for long aerial voyages, long in distance and long in time, it has> distinct limitations and defects. In the first place, it is a peculiarly variable motor on account of its delicacy. Some days it will go perfectly like an eight-day clock ; then for some cause often difficult to locate it will jib. In general it requires men to look after it who have made a special study of its idiosyncrasies. At the same time at its best the Gnome is unequalled for power combined With lightness. Gnome engines have been built giving out one horse-power for every two pounds of weight. This is far better than the best German engine, where four pounds to the horse-power is not above the average. But what the Gnome gains in small engine weight it loses in extravagant consumption of fuel and lubricant. It simply eats up petrol and castor oil. This is a drawback to protracted flight, as it means carrying enormous tajiks of fuel and

lubricant, far more than would be required for the standard German aeromotor for the same engine power and distance of air-trip. The great majority of the French military- aeroplanes are equipped with the Gnome, and also many of the British machines. JUST THE OLD MOTOR-CAR ENGINE. It was probably for patriotic motives that- the Germans rejected the Gnome motor in the first place, just as it was the same reason that led them to devise special and typical German machines in the "taube" monoplanes apd the various "arrow" biplanes. These, is may be explained here quite briefly, go far nearer to reproducing the shape of that nntural flier the bird ("taube" meaning dove) than do the French and British aeroplanes. Whether they gain much by this is still in doubt. But there seems to be no question that they have gained something by their choice of type of engine. Instead of originating something entirely new and strange like the gnome motor the Germans turned to th© type of petrol engine which has already become perfectly reliable in the motorcar. Most people are familiar with the appearance of a motor-car engine; you have only got to lift the bonnet of a motor-car to havj* a »uflicieni under standing of the vital difference between the typical German and French aeroplane motors. The engine that drives these terrible "taubes" and deadly •'arrows" through the air so remarkably as to attract the notice of war^ correspondents and be deemed worthy of a cable message, is simply a gloriried edition of our old and tried friend the motor that drives the taxi and the grocer's delivery van about the streets day in and day out all th© year round. By the most careful attention to detail and the choice of the best materials the Germans hay© succeedtd in cutting ouv the superfluoas weight of the motor-car engine without losing any of its economy, efficiency, and reliability. There is really nothing more to_ be said, except that the principal engines used in the German military aeroplanes to-day are made by the manufacturers of the best known German motor-cars, such as the Mercedes and the Benz, the Argus and the N.A.G. A corresponding type of aero-motor in England is the Green, which Harry Hawker used in his flight by water round Britain, but unfortunately the war caught the British War Office still experimenting, and the majority of the Bntish machines in the field will be fitted with the Gnome, the Renault, or the Austro-Diamler engines, of which it tannot be said they are "mad© in Britain." There is some comfort in this : that no aeroplane, whatever may be its type of engine, is safe from gun-fire and rifle-fire from the ground, and we can only express a hope that when next the "taubes" and the "arrows" fly over the Allies' lines they will get a very warm reception.