Page:Popular Science Monthly Volume 91.djvu/95

 Popular Science Monthly

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��machine-gun implied the building of an airplane able to mount and fire it. Now it was soon found that the pusher type of airplane, which carries its propeller in the rear, is not so fast as the tractor, which carries its propeller in the front. It was also found that for fighting, at least, quick-maneuvering ability is highly essen- tial, which implies a small, high-powered machine carrying only one man. Here was a very difficult technical problem to be solved: The fighting machine had to be a tractor for speed; the propeller in front necessarily interfered with the proper manipulation of the machine-gun; the officer in the pilot's seat had not only to keep his machine on an even keel but also to fight his gun. Had the military strategists of Europe been told before the war that these were the conditions that would have to be fulfilled, they would have dismissed them as absurdities at once. But by the middle of 1916, the requisites were so clearly recognized that they were met, and that with astonishing ingenuity.

The Fast Fighting Machine Appears

By the end of I9i5ithad been discov- ered that of. all the flying m ac h i n e s used by the Allies, the. fast racing monoplane of Morane- Saulnier in France and the speedy biplane racers made by the two firms of Sop- with and Bristol in England were best adapted for air fighting, sim- ply because they had speed and dragon-fly ma- neuvering abil- ity. They were given more speed by equip- ping them with engines of one hundred and

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Fast fighting machines have engines of 150 horsepower and more, and are strengthened to withstand enormous stresses

���fifty horsepower and even more, and they were strengthened so that they might withstand the enormous stresses set up in flight by engines so powerful.

Curiously enough, the problem of firing through the propeller had been solved before the war by some imaginative in- ventor with more vision than is given to academically trained generals, and curi- ously enough it was solved in both France and Germany simultaneously. The solution was this: The gun was rigidly mounted in front of the pilot, and it was mechanically connected with the engine. A propeller revolves at about 1,200 revolutions a minute; a machine-gun fires at the rate of 600 shots a minute. Let the engine fire the gun at just that fraction of a second when no propeller blade intervenes — that is the solution.

Because the gun is rigidly mounted, the air fighter must turn the entire machine toward his German enemy to fire it. The enemy does the same; for the German Fokker, an adaptation of the French Morane-Saulnier, is similarly designed and equipped with a fixed machine-gun.

When these fighters first ap- peared on the side of the Allies they drove every- thing before them. It was impossible for the slower Germans to cope with them. Then the Fokker appeared. The m a- chines of the Allies were made still faster; the fighters be- came more skil- ful, moredaring; fighting tactics were evolved. As a result, the Allies have not only caught up with each Ger- man improve- ment but have surpassed it.

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