For that reason many military men even thought that the aeroplane, because of the velocity at which it moved, could not be of much value other than for scouting, and as no guns had been successfully mounted on aircraft before the World War, the aeroplane was not regarded as an offensive weapon. Indeed, that was one of the developments of the war.
The first attempts to mount a machine-gun on an aeroplane were made in France on a Morane monoplane. In order to shoot over the propeller a steel scaffolding was erected, and the pilot was supposed to stand up to sight his gun. This was impracticable, and the structure retarded the vision of the pilot and the speed of the aeroplane.
In the early days of the war pilots seldom flew over 3,000 feet high, and since there were no machine-guns mounted in a practical way, the pilots could only content themselves with firing revolvers at one another. The only thing they had to fear was rifle-shot and the trajectory of artillery. The few antiaircraft guns had no greater range than 3,000 feet, and, as a matter of fact, most of the reconnaissance work done at Verdun in the first six months of 1916 was at 3,000 feet altitude.
The first historic record of a machine-gun mounted on an aeroplane was in the despatch telling of the death of the French aviator Garaix on August 15, 1914, by the aerobus Paul Schmitt. Garaix had 200 rounds of ammunition. In December of that year the 160 horse-power Breguet piloted by Moineau mounted a machine-gun. The French pusher Voisins, with no obstruction of vision to the gunner in the nacelle, afforded an excellent opportunity for the use of machine-guns. Moreover, most of the aeroplanes brought down in the early days of the war were the victims of engine trouble or shots from rifles on the ground. A staff report of October 5, 1914, of the Germans relates that the French aviator Frantz, flying a Voisin with his mechanic Quenault, shot down a German Aviatic plane with two aviators from 1,500 metres altitude, killing the two Germans. For this feat Sergeant Frantz received the Military Medal, the first decoration given a French flier in the war.
On October 7 Captain Blaise and Sergeant Gaubert, in a Maurice Farman, with a rifle shot down Lieutenant Finger, a Boche who had defended himself with a revolver. Captain Blaise expended eight shots before he got the German flier.
The first recorded equipment of a machine-gun on a German machine was on October 25, 1914, when a Taube near Amiens opened fire on a Henry Farman machine piloted by Corporal Strebick and his mechanic, who were directing artillery-fire. The Germans first used a Mauser gun for their aeroplanes.
Meanwhile, the need for having a machine-gun fixed stationary on the aircraft and armed by manœuvring the aeroplane became more evident. Roland Garros, who was the first to fly across the Mediterranean Sea from France to Tunis, Africa, mounted a gun to shoot through the propeller on February 1, 1915. In order to protect the blades from the bullets, he had the propeller-tip covered with steel. Thus, when the bullets hit, they were deflected. Only 7 per cent hit the blades, however.
This was a crude way of mounting the gun, and it was Garros’s mechanician who worked out the method of gearing up the machine-gun so that it shot its 600 bullets between the revolutions of the propeller. This enabled the so-called single-seater scout tractors, with propeller in front, to fly armed with a machine-gun mounted over the hood of the engine, directly in front of the aviator. It was also the beginning of the use of the aeroplane as a fighter in aerial duels and in contact patrol of later days when it descended to attack troops in the trenches and trains on the tracks.
January 1, 1915, was the date of mounting the first Lewis machine-gun on a Nieuport aeroplane to shoot over the propeller. The Germans copied this with their Parabellum light gun, but it was not till July, 1915, that the German Fokker first appeared with a synchronized machine-gun mounted on it. Since a propeller revolves 1,400 times a minute, a blade passes the nose of the gun 2,800 times a minute, and the machine-guns were geared to shoot about 400 shots a minute, so that one shot passes through to every seven strokes of the propeller-blade. Sometimes, however, as many as two guns were synchronized to shoot through the same propeller. A push-button on the steering-bar fires the gun while the pilot keeps his eye on the enemy through the telescope in front of him.
The Lewis gun is an air-cooled, gas-operated, magazine-fed gun, weighing 26 pounds with the jacket and 18 pounds without. The facility with which the gun can be manœuvred into any position or angle makes it a very efficient aeroplane gun. The ability of this gun to function automatically, and the speed with which it operates, is due to the use of a detachable drum-shaped, rotating magazine which holds 47 or 97 cartridges each. When the magazine is placed in position it needs no more attention until all the cartridges are empty, when the magazine is snatched off and another is stuck on. This gun is the invention of Colonel Isaac Lewis, a retired American army officer.