THE BRITISH ARMY AEROPLANE.

After carrying on a series of experiments last September and October, the aeroplane designed by Capt. S. F. Cody, of the British Aeronautical Corps, was remodeled and has lately been given some further trials.

As first designed, this machine was similar to the present aeroplane. The dimensions of the planes were 40 feet long by 7 1/2 feet wide, and they were spaced 8 feet apart. Movable wing tips were arranged at the ends of the lower planes, the horizontal rudder being placed in front and the triangular vertical rudder at the rear. There was also a small triangular vertical surface above the main plane at the center. The flights made by this machine were 304 feet on September 29, 200 feet at 10 feet elevation on October 14, and 1,200 feet at 30 feet elevation in 27 seconds on October 16. In the last flight the machine tipped to one side and was smashed when it struck the ground.


End view of the British army aeroplane
Note the vertical rudders in the front and rear, the propellers at the front edge, and the vertical gasoline tank and radiator between the planes at the center and toward the rear. The flag and streamers show the direction of the wind.

THE NEW AEROPLANE OF THE BRITISH ARMY AERONAUTIC CORPS.

The planes of the new machine are about one-third longer than those of the old one, and the total weight of the machine is some 1,500 pounds. The same 50 horse-power 8-cylinder Antoinette motor is used. It is placed at the front of the lower plane in the center, and drives two peculiar propellers located each about 4 feet on either side of it at the front edge, by means of chains. The movable wing tips have been placed beside the horizontal rudder, so that they are practically extensions of it. One of these turns upward and the other downward when the steering column is swung from one side to the other, while a forward and backward motion of the steering column turns the horizontal rudder. The vertical rudder is placed at the rear as before, and is worked by turning the steering wheel. The 3-gallon gasoline tank is placed above the motor, and the radiator is located vertically behind the aviator's seat, which is back of the motor. The motor is mounted upon a substantial chassis and strong springs are interposed between this chassis and the axles of the running gear for the purpose of absorbing the shock when the machine strikes the ground.


Three-quarter front view of the aeroplane.
The movable tips at each end of the horizontal rudder, the motor and propellers, the three-wheeled chassis with buffer wheel in front, are all visible in this photograph.

The most notable feature of this aeroplane is found in the two propellers. These are of a peculiar type similar to that described in the SUPPLEMENT of December 19,1908, by Mr. Sidney H. Hollands. The peculiar feature is that the blades are broader at their base than at their ends, the width at the base being 24 inches, and the width at the outer end being but 5 inches. The length of the blades is about 3 feet. They are made of aluminium and are curved somewhat like a sugar scoop. Each one is mounted on a strong piece of steel tubing. Mr. Cody, as well as Mr. Hollands, both claim to have found that a blade of this shape gives better results than the usual form of blade, which is narrower at the base than at the tip. It is only in this respect that Mr. Hollands' propeller resembles that used by Mr. Cody on the British army aeroplane. In a letter to English Aeronautics Mr. Hollands describes his propeller (with which he claims to have obtained a thrust of 26 pounds per horse-power) as having two "narrow-tipped blades of a special conchoidal (or irregular crescent-shape) cross-section, set to pitch-angles of maximum efficiency. These angles, together with the other foregoing essential features, were all separately determined by a long and careful series of comparative experiments. The blades have a twist, and the pitch is 0.7 of the diameter. It is most efficient at high speeds (the driving torque being relatively very small), and the essential features of the design lend themselves to strength and rigidity. It is constructed wholly of high-grade steel, and the 2 meters diameter type weighs 13 pounds, with a factor of safety of six, at 1,200 revolutions per minute." Mr. Hollands claims that his propeller is superior to those used on the army aeroplane and that it was designed some years before the propellers of Mr. Cody.

According to a cable report, the first test of the remodeled aeroplane occurred on the 20th instant. Two short flights were made by Capt. Cody successfully, but the third one was terminated, after the machine had traveled some 300 feet at a height of about 20 feet from the ground, by the buckling of the horizontal rudder, and the aeroplane fell heavily and was badly wrecked.


Originally appeared in Scientific American, 100,, January 30, 1909, p. 96.

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