Glenn Curtiss being hoisted aboard the battleship Pennsylvania in San Diego Harbour after alighting alongside in his hydro-aeroplane.
In general outline the aeroplanes in use to-day differ greatly from those seen several years ago, but the difference is in form rather than in principle. There have been many improvements, of course, in construction, control of the fliers, and in the powerful engines that drive them. In fact the tendency of aeroplane builders has been to adopt the successful devices on other machines rather than to work out original ones.
The most noticeable change in the present-day aeroplanes is the way in which builders nowadays are enclosing the bodies and landing framework in canvas or even light metal, so that they shall offer as little resistance to the air as possible. It gives the machines the appearance of being armoured, as will be noticed from the pictures of the new planes, so the term has come to be used in that sense, although, of course, the covering would not protect them against bullets. This armour has become particularly popular with the designers who are making aeroplanes for the French Army, and at the recent military tests in France most of the machines were covered to some degree, and many of them looked for all the world like great long-bodied gulls or mammoth flying fishes.
Several aeroplanes have been equipped with twin motors and double steering systems so that either or both could be used. This, of course, is a great advantage in case one fails. Also designers are figuring on wing surfaces that can be reefed or telescoped for better stability as well as wings that can be folded for easier transportation.
Experts do not agree on the respective merits of the two great general types of aeroplanes—that is, monoplanes and biplanes. Some claim that the monoplane is the best and others that the biplane is the most successful flier. Records show that so far monoplanes are the faster of the two types, but biplanes can be fitted with hydro-aeroplane floats, whereas it is impractical with most monoplanes. Many declare the biplane to have the greater lifting power, but the Blériot "Aero-Bus" has carried a jolly family party of eight without difficulty. Each type has its champions as to safety, reliability and endurance, but time will have to decide the question.
WRIGHT BIPLANE
First let us look at one of the latest Wright biplanes as it is brought out on the aviation field and is being tuned up by its keen-eyed young American pilot. The description of the 1909 Wright will be remembered. Also it will be remembered how the Wright brothers in 1910 discarded the forward horizontal elevating rudder entirely, and substituted in its place a single elevating rudder at the rear end of the tail, which also served to give fore and aft stability. Also in 1910 the Wright brothers added wheels to the skids that hitherto had been used for starting and alighting. Thus the old system of having the machine skidded along a rail by a falling weight, as previously described, was done away with in favour of its running over the ground on its wheels.
After noting these improvements, we will look at the general outlines of such a Wright racing machine as contested for the James Gordon Bennett Cup in 1910. The two main planes are the smallest yet used on a biplane, being only 21-1/2 feet wide from tip to tip, and only 3-1/2 feet from front to rear. Thus, the aspect ratio, it will be seen is 7. They are the same general shape as the planes on the other Wright machines, and their total area is 145 square feet. The machine is steered up or down by the horizontal elevator rudder in the rear, which is oblong-shaped, 8 by 2 feet. The rudder that steers the machine from right to left is set vertically at the tail and is worked in combination with the levers that work the warping of the tips of the planes. On this little machine the twin-screw propellers, 8-1/2 feet in diameter, sweep practically the whole width of the machine. They are connected by chains to the 60-horsepower 8-cylinder Wright engine (in ordinary biplanes of this type the engine is 30 horsepower) and make 525 revolutions per minute (in ordinary machines of this type they make 450 revolutions per minute). The machine weighs a total of 760 pounds and is capable of more than 60 miles an hour.
The elevation rudder is controlled by a lever set either at the right or left hand of the operator. The direction rudder is controlled by a lever that also controls the warping of the planes, as in turning it is necessary to cant the machine over to the inner side of the curve being made, in order to prevent slipping sidewise through the air. However the handle of the direction and warping lever is so arranged by a clutch system that by moving the lever simply from side to side the direction lever can be worked independently of the warping. The direction and balancing system then, we see, is worked in this manner. Say, while flying, a gust of wind causes the biplane to dip at the right end. The operator quickly moves his warping lever forward. This pulls down the tips of the right planes, and at the same time elevates the tips of the left planes. The change of the angle makes the right side lift to its normal position while it makes the left side drop. Consequently the machine is restored to an even keel and the operator lets the planes spring back to their normal shape.
The large 1911 Wright biplanes, model B, are designed the same as the small racing models except that the wings have a spread of 39 feet, and a depth of 6-1/4 feet—a total area of 440 square feet. The perpendicular triangular surfaces in front like two little jib sails, are a distinguishing feature, although the latest Wright models substitute narrow vertical fins about six feet tall and six inches wide. They are placed immediately in front of the main planes. The hydro-aeroplane substitutes two aluminum floats for the wheels.