The New Student's Reference Work/Aeronautics

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Aeronautics (ā-er-o-naw′tiks) or Aerial Navigation. Men have tried to navigate the air in two different ways. One of these is to construct a body whose average density is so much less than that of air that the body will rise, lifting not only itself but a considerable load besides. These bodies are known as “balloons.” The other method is to construct a body—a machine—of material much denser than air, yet supplied with energy sufficient to lift itself and to propel itself in the air. Such bodies are known as “flying machines.”

THE BALLOON

SPHERICAL BALLOON

The principle upon which balloons are constructed is that a body submerged in air, or in any other fluid, is buoyed up by force equal to the weight of the displaced air. If, now, a body can be made to weigh less than the air which it displaces, it will, of course, rise in the atmosphere when set free; and it will continue to rise until it reaches air of such a density that the weight of the body is just equal to the weight of the displaced air.

The principal bodies that have been used for this purpose are hot air, hydrogen, and coal-gas. One of these gases is confined in a large bag of oiled silk or some closely woven texture covered with varnish.

Over the bag which holds the gas is stretched a network of cords and ropes supporting beneath the balloon a light basket; and when balloons are used for scientific and military purposes the load in this basket generally includes, besides the observers, a barometer to measure the height, a thermometer to measure the temperature, a hygrometer to measure the amount of moisture in the atmosphere, a field-glass, an anchor and some sand which may be thrown overboard either in case tone is descending too rapidly, or in case one wishes to ascend higher.

A valve enables the pilot to let gas escape at will, a long drag rope facilitates landing by relieving the balloon of its weight as it reaches the ground, and a ripping strip which is torn out on landing lets out all the gas, when the balloon at once collapses and dragging is prevented.

Among the most remarkable voyages on record are the following:

June 5, 1783. The Montgolfier brothers completed and launched the first balloon ever constructed. It was about 30 feet in diameter and was filled with hot air. It remained above the ground for about ten minutes, and during this time traveled about a mile and a half. No observer ascended with the balloon. The invention of the balloon is, therefore, generally assigned to these brothers, Stephen and Joseph Montgolfier, who were paper-makers at Annonay, in Southern France, where this first ascent was made.

Oct. 15, 1783. M. François Pitâtre de Rozier ascended in a balloon, which, for the first time, carried with it a human being. This balloon was attached to the ground by ropes; but in the month following this same navigator made a trip in a free balloon.

June 21, 1859. Mr. John Wise and two companions traveled from St. Louis, Mo., to Jefferson county, New York, a distance of 1,150 miles, in 19 hours, thus accomplishing an average speed of over 60 miles an hour.

Sept. 5, 1862. Mr. James Glaisher, in England, made the highest ascent on record, reaching an altitude of 37,000 feet (seven miles). At a height of five miles Mr. Glaisher became insensible, and his companion, Mr. Coxwell, having lost the use of his limbs, was barely able to open a valve with his teeth and thus allow the balloon to descend. An extended account of this daring trip is given by Mr. Glaisher in the British Association Report for 1862.

July 11, 1897. Andrée and two companions started from Danes Island, hoping to reach the North Pole, a distance of some 600 miles. Two days later (July 13) a carrier pigeon returned with a short message of “all well,” from Lat. 82° N. Long. 15° E. From then until the present (1908) no trace of either men or balloon has been discovered.

Oct. 9, 1900. Count de la Vaulx and a companion traveled from Paris to Russia, 1,200 miles, in 35¾ hours, making the longest continuous voyage in air up to that date.

In recent years ballooning has come to be a popular sport. Aero clubs have been formed in Europe and America, and ascensions and balloon races are common. It is claimed by enthusiasts that under a skillful pilot, who will observe weather conditions as does a good sailor, ballooning is less dangerous than automobiling, while it is less expensive and far more interesting.

James Gordon Bennett in 1906 gave a cup to be contested for by balloons or other air craft. The first race was held at Paris, Sept. 30, 1906, 16 balloons, representing America, Great Britain, France, Germany and Italy, contesting. The cup was won by the balloon “United States,” piloted by Lieut. F. P. Lahm of the United States Army, which landed near Scarborough, England, after covering a distance of 415 miles.

The second race was held at St. Louis, Mo., Oct. 21, 1907. There were nine entries, representing America, England, Germany and France. The race was won by the German balloon, Pommern, piloted by Dr. Oscar Erbsloch, which landed at Asbury Park, N. J., 876¾ miles from St. Louis.

DIRIGIBLE BALLOONS

DIRIGIBLE BALLOON

M. Santos-Dumont, a Brazilian working in Paris, produced a large balloon successfully equipped with a powerful oil engine, a propellor and a rudder. By means of shifting the ballast the engine is made to drive the balloon either up or down, as well as straight ahead. This hybrid apparatus, which is known as a “dirigible,” belongs essentially to the class of balloons, and is not a true flying machine. In the summer and autumn of 1901 Santos-Dumont repeatedly encircled the Eiffel Tower in Paris. Since that date distinct progress has been made in dirigible airships of the general type of that of Santos-Dumont. The problems of producing sufficiently light and powerful motors and of securing speed, endurance and control have been so far achieved as to give to the “dirigible” a practical value which has secured for it a place in the military establishments of the leading Powers. It has been adopted by France, England and Germany, and its use is contemplated by the United States government. The French government owns four dirigible airships, all of what is known as the Lebaudy type. They are built with a gas bag about 200 feet long and 30 feet in diameter. The under side is lined with a rigid plate, which takes the place of the suspended framework of other types of airships. To the bottom piece is suspended the car, with a propeller in either side. The gas bag has side and rear fins, and a rudder in the rear. The Von Zeppelin airship, owned by the German government, is the largest of its kind, the gas bag being 420 feet long and 40 feet in diameter, with a gas capacity of between 300,000 and 400,000 cubic feet. It has attained a speed of 33 miles an hour, has made a trip of 220 miles and back, and has stayed up for seven hours.

The value of the dirigible airship is in the ability it affords to pass over an enemy’s country and observe the disposition and movements of troops and the plans and character of defenses. The Hague conference in 1907 passed a rule forbidding the dropping of projectiles from balloons or aerial machines.

FLYING MACHINES

We pass now to the third and more hopeful method of aerial navigation. The problem here is to construct a machine which shall contain within itself a supply of energy not only sufficient to lift itself above the ground but also to propel itself through the air. The ablest students of this problem have abandoned all hopes of successfully imitating the bird: the model is too complicated. Accordingly, they have concentrated their study upon driving through the air at high speed a thin, light plane, having its forward edge higher than its rear edge, and supporting beneath it the engine which propels it.

If a railway car had open sides and a plane roof, sloping from the front to the rear, it is evident that the faster the car is driven forward the greater will be the tendency to lift off the roof of the car.

Imagine, now, that the car is very light but strong, that it contains a light but powerful engine, and that the light, sloping roof is strong enough to support the entire car and its contents; you will then have in mind the type of flying machine which was constructed by Maxim in England and improved by Langley in America.

Since the experiments of Maxim and Langley, which were not practically successful, the problem has received the continuous study and effort of inventors and scientists. The first really successful result was achieved by the Wright Brothers of Dayton, Ohio, who after years of study and experiment produced an aeroplane which in 1905, near Dayton, made many successful ascensions. In 1908, at Fort Myers, near Washington, D. C., and LeMans, France, they frequently remained in the air for over an hour, changing direction and ascending and lighting at will. The machine is a biplane, the sustaining surfaces of which are parallel, one above the other, about 40 feet by 7, and is driven by a propeller placed amidships. In front is a biplane horizontal rudder for regulating the flight up or down, and in the rear a vertical rudder for steering. It is started by running on a monorail until sufficient impetus is secured to permit it to rise unaided.

Wright Brothers Aeroplane
R, rudder; LR, lifting and lowering rudder; P P, propellers.

Since 1908 marked advance has been made in perfecting the construction of the aeroplane and in actual performances. In 1909 Orville Wright by a cross-country flight, carrying a passenger, met the last government test, and the Wright aeroplane was accepted for use of the signal corps of the army. They received $25,000 with a bonus of $5,000 for speed attained beyond 40 miles an hour. (See Wright, Wilbur.)

The most important step in connection with aviation after the invention of the Wright Brothers, was the grant of an American patent in 1913 for a stabilizer of their invention for maintaining automatic control. To prevent the tipping of the wings by a sudden puff a pendulum is connected with a motor; while to prevent sudden swerving up or down, there is a horizontal rudder actuated by a small plane mounted at a different angle from the main aeroplane, so that whenever there is a sudden change in the position of the machine, the horizontal rudder is adjusted so as to restore it to the proper position, very much as a bird governs similar motions with its tail.

An interesting development of aeronautics is the hydroaeroplane which combines a flying machine with a boat. It skims through the water and lifts when the proper speed is reached.

Wright in flight in his aeroplane Zeppelin Dirigible III
Bleriot monoplane
Curtiss and his biplane