Flying Machines Heavier than Air—The Flapping Machine—The Soaring or Gliding Machine—How Man has beaten the Birds— The Ever-increasing Uses of the Aeroplane.
FROM earliest times nothing was more familiar to man than the flight of birds, and all his earlier efforts to fly were attempts to copy birds. The "ornithopter" was his first flying machine. This was made with flapping wings, and we read of men making wings and trying to use them throughout the Middle Ages. But a bird’s bones are hollow, and its weight extraordinarily small for its size, while its muscles are, comparatively speaking, enormously more powerful than those of a man, so it is not surprising that most of the earlier experimenters failed to rise from the ground, or, if they started from a height, broke themselves up.
In 1809 an Englishman named Degen constructed a machine with deeply concave wings which were covered with taffeta bands arranged like the feathers of a bird’s wings. With these he is said to have risen to a height of fifty-four feet, but the fact is that his apparatus lifted only seventy out of the one hundred and sixty pounds of the weight of the operator and his machine, the other ninety pounds being balanced by a counterweight attached to a rope passing over a pulley. So what Degen’s invention really proved was man’s inability to fly by means of his own muscles. Next came an ingenious flying machine invented by a Frenchman named Trouvé. It was worked by a U-shaped Bourdon tube, the tendency of which is to flatten out when subjected to sudden internal pressure. This pressure Trouvé obtained by firing cartridges inside the tube. The machine (it was only a small model) did actually fly for a distance of nearly a hundred yards. The tube, flattening out at each explosion, worked a pair of wings which flapped like those of a bird.
In the early eighties of the last century, Hargrave, an Australian, began a series of experiments with box kites, and went on to build little flying machines driven successively by clockwork, rubber bands, compressed air, and steam. In the last of these machines the wings flapped at a speed of 342 strokes to the minute, and the total weight of the whole thing, including twenty-one ounces of fuel and water, was only seven pounds. The wings were thirty-six inches long and from four to nine inches wide. The lightness of Hargrave’s power plant has never been surpassed except by the latest gasoline engines, and his model flew for a distance of several hundred feet.
A number of experiments were also made during the nineteenth century with what are called "helicopters"— that is, machines made to rise straight into the air by the drive of a wide-winged propeller. It is interesting to note that the wonderful Italian artist and inventor, Leonardo da Vinci, who was born in 1452, made a plan for a helicopter to be built of iron and bamboo framing, but dropped the idea because he had no power suitable for driving the screw. Several of the model helicopters made during the nineteenth century were capable of flight. In 1870 Penaud invented one driven by a rubber band, which had quite a run as a popular toy, for it would rise to the ceiling of a lofty room with the greatest ease. Edison, Renard, and Maxim have all done much work on helicopters; and Mr. Louis Brennan, inventor of the Brennan torpedo, is busy on similar researches, and at the time of writing has, I understand, constructed a helicopter which will lift a considerable weight. But the helicopter, to be useful, must not only be able to rise; it must also fly like an aeroplane. This will probably be achieved in the near future.
The aeroplane was the first successful type of flying machine. As the ornithopter was modeled after the flapping flight of birds, so the aeroplane has been designed to imitate their soaring flight. As we all know, birds that soar, such as the hawks, eagles, and vultures, are much
the strongest fliers, and habitually fly at a height greater than that attained by the birds that merely flap their wings.
Asked who invented the modern aeroplane, your answer would, no doubt, be the two brothers Orville and Wilbur Wright; but without in the least detracting from the wonderful work done by these two brilliant Americans, the fact is that the real pioneer of aeroplane flight was Clement Ader. So long ago as 1872 this inventor was busy with flapping machines, but, finding them useless, in 1890 he built a real aeroplane with funds furnished by the French Government. Its wings had a fifty-four-foot span, and the machine was drawn through the air by two four-bladed screws driven by a steam engine of about thirty horsepower. Ader’s experiments cost more than twenty thousand pounds, and the result was that when first tried in October, 1891, the machine rose and flew for a distance of 164 feet. Seven years later, at Satory in France, Ader’s machine made a semicurcular flight of nearly a thousand feet. But Ader had not succeeded in getting a proper balance, and both his machines were wrecked for this reason. At the same time Professor S. P. Langley was making his interesting experiments in America, and was working on the lines along which more recent inventors have reached success. Langley built several flying machines, beautiful little models which he endeavored to launch from the top of a house boat anchored in the Potomac River. His engines, driven by steam, were triumphs of strength and lightness. After many failures, on May 6, 1896, one of these models did fly for more than a quarter of a mile. This, mind you, was a very wonderful feat, for the machine was of considerable size, yet did not run along the ground, but had to take off instantly from a height of a few feet above the water. Its pace was nearly twenty-five miles an hour, and when steam gave out it settled quite quietly on the water.
Langley was on the right track, but the trouble was that people at large would not take him seriously. Even thirty years ago anyone who experimented with flying machines was looked upon as a lunatic.
Langley, however, who was President of the Smithsonian Institution, did eventually obtain a grant from the United States Government, and built a man-carrying machine weighing 830 pounds and provided with a gasoline engine of fifty-two horsepower. If only Langley had realized that such a machine required a run to launch it, I verily believe that he, and not the Wrights, would have been recognized as the pioneer of flying. But on each occasion that he tried it, the attempt was made to launch it from the top of a house boat, and on each occasion it failed to get up the necessary speed and so plunged into the river. Ridicule was heaped upon Langley, and he died, some say, of a broken heart. Fifteen years after this unsuccessful experiment, that is, in May, 1914, Mr. Glenn Curtiss, the well-known American aviator, got Langley’s machine out of the museum where it was kept, fitted it with wheels, and made a successful flight with it at Bath in New York State.
In the nineties a number of experimenters were at work upon gliders. First, Octave Chanute, then the two Lilienthals, and also Percy Pilcher. Gustav Lilienthal and Pilcher were both killed in the course of their experiments, but the work they did proved of immense value to those who came after them.
In the Scientific American for May 20, 1905, it is stated: "An aeroplane has been constructed that in all circumstances will retain its equilibrium, and is subject in its gliding flight to the control and guidance of an operator." This machine, constructed by Professor John J. Montgomery, was, however, not an aeroplane but a glider, and it was given its first public trial at Santa Clara, in California, on April 29, 1905. It was sent up in an ordinary hot-air balloon, and at the height of about four thousand feet it was cut loose. Its pilot was Daniel Moloney, a well-known parachute jumper. The thousands who watched from the ground saw Moloney glide downward, making the most extraordinary and complex evolutions. He circled, did figure-of-eight turns and the most hairraising dives. At times his speed was estimated at nearly seventy miles an hour, yet after a flight of about eight miles he brought the machine to rest upon a spot previously marked out, and so lightly that, although compelled to land upon his feet, he was not even jarred. Octave Chanute saw the flight and so did Alexander Graham Bell, and the latter said positively that all subsequent attempts in aviation must begin with the Montgomery machine. So great was the stability of Montgomery’s glider that, on one occasion, Moloney, when in the air, made a side-somersault. Yet the machine righted itself and continued on its regular course.
We come now to the Wright brothers. The Wrights began by reading everything they could find on the work of previous experimenters, and their first glider was a modification of Chanute’s biplane glider. They both, however, believed more in practice than in theory, and, choosing a lonely place among the sandhills of the coast of North Carolina, set to work to make experiments in gliding. For many months they were out on every possible
day, making hundreds and hundreds of gliding flights from the summits of the taller dunes. They began work in 1896, but it was not until 1903 that they first fitted a motor into one of their machines. On a dull winter morning, December 17, 1903, they launched their motor-driven glider, and with it made four flights, the longest being 852 feet. This distance was not so great as the flight of Langley’s model in 1896, nor as that covered by Ader in 1897. But it was the first time that a power-driven machine had carried a man into the air and had landed safely without accident of any sort.
All through 1904 the Wrights continued their experiments and increased the length of their flights to 1377 feet. It was in 1905 that real success crowned their efforts, for in September of that year they flew a distance of twelve miles in eighteen minutes at Dayton, Ohio, and before the end of the year had increased this to no less than twenty-four miles.
Meantime, others were at work in France, among them Gabriel Voisin, who designed the box-kite type of machine on which Farman and Delagrange made their first flights. But it must not be forgotten that it was Santos-Dumont who made the first European flight in a heavier-than-air machine. That was on August 22, 1906. True, it was only 220 yards, but the machine ran on wheels, rose like a modern ‘plane, and came down safely, and this constituted a record.
Farman’s first flights, made in 1907, were very short, but in October of that year he covered 440 yards in one flight at a speed of 33.7 miles an hour. A prize of £2000 was then offered for a circular flight of one kilometre, and on the following January 13 this was won by Farman.
Farman’s machine was a biplane. The next great success was won by M. Blériot on a monoplane. He crashed again and again, but always escaped serious injury. You must remember that these early flights were, as a rule, made at a height of only a very few feet from the ground.
By 1908 distances of ten and twelve miles had been covered, and in 1909 the Wrights opened their first flying school. In the early summer of 1909 Blériot flew from Etampes to Orleans, a distance of twenty-five miles, skimming low over houses and trees and keeping pace for a time with the Paris-Orleans express, the windows of which were crowded with amazed faces. Then, on July 25, Blériot, rising in a slight mist from the French side of the Channel, flew to England, and so achieved the most memorable feat in all the story of aviation up to that time. The distance he covered was twenty-seven miles and the time taken forty-three minutes. He attained a height above the sea of three hundred feet, and, although he landed with rather a bad bump, breaking his propeller, yet he himself escaped injury.
Since that date the progress of the aeroplane has been steady and swift, so that in 1924 Farman’s speed of forty miles an hour has been increased to 240 miles, or four miles a minute. This feat was achieved by Adjutant Bonnet at Istres in France on November 7, 1924. The largest aeroplanes are enormous in size. The Barling bomber weighs nearly twenty tons as against the 750 pounds of the Wrights’ first machine, and has engines of nearly three thousand horsepower. It carries pilot, observer, two or three mechanics, two thousand gallons of fuel, and five thousand pounds’ weight of bombs. The wings of a giant monoplane used for carrying passengers in Germany are so long that sixty men can stand upon them at one time. The modern aeroplane flies at an average height of about a mile, but ‘planes have climbed to nearly seven miles above the earth, where a temperature of sixty-nine degrees below zero was experienced. As for distance records, the Atlantic has been flown; but since that date an airman has flown right across the American continent from Jacksonville, Florida, to San Diego, California, a distance of 2775 miles, with only one stop. In July, 1924, an aeroplane remained in the air for no less than thirty-eight hours. The heroes of this exploit were two French pilots, Coupet and Drouhin.
In 1925 the first "around-the-world" flight was made by six American aviators in three specially built American planes. A fourth plane started but met with an accident and was unable to complete the trip, which started and ended at Seattle. The distance covered was 26,345 miles at an average rate of seventy-two and one half miles an hour, while the flying time was fifteen days, three hours and seven minutes.
The early machines were flimsy things of wood and canvas, but to-day metal is being more and more used. Professor Hugo Junkers, the German designer, has plans for a huge all-metal seaplane, with a hull one hundred feet long and four engines, each of a thousand horsepower. The single all-metal wing is 260 feet from tip to tip, and the machine will run not on expensive gasoline but upon crude oil. The total weight of this giant seaplane is nearly fifty tons.
The aeroplane is now rivaling the motor car and train for the conveyance of passengers and mails. So long ago as 1920, nearly five thousand passengers were carried between England and the Continent in a twelvemonth, and the number is increasing year by year. New aerodromes are being constructed everywhere, also aerial lighthouses, and all the big passenger machines are fitted with wireless, by means of which the pilot can be kept informed as to sudden changes in weather.
Quite apart from its use as a carrying machine in peace or in war, every year finds new uses for the aeroplane. For instance, ‘planes are used in "spotting" for fishing fleets. Shoals of herring, mackerel, and pilchards can be easily seen from the air when quite invisible from the shore or boats. In similar fashion, aeroplanes spot the seal herds on the ice off Newfoundland, thus enabling the fleet to sail at once for the scene of action, instead of wasting time searching for the animals. There are swampy districts in Alsace and Lorraine, where the anopheles mosquito spreads malaria. The French sanitary authorities have used aeroplanes to spray oil on the marshes, and so destroy these deadly insects. In the spring of 1920, when the town of Port Deposit in Maryland was threatened with destruction from flood water piling up behind ice barriers on the Susquehanna River, army airmen dropped large charges of explosive upon the ice barriers, smashed them to atoms, and released the pent-up stream.
But what is, perhaps, the strangest use to which the flying machine has yet been put is to combat the plant disease known as blackstem rust, which every year destroys two hundred million bushels of North American wheat. The rust spores are so small that they are invisible to the naked eye, and it is therefore most difficult to trace the path they travel as they are blown on the winds. Observers employed by the United States Department of Agriculture have overcome this difficulty by using aeroplanes. Small oil-smeared glass plates are exposed as the ‘plane flies across country, and microscopic examination at the end of the journey reveals to the experts the direction of the dreaded enemy’s advance.
The aeroplane was made possible by the invention of an engine of enormous power which at the same time was light and compact. The improvement of these essential features has been the constant aim of all inventors during recent years, and it is difficult to imagine anything more simple than the ten-cylinder engine shown in the accompanying illustration. It was exhibited in Paris on the eve of the War, and was capable of developing one hundred horsepower.