“The human bird shall take his first flight, filling the world with amazement, all writings with his fame, and bringing eternal glory to the nest whence he sprang.” - LEONARDO DA VINCI.
THE network of airways now covering the world, and running with rare exceptions to a strict time schedule. the large number of hours flown regularly in private machines, the experiments in stratosphere flying, and similar examples of aeronautical develop-ment are a testimony not only to human achievement but also to imagination.
It would be difficult to accept a challenge to state exactly when the thought of human flight was first conceived. It began, no doubt, before permanent record of it was possible; as soon, in fact, as man became restless and aspired to a larger and freer experience. How soon that was no historian can tell with certitude. Yet there are certain landmarks (or perhaps one should say airmarks) which, apart from mere fancy, go to prove that the possibility of flight in accordance with natural mechanical laws was established far earlier than is commonly supposed.
THIS GLIDER, built by Otto Lilienthal in 1895, had a span of 18 feet and a total area of 200 square feet. An earlier glider, built by Lilienthal in 1891, first established the superiority of the cambered plane in flight. It weighed 40 lb, and had a supporting surface of about 107 square feet. Lilienthal made many successful glides from a hill at Gross Lichterfelde, near Berlin.
It is natural to think easily of the Wright brothers and their first sustained flight, and of Louis Bleriot’s first aeroplane journey from France to England in 1909. To travel on wings from one country to another caught the imagination because it established a dramatic change in international relationships, a change that might have grave or happy consequences. But, rejecting legend as we must, and ignoring the kite of pre-Christian age, we can go back as far as the fifteenth century to find that Leonardo da Vinci recorded some rational principles of human flight, and showed the necessity of investigating the effect of air upon moving plane surfaces. He laid down the principles of the parachute and the helicopter, and appreciated the importance of the curvature of a bird wing in gliding and soaring flight. To him may be attributed a thoroughly scientific attitude of mind towards what had hitherto been mainly a poetic hope.
Accompanying the dream and fanciful speculation there was always the greatest of stimulants - opposition. There are records of experiment during the past few centuries, humorous and tragic and successful. Even the more practical attempts aroused scorn and derision. Aerial progress has been a long chapter illustrating both human courage and human frailty. Of some of the pioneers only the scrappiest of records survive. There was one inventor who made for himself feathered wings and jumped from a high wall, only to drop like a falling stone. His reward was to hear his wife call to him “Thee forgot, to wag, William, thee forgot to wag!” That is all we can learn of him from musty records, but he was none the less an aspirant to eternal glory, and none the less desired to fill the world with amazement, as da Vinci had forecast.
Experiment, too, was not concerned solely with heavier-than-air machines. The balloon and the flying ship (airship) intrigued the mind, and on January 7, 1785, Blanchard and Jeffries crossed in a balloon from Dover, on the English coast, to the forest of Guines, not far from Ardres, France. Two years earlier the brothers Montgolfier had sent up their hot-air balloon, first with no passengers, and later with a rooster. a sheep and a duck in a suspended cage. The inventors took no chances until the following year (1784), when Joseph Montgolfier ascended at, Lyons with six companions, including the Prince de Ligne. Madame Blanchard, too, was an enthusiast and had made some notable ascents before she met her death in 1819, when the supporting gas caught alight. She fell from the balloon on to the roof of a house and from there tumbled into the street.
STRINGFELLOW’S MODEL TRIPLANE (of which this is a replica), when it was suspended from a wire, rose and showed an obvious tendency to support itself. The model was in the Aeronautical Exhibition at the Crystal Palace, London, in 1868. Twenty years earlier Stringfellow had built the first model aeroplane - a monoplane - to fly under its own power.
There is a long list of balloon pioneers as well as of “heavier-than-air” pioneers. Running through either class is the thread of persistence and courageous experiment; but in a chapter such as this it is impossible to refer to more than a few of the significant. Sir George Cayley, for example, has been described as the Father of British Aeronautics. He was more than that, for in the first half of the nineteenth century he made the most important contributions to the science. He defined the problem of mechanical flight in this way: “To make a surface support a given weight by the application of power to the resistance of air.” In doing this he established himself as a clear thinker and a pioneer of the heavier-than-air machine; but many of his conclusions were disregarded by his successors, who thereby wasted a good deal of their time in unnecessary experiment.
Contemporaneous with Cayley was Thomas Walker, who toyed with the idea of wing-flapping flight, as it is even now being toyed with, and although he published a treatise on the subject in 1810 his conclusions proved of little worth apart from their being an encouragement to others to inquire more deeply into the general problem. It is to Cayley to whom the science early owed so much. It was Cayley who was the main inspiration to his successors.
Both Henson’s and Stringfellow’s work showed surprisingly modern tendencies. It was left to Stringfellow to continue the experiments, Henson having spent much money and having emigrated to America, where all sight of him was lost.
MODEL OF EXPERIMENTAL AEROPLANE built by Sir Hiram Maxim in 1894. It was tested on a rail track, the actual rise from which was limited to a few inches by guard rails. In these conditions its measured lift reached 10,000 lb. The wing span was 104 feet and the length 120 feet.
In 1848 Stringfellow built the first model aeroplane (a monoplane) to fly under its own power. Steam was the motive force, and flights of over forty yards were attained with, on one occasion, a rise of 1 in 7 during night. Stringfellow’s work was concluded with the making of a model triplane. Many dozen names might be listed, among them Gerard, Degen, Launoy, Le Bris, Kaufmann, Forlanini, Wenham and others not forgetting, Maxim; names that would reveal how internationally widespread was the ambition to fly. The ambition was common to all types of men and women, some of them only dreamers and poets, others more practical in their application; and still others who combined the two qualities. Of these pioneers some are known, others are lost in the mists of time.
In Great Britain the Aeronautical Society (now the Royal Aeronautical Society) was founded in 1866, and much valuable work was done by this organization in the collating of data and the spreading of useful knowledge. In France Alphonse Penaud was estimating that a power-plant of 20 to 30 hp could propel a machine of 2,600 lb total loaded weight through the air at 60 miles an hour. Lawrence Hargrave was experimenting in Australia and was building man-lifting kites. He was the pioneer of the box-kite. Samuel Pierpont Langley, the American physicist, built his experimental flying machine in 1903. In the same year, on December 17, 1903, at Kitty Hawk, North Carolina, USA, Orville Wright made the first flight on a power-driven, man-carrying biplane which he and his brother Wilbur had built. From that day the aeroplane has not looked back. The achievement of that day was made possible by the many pioneers who had experimented on various contraptions that came under the general heading of gliders.
GLIDER, built in America by Octave Chanute in collaboration with A M Herring, one of Lilienthal’s pupils. This glider, built between 1895 and 1900, was a simple biplane, but was developed from a mulitplane with wing tips which could warp when struck by gusts of wind.
CONTROLLED CHIEFLY BY THE MOVEMENTS OF THE PILOT’S BODY, the Hawk, a glider (left), was built by Pilcher in 1896 at Eynsford, Kent. Two wheels, suspended on springs, were fitted to the undercarriage. The supporting area was 170 square feet for a weight of about 50 lb.
LANGLEY’S EXPERIMENTAL FLYING MACHINE (left) was built about 1903. It was a tubular structure carrying planes arranged in pairs as a tandem monoplane, the propelling plant being mounted between the planes.
Soaring flight, although questioned by some authorities as having little more value than that of an agreeable hobby, is now practised the world over. In 1891 Otto Lilienthal built his first glider, weighing 40 lb, with a supporting surface of about 107 square feet. Two years later he made successful glides from a hill at Gross Lichterfelde, near Berlin, with a glider weighing 44 lb and of about 150 square feet total area. (The weight of an Empire flying boat, fully loaded, is 40,500 lb; its plane surface area 1,500 square feet.) Sometimes he found himself lifted higher than the launching point and this induced him to glide from hills 250 feet high near Stollen, where frequently he controlled his biplane glider for distances up to nearly 800 feet from point to point. At first he balanced his machine entirely with his body, but later he adopted a horizontal rudder operated by a line attached to his head. He was killed while experimenting with this type of control. First to establish the superiority of the cambered plane in flight, he takes a high place in our annals.
THE FIRST POWER-DRIVEN FLIGHT was made by Orville Wright on December 17, 1903, at Kitty Hawk North Carolina, USA. This historic biplane was controlled by an elevator plane in front and by a vertical rudder at the rear. The first flight lasted for twelve seconds in a wind of about 11 miles an hour. On the fourth flight a distance of 852 feet was covered.
Lilienthal undoubtedly inspired Percy S. Pilcher, an engineer and lecturer at Glasgow University, who made many glides from a hill on the banks of the Clyde and also in Germany, where he flew his chief contemporary’s biplane glider. His contribution to aerial progress was the fixing of a landing chassis to his gliders and the use of the dihedral angle, the wing tips being 4 feet above the central body. The possibility of fixing an engine to his craft attracted him, and one was under construction when he, too, met with a fatal accident. The tail of his machine collapsed during a flight near Rugby, Warwickshire.
THE ORIGINAL WRIGHT BI-PLANE was fitted with an 8-12 horse-power engine built by the Wright brothers. The aeroplane had a span of 40 ft 4 in and a length of 21 feet. Lateral stability was maintained by warping the wings, and the pilot adopted a prone position to reduce resistance.
An odd sidelight on the development of flight is the fact that elderly men have often been fascinated by it. Octave Chanute, when over sixty years of age, built a series of gliders in America. He evolved a machine which was the forerunner of many others yet to be built by other investigators. A. M. Herring, one of Lilienthal’s former pupils, piloted the Chanute gliders with considerable success, and it may be said that together they evolved the beginnings of mechanical control.
To such men, power-controlled aeroplane flight owes much. They paved the way for the Wrights themselves, for Horatio Phillips, Clement Ader, Wilhelm Kress and many others who, with greater or lesser success, were destined to be concerned with powered flight.