Australian Flight finish, 10th December, 1919.
The crew and machine.
Cape to Cairo.
The ‘Silver Queen’ and its crew.
Early in 1920 came a series of attempts at completing the journey by air between Cairo and the Cape. Out of four competitors Colonel Van Ryneveld came nearest to making the journey successfully, 长沙桑拿论坛体验 leaving England on a standard Vickers-Vimy bomber with Rolls-Royce engines,
identical in design with the machine used by Captain Ross-Smith on the England to Australia flight. A second Vickers-Vimy was financed by the Times newspaper and a third flight was undertaken with a Handley-Page machine under the auspices of the Daily Telegraph. The Air Ministry had already prepared the route by means of three survey parties which cleared the aerodromes and landing grounds,271 dividing their journey into stages of 200 miles or less. Not one of the competitors completed the course, but in both this and Ross-Smith’s flight valuable data was gained in respect of reliability of machines and engines, together with a mass of meteorological information.
The Handley-Page Company announced in the early months of 1920 that they had perfected a new design of wing which brought about a twenty to forty per cent improvement in lift rate in the year. When the nature of the design was made public, it was seen to consist of a division of the wing into small sections, each with its separate lift. A few days later, Fokker, the Dutch inventor, announced the construction of a machine in which all external bracing wires are obviated, the wings being of a very deep section and self-supporting. The value of these two inventions remains to be seen so far as commercial flying is concerned.
The value of air work in war, especially so far as the Colonial campaigns in which British troops are constantly being engaged is in question, was very thoroughly demonstrated in a report issued early in 1920 with reference to the successful termination of the Somaliland campaign through the intervention of the Royal Air Force, which between January 21st and the 31st practically destroyed the Dervish force under the Mullah, which had been a thorn in the side of Britain since 1907. Bombs and machine-guns did the work, destroying fortifications and bringing about the surrender of all the Mullah’s following, with the exception of about seventy who made their escape.
Certain records both in construction and performance had characterised the post-war years, though as design advances and comes nearer to perfection, it is obvious272 that records must get fewer and farther between. The record aeroplane as regards size at the time of its construction was the Tarrant triplane, which made its first—and last—flight on May 28th, 1919. The total loaded weight was 30 tons, and the machine was fitted with six 400 horse-power engines; almost immediately after the trial flight began, the machine pitched forward on its nose and was wrecked, causing fatal injuries to Captains Dunn and Rawlings, who were aboard the machine. A second accident of similar character was that which befell the giant seaplane known as the Felixstowe Fury, in a trial flight. This latter machine was intended to be flown to Australia, but was crashed over the water.
On May 4th, 1920, a British record for flight duration and useful load was established by a commercial type Handley-Page biplane, which, carrying a load of 3,690 lbs., rose to a height of 13,999 feet and remained in the air for 1 hour 20 minutes. On May 27th the French pilot, Fronval, flying at Villacoublay in a Morane-Saulnier type of biplane with Le Rhone motor, put up an extraordinary type of record by looping the loop 962 times in 3 hours 52 minutes 10 seconds. Another record of the year of similar nature was that of two French fliers, Boussotrot and Bernard, who achieved a continuous flight of 24 hours 19 minutes 7 seconds, beating the pre-war record of 21 hours 48? seconds set up by the German pilot, Landemann. Both these records are likely to stand, being in the nature of freaks, which demonstrate little beyond the reliability of the machine and the capacity for endurance on the part of its pilots.
Trial Flight of the Tarrant Triplane at Farnborough.
The machine before the crash.
Meanwhile, on February 14th, Lieuts. Masiero and Ferrarin left Rome on S.V.A. Ansaldo V. machines273 fitted with 220 horse-power S.V.A. motors. On May 30th they arrived at Tokio, having flown by way of Bagdad, Karachi, Canton, Pekin, and Osaka. Several other competitors started, two of whom were shot down by Arabs in Mesopotamia.
Considered in a general way, the first two years after the termination of the Great European War form a period of transition in which the commercial type of aeroplane was gradually evolved from the fighting machine which was perfected in the four preceding years. There was about this period no sense of finality, but it was as experimental, in its own way, as were the years of progressing design which preceded the war period. Such commercial schemes as were inaugurated call for no more note than has been given here; they have been experimental, and, with the possible exception of the United States Government mail service, have not been planned and executed on a sufficiently large scale to furnish reliable data on which to forecast the prospects of commercial aviation. And there is a school rapidly growing up which asserts that the day of aeroplanes is nearly over. The construction of the giant airships of to-day and the successful return flight of R34 across the Atlantic seem to point to the eventual triumph, in spite of its disadvantages, of the dirigible airship.
This is a hard saying for such of the aeroplane industry as survived the War period and consolidated itself, and it is but the saying of a section which bases its belief on the fact that, as was noted in the very early years of the century, the aeroplane is primarily a war machine. Moreover, the experience of the War period tended to discredit the dirigible, since, before the introduction of helium gas, the inflammability of its274 buoyant factor placed it at an immense disadvantage beside the machine dependent on the atmosphere itself for its lift.
As life runs to-day, it is a long time since Kipling wrote his story of the airways of a future world and thrust out a prophecy that the bulk of the world’s air traffic would be carried by gas-bag vessels. If the school which inclines to belief in the dirigible is right in its belief, as it well may be, then the foresight was uncannily correct, not only in the matter of the main assumption, but in the detail with which the writer embroidered it.
On the constructional side, the history of the aeroplane is still so much in the making that any attempt at a critical history would be unwise, and it is possible only to record fact, leaving it to the future for judgment to be passed. But, in a general way, criticism may be advanced with regard to the place that aeronautics takes in civilisation. In the past hundred years, the world has made miraculously rapid strides materially, but moral development has not kept abreast. Conception of the responsibilities of humanity remains virtually in a position of a hundred years ago; given a higher conception of life and its responsibilities, the aeroplane becomes the crowning achievement of that long series which James Watt inaugurated, the last step in inter-communication, the chain with which all nations are bound in a growing prosperity, surely based on moral wellbeing. Without such conception of the duties as well as the rights of life, this last achievement of science may yet prove the weapon that shall end civilisation as men know it to-day, and bring this ultra-material age to a phase of ruin on which saner people can build a world more reasonable and less given to groping after purely material advancement.
The Tarrant smash.
Front view of crashed machine. Searching for the injured after the smash.
Part II 1903–1920: PROGRESS IN DESIGN I THE BEGINNINGS
Although the first actual flight of an aeroplane was made by the Wrights on December 17th, 1903, it is necessary, in considering the progress of design between that period and the present day, to go back to the earlier days of their experiments with ‘gliders,’ which show the alterations in design made by them in their step-by-step progress to a flying machine proper, and give a clear idea of the stage at which they had arrived in the art of aeroplane design at the time of their first flights.
They started by carefully surveying the work of previous experimenters, such as Lilienthal and Chanute, and from the lesson of some of the failures of these pioneers evolved certain new principles which were embodied in their first glider, built in 1900. In the first place, instead of relying upon the shifting of the operator’s body to obtain balance, which had proved too slow to be reliable, they fitted in front of the main supporting surfaces what we now call an ‘elevator,’ which could be flexed, to control the longitudinal balance, from where the operator lay prone upon the main supporting surfaces. The second main innovation which they incorporated in this first glider, and the principle of which is still used in every aeroplane in existence, was the attainment of lateral balance by warping the extremities of the main planes. The278 effect of warping or pulling down the extremity of the wing on one side was to increase its lift and so cause that side to rise. In the first two gliders this control was also used for steering to right and left. Both these methods of control were novel for other than model work, as previous experimenters, such as Lilienthal and Pilcher, had relied entirely upon moving the legs or shifting the position of the body to control the longitudinal and lateral motions of their gliders. For the main supporting surfaces of the glider the biplane system of Chanute’s gliders was adopted with certain modifications, while the curve of the wings was founded upon the calculations of Lilienthal as to wind pressure and consequent lift of the plane.
This first glider was tested on the Kill Devil Hill sandhills in North Carolina in the summer of 1900, and proved at any rate the correctness of the principles of the front elevator and warping wings, though its designers were puzzled by the fact that the lift was less than they expected; whilst the ‘drag’ (as we call it), or resistance, was also considerably lower than their predictions. The 1901 machine was, in consequence, nearly doubled in area—the lifting surface being increased from 165 to 308 square feet—the first trial taking place on July 27th, 1901, again at Kill Devil Hill. It immediately appeared that something was wrong, as the machine dived straight to the ground, and it was only after the operator’s position had been moved nearly a foot back from what had been calculated as the correct position that the machine would glide—and even then the elevator had to be used far more strongly than in the previous year’s glider. After a good deal of thought the apparent solution of the trouble was finally found.279 This consisted in the fact that with curved surfaces, while at large angles the centre of pressure moves forward as the angle decreases, when a certain limit of angle is reached it travels suddenly backwards and causes the machine to dive. The Wrights had known of this tendency from Lilienthal’s researches, but had imagined that the phenomenon would disappear if they used a fairly lightly cambered—or curved—surface with a very abrupt curve at the front. Having discovered what appeared to be the cause they surmounted the difficulty by ‘trussing down’ the camber of the wings, with the result that they at once got back to the old conditions of the previous year and could control the machine readily with small movements of the elevator, even being able to follow undulations in the ground. They still found, however, that the lift was not as great as it should have been; while the drag remained, as in the previous glider, surprisingly small. This threw doubt on previous figures as to wind resistance and pressure on curved surfaces; but at the same time confirmed (and this was a most important result) Lilienthal’s previously questioned theory that at small angles the pressure on a curved surface instead of being normal, or at right angles to, the chord is in fact inclined in front of the perpendicular. The result of this is that the pressure actually tends to draw the machine forward into the wind—hence the small amount of drag, which had puzzled Wilbur and Orville Wright.
Another lesson which was learnt from these first two years of experiment, was that where, as in a biplane, two surfaces are superposed one above the other, each of them has somewhat less lift than it would have if used alone. The experimenters were also still in doubt280 as to the efficiency of the warping method of controlling the lateral balance as it gave rise to certain phenomena which puzzled them, the machine turning towards the wing having the greater angle, which seemed also to touch the ground first, contrary to their expectations. Accordingly, on returning to Dayton towards the end of 1901, they set themselves to solve the various problems which had appeared and started on a lengthy series of experiments to check the previous figures as to wind resistance and lift of curved surfaces, besides setting themselves to grapple with the difficulty of lateral control. They accordingly constructed for themselves at their home in Dayton a wind tunnel 16 inches square by 6 feet long in which they measured the lift and ‘drag’ of more than two hundred miniature wings. In the course of these tests they for the first time produced comparative results of the lift of oblong and square surfaces, with the result that they re-discovered the importance of ‘aspect ratio’—the ratio of length to breadth of planes. As a result, in the next year’s glider the aspect ration of the wings was increased from the three to one of the earliest model to about six to one, which is approximately the same as that used in the machines of to-day. Further than that, they discussed the question of lateral stability, and came to the conclusion that the cause of the trouble was that the effect of warping down one wing was to increase the resistance of, and consequently 长沙桑拿洗浴论坛交流 slow down, that wing to such an extent that its lift was reduced sufficiently to wipe out the anticipated increase in lift resulting from the warping. From this they deduced that if the speed of the warped wing could be controlled the advantage of increasing the angle by warping could be utilised as they originally281 intended. They therefore decided to fit a vertical fin at the rear which, if the machine attempted to turn, would be exposed more and more to the wind and so stop the turning motion by offering increased resistance.
As a result of this laboratory research work the third Wright glider, which was taken to Kill Devil Hill in September, 1902, was far more efficient aerodynamically than either of its two predecessors, and was fitted with a fixed vertical fin at the rear in addition to the movable elevator in 长沙桑拿会所哪里最好 front. According to Mr Griffith Brewer,8 this third glider contained 305 square feet of surface; though there may possibly be a mistake here, as he states9 the surface of the previous year’s glider to have been only 290 square feet, whereas Wilbur Wright himself10 states it to have been 308 square feet. The matter is not, perhaps, save historically, of much importance, except that the gliders are believed to have been progressively larger, and therefore if we accept Wilbur Wright’s own figure of the surface of the second glider, the third must have had a greater area than that given by Mr Griffith Brewer. Unfortunately, no evidence of the Wright Brothers themselves on this point is available.
The first glide of the 1902 season was made on September 17th of that year, and the new machine at once showed itself an improvement on its predecessors, though subsequent trials showed 长沙桑拿交流论坛 that the difficulty of lateral balance had not been entirely overcome. It was decided, therefore, to turn the vertical fin at the rear into a rudder by making it movable. At the same time it was realised282 that there was a definite relation between lateral balance and directional control, and the rudder controls and wing-warping wires were accordingly connected. This ended the pioneer gliding experiments of Wilbur and Orville Wright—though further glides were made in subsequent years—as the following year, 1903, saw the first power-driven machine leave the ground.