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开心网 五月色婷婷 开心网宝贝五月王老撸

时间: 2019年12月10日 16:20

鈥淢onsieur,鈥?she said, 鈥渃an you direct me to the Rue Maugrabine?鈥? � A simple chord of Beethoven "Did you ever hear a pain?" These comments are taken from a lecture delivered by Wilbur Wright before the Western Society of Engineers in September of 1901, under the presidency of Octave Chanute. In that lecture Wilbur detailed the way in which he and his brother came to interest themselves in aeronautical problems and constructed their first glider. He speaks of his own notice of the death of Lilienthal in 1896, and of the way in which150 this fatality roused him to an active interest in aeronautical problems, which was stimulated by reading Professor Marey鈥檚 Animal Mechanism, not for the first time. 鈥楩rom this I was led to read more modern works, and as my brother soon became equally interested with myself, we soon passed from the reading to the thinking, and finally to the working stage. It seemed to us that the main reason why the problem had remained so long unsolved was that no one had been able to obtain any adequate practice. We figured that Lilienthal in five years of time had spent only about five hours in actual gliding through the air. The wonder was not that he had done so little, but that he had accomplished so much. It would not be considered at all safe for a bicycle rider to attempt to ride through a crowded city street after only five hours鈥?practice, spread out in bits of ten seconds each over a period of five years; yet Lilienthal with this brief practice was remarkably successful in meeting the fluctuations and eddies of wind-gusts. We thought that if some method could be found by which it would be possible to practise by the hour instead of by the second there would be hope of advancing the solution of a very difficult problem. It seemed feasible to do this by building a machine which would be sustained at a speed of eighteen miles per hour, and then finding a locality where winds of this velocity were common. With these conditions a rope attached to the machine to keep it from floating backward would answer very nearly the same purpose as a propeller driven by a motor, and it would be possible to practise by the hour, and without any serious danger, as it would not be necessary to rise far from the ground, and the machine would not have any forward motion151 at all. We found, according to the accepted tables of air pressure on curved surfaces, that a machine spreading 200 square feet of wing surface would be sufficient for our purpose, and that places would easily be found along the Atlantic coast where winds of sixteen to twenty-five miles were not at all uncommon. When the winds were low it was our plan to glide from the tops of sandhills, and when they were sufficiently strong to use a rope for our motor and fly over one spot. Our next work was to draw up the plans for a suitable machine. After much study we finally concluded that tails were a source of trouble rather than of assistance, and therefore we decided to dispense with them altogether. It seemed reasonable that if the body of the operator could be placed in a horizontal position instead of the upright, as in the machines of Lilienthal, Pilcher, and Chanute, the wind resistance could be very materially reduced, since only one square foot instead of five would be exposed. As a full half horse-power would be saved by this change, we arranged to try at least the horizontal position. Then the method of control used by Lilienthal, which consisted in shifting the body, did not seem quite as quick or effective as the case required; so, after long study, we contrived a system consisting of two large surfaces on the Chanute double-deck plan, and a smaller surface placed a short distance in front of the main surfaces in such a position that the action of the wind upon it would counterbalance the effect of the travel of the centre of pressure on the main surfaces. Thus changes in the direction and velocity of the wind would have little disturbing effect, and the operator would be required to attend only to the steering of the machine, which was to be effected152 by curving the forward surface up or down. The lateral equilibrium and the steering to right or left was to be attained by a peculiar torsion of the main surfaces, which was equivalent to presenting one end of the wings at a greater angle than the other. In the main frame a few changes were also made in the details of construction and trussing employed by Mr Chanute. The most important of these were: (1) The moving of the forward main crosspiece of the frame to the extreme front edge; (2) the encasing in the cloth of all crosspieces and ribs of the surfaces; (3) a rearrangement of the wires used in trussing the two surfaces together, which rendered it possible to tighten all the wires by simply shortening two of them.鈥? The letter to Lord Seely was duly written, and this time in Castalia's own words. Algernon refused to assist her in the composition of it, saying, in answer to her appeals, "No, no, Cassy; I shall make no suggestion whatsoever. I don't choose to expose myself to any more grandiloquence from your uncle about letters being 'written by your hand, but not dictated by your head.' I wonder at my lord talking such high-flown stuff. But pomposity is his master weakness." 开心网 五月色婷婷 开心网宝贝五月王老撸 Of the two vessels, R.34 appeared rather more airworthy than her sister ship; the lift of the ship justified the carrying of a greater quantity of fuel than had been provided for, and, as she was considered suitable for making a Transatlantic crossing, extra petrol tanks were fitted in the hull and a new type of outer cover was fitted with a view to her making the Atlantic crossing. She made a 21 hour cruise over the North of England and the South of Scotland at the370 end of May, 1919, and subsequently went for a longer cruise over Denmark, the Baltic, and the north coast of Germany, remaining in the air for 56 hours in spite of very bad weather conditions. Finally, July 2nd was selected as the starting date for the cross Atlantic flight; the vessel was commanded by Major G. H. Scott, A.F.C., with Captain G. S. Greenland as first officer, Second-Lieut. H. F. Luck as second officer, and Lieut. J. D. Shotter as engineer officer. There were also on board Brig.-Gen. E. P. Maitland, representing the Air Ministry, Major J. E. M. Pritchard, representing the Admiralty, and Lieut.-Col. W. H. Hemsley of the Army Aviation Department. In addition to eight tons of petrol, R.34 carried a total number of 30 persons from East Fortune to Long Island, N.Y. There being no shed in America capable of accommodating the airship, she had to be moored in the open for refilling with fuel and gas, and to make the return journey almost immediately. 69 鈥楬aving now demonstrated the practicability of making a steam-engine fly, and finding nothing but a pecuniary loss and little honour, this experimenter rested for a long time, satisfied with what he had effected. The subject, however, had to him special charms, and he still contemplated the renewal of his experiments.鈥? 鈥淚鈥檒l think of it,鈥?smiled Martin. Horatia. You shall hear鈥攊t has been done before. You will aid me in the execution of it. �