/kloc-at the age of 0/0, Kelly heard that the French had completed the first manned balloon flight and began to have an interest and yearning for aviation. 1792, he made a series of experiments with bamboo dragonfly, a porcelain toy, and made a "China Gyro" out of iron. He tugged at the rope to make it spiral up quickly, but he could reach a height of 27 meters. 1804, he wrote the first paper on the principle of human flight. In the same year, Kelly made a kite that looked like a big bird. He put a pod under the kite and let people sit in it. Then he drove the carriage and pulled the kite forward. As a result, the kite flew far from the ground.
1809, Kelly published a paper entitled "On Air Navigation" in Nicholson Journal of Natural Philosophy, which quickly caused a sensation and was reprinted in the western world 100. In this paper, Kelly believes that the old idea that humans want to imitate birds flying with wings for many years must be abandoned, and it is entirely possible to manufacture fixed-wing aircraft. He described the outline of modern aircraft in detail, which laid the foundation for later aerodynamics. Regarding the wing, he thinks that we should take a little angle when designing the wing surface, so as to obtain proper stability, that is, the dihedral angle of modern aircraft. He also suggested that the tail wing must have vertical and horizontal rudder surfaces, which is exactly the same as modern aircraft. He thinks the plane must be streamlined. According to his calculation, if the resistance of 1 kg can be reduced, the load capacity can be increased by 66 kg without increasing horsepower. He also discussed the relationship between speed and lift, wing loading, how to reduce the weight of aircraft, and even the internal combustion engine as power. To prove these principles, he once built an unmanned glider to do experiments.
In the era of Kelly's life, human beings can only use heavy steam engines to provide power, and how to solve the power problem of aircraft has become the most troublesome thing. Kelly tried to make a light steam engine to drive the plane, but failed. To this end, he wrote sadly: "The only thing I can't solve in my invention is a power problem. I am convinced that this noble and precious technology will be successful in the near future. The speed of the plane will reach 40 ~ 160 kilometers per hour. People use it to transport people, goods and property, which is far safer than sailing on water. "
1837, Kelly published another article about aviation in Mechanical Engineering magazine, reaffirming his early ideals and advocating people to do more experiments. By 1848, Kelly was 75 years old. Seeing that the light engine will appear in the foreseeable future, he is determined to continue the unpowered glider experiment. 1849, he built a three-wing glider with the pilot sitting in the hanging basket. He wrote in his notes: "There was a boy 10 years old on the plane, who flew a few yards from top to bottom;" If manpower takes off against the wind, it can float the same distance. " He didn't say who the boy was, but it was undoubtedly the first manned glider flight in human history.
1853, Kelly wrote an article describing the flight of unmanned gliders and sent it to the French Aviation Society, entitled "Improved 1853 Rudder Glider". Just this year, Kelly conducted another flight test in Yorkshire. The aircraft used this time is similar to the kite he used in 1804, except that there is no rope. After the experiment began, I saw a brave young man running down a gentle hillside with this big kite and then flying on a prominent rock. Cross the valley to the opposite hillside. Although it has been pointed out that Kelly's "kites without wires" are equipped with movable "flapping wings", their operation is complicated and the flying effect is not ideal. However, it is undoubtedly the original glider of mankind.
In 1853, Kelly also made a glider heavier than the glider in 1849, with a brake device. In this experiment, he sat his coachman in the driver's seat. Kelly did not leave a written record of how far she flew, but according to Kelly's granddaughter who witnessed the flight, the flight distance was about 450 meters. Kelly was not only interested in aviation, but also designed shells for the British navy, which showed great prestige during the Napoleonic Wars. He invented the heat engine in 1807 and obtained a patent, which was widely used in industry. He designed a spoke wheel for a glider in 1825, and this invention is still adopted by bicycles. In addition, he invented the railway automatic braking device and made many valuable contributions in acoustics, optics, electricity and sewer engineering. 1858, 84-year-old Kelly died in the tears of his wife Shana. Shortly before his death, he wrote this sentence in his notebook: "Here you are, friend who checked your notes!" " I have already left, I hope you can find smart flowers in these graffiti. "
Interestingly, in 197 1 year, British pilot Lieutenant Colonel Bolu made a glider exactly like that year according to the notes left by Kelly, and it was a great success, which fully proved how great Kelly's design was before 1 18 years ago.