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Transportation for the 21st century





Experts estimate that in the 21st century we will go by rocket from New York to Tokyo in 30 minutes. We will be able to reach any point on the globe from any other point through tunnels deep in the earth. The prospect is adventurous and exciting. It's possible, that within the next two of three decades we will be riding in remote-controlled electronic cars.

Trips through metropolitan areas will be made on quiet, swift buses travelling on separate express lines of city streets. Helicopters may carry whole buses loaded with passengers from point to point above city traffic. "Flying crane" helicopters soon may help solve the complicated problem of getting passengers from the centre to the airport and back again.

Most of the advances in air transportation will materialize within the next few years. The largest airplane ever designed for commercial service, capable of seating nearly 500 passengers, is already being built.

Supersonic transport prototypes now in development are forerunners of a new generation of 1,800 miles per hour passenger jet-liners.

The "ideal" short-haul air transport is a vertical or short take-off and landing aircraft that can fly 30 to 45 passengers right into the heart of a city or its suburbs trips up to 260 miles.

Mankind has entered an age of high speeds, pressures, and temperatures which could be generated' and withstood only with the help of new and hitherto unknown materials.

In the 1920s the top speed of an airplane was not more than 200 kilometres per hour, the load per square metre of the wing area was about 50 kilograms. The main construction material was wood. In our day, the speed, of aircraft, even passenger planes, is approaching 3,000 kilometres per hour, loads may be as high as 600 kilograms per square metre of wing. The turbine that drives such an aircraft is not only a miracle of design, it is also a miracle of materials strength. Its blades, for example, rotate at a tremendous speed and at the temperature greater than 1,000° Centigrade. The given examples are sufficient to indicate the complexity of materials studies today and the extent to which.progress in the near or more distant future depends on them.

Of tremendous importance is the creation of new materials. Chemists engaged in polymer research have produced the world's best synthetic materials.

Metallurgists studying a new class of aluminium alloys have produced a very durable alloy which is being used in aircraft and rocket engineering. The alloy helps reduce the weight of apparatus substantially, thereby I effecting a considerable saving of materials.

Plastics are employed in a number of aircraft engine applications and I have successfully displaced metals in jet turbine impellers where the high I fatigue resistance of the material is of great importance. If suitable higher I temperature plastics, were developed, it is quite feasible that turbines will one day be all of plastic construction.

At present a great deal of research and development is being carried out to produce special grades of plastics for space vehicles.

For space travel, resistance to cosmic radiation is an important consideration. Many plastic materials possess this property, and also offer the advantage of light weight. Astronaut couches, space capsules, missile fuel cases are manufactured of plastic materials.

Some ideas of rapid air transportation are on the drawing boards, some may never get off. Some are already under way and operational, while others may not take shape until the next decade. But changes are taking place, and there are more to come.

Text G

TSIOLKOVSKY'S DREAM NEARS REALIZATION

The young man spent hours over ideas he had put down in a schoolboy's note-book. In a home-made machine he made lots of experiments to see how living things withstood the effects of gravity and acceleration. The date was 1879, in the small Russian village near Ryazan. Konstantin Tsiolkovsky was 22, waiting for a post of a schoolmaster.

The problem at which he worked was interplanetary travel. Though Tsiolkovsky soon began a long career as a teacher of mathematics, man's penetration into space remained his life-long study.

In 1883 he noted that the rocket would be the only man-made instrument able to reach space. The prediction was published only in 1954, when his collected works were printed by the Soviet Academy of Sciences. The mathematical terms of space travel were worked out by Tsiolkovsky as early as 1895 in a manuscript "The Exploration of Cosmic Space by Reaction-Propelled Appa­ratus". When it was published in 1903, Tsiolkovsky won immediate international recognition, especially among the pioneers of aviation science.

Tsarist Russia had no research money for the modest school-teacher of Kaluga, and to get money for his re­searches Tsiolkovsky tried to publish his book "Outside the Earth" in 1916, in which he described the imaginary flight of a manned rocket ship in orbit about the earth.

It was only in 1920 that the book was published and it fired the imagination of other scientists in our country; as well as abroad. In 1929 when Tsiolkovsky was 72, Pro­fessor Herman Obert, a German scientist, wrote to him "You kindled this fire. We shall not let it die. It is necessary that man's greatest dream should be realized."

In the book "Outside the Earth" Tsiolkovsky assem­bled a group of famous scientists in an imaginary moun­tain laboratory: Galileo, Newton, Laplace, Helmbolz, Franklin and a modest Russian named Ivanov. At their disposal is an army of the world's best engineers and technicians. The year is 2017.

Together the scientists work out the theories of cosmic flight. They test rockets and fuels, discuss ways of living aboard a rocket, and design a 300-ton spaceship. The voy­age that follows is described very vividly. Some of the details of this imaginary flight you have seen in reality on your own TV screen—weightless objects floating around a cosmonaut, the black sky of space, the blast-off of a man carrying rocket.

In 1935 Tsiolkovsky wrote to Soviet youth: "All who are occupied with writing science fiction are doing good work; they excite interest, promote the working of the brain and bring into being people 4 who will work on grand projects inthe future."

This was the last year of his life. A few days before he died, Tsiolkovsky's letter to the Central Committee of the CPSU appeared in Pravda. He wrote that all his life he had been fighting to help mankind and he was leav­ing his works to the Soviet Government and the Commu­nist Party and he was sure they would successfully com­plete this work.

 

 

 

 


UNIT 6

Date: 2015-09-05; view: 1033; Нарушение авторских прав; Помощь в написании работы --> СЮДА...



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