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An Encyclopedia of the History of Technology part 69

An Encyclopedia of the History of Technology part 69. This one of a kind encyclopedia presents the entire field of technology from rudimentary agricultural tools to communication satellites in this first of its kind reference source. Following an introduction that discusses basic tools, devices, and mechanisms, the chapters are grouped into five parts that provide detailed information on materials, power and engineering, transportation, communication and calculation, and technology and society, revealing how different technologies have together evolved to produce enormous changes in the course of history | PART THREE TRANSPORT consisted of a winged Orbiter craft with three main engines using liquid oxygen and hydrogen fuel supplied by an external tank plus two solid fuel rocket boosters. This hybrid rocket combination has a capability of carrying 29.5 tonnes into low earth orbit. The external tank is lost during launch but the solid boosters are re-used and the Orbiter re-enters the atmosphere after the mission and lands like a conventional aircraft on a runway. Orbiter s main engines were a major breakthrough in rocket technology. They were designed to be re-usable and throttleable as well as having the largest specific impulse thrust per kilogram of propellant of any previous engine. Up to the end of 1985 over 20 Shuttle missions had been performed since the first launch on 12 April 1981. Whereas the development history of American launch vehicles can be easily traced the same cannot be said for the other space power the Soviet Union. The early Sputniks were launched by a vehicle devised from the SS-6 Sapwood ICBM with a gross lift-off weight of 267 000kg 589 000lb . The A1 A2 and A3 vehicles followed each with a greater launch capability than the last. The A2e was a basic SS-6 plus an additional stage on the A2 and was first flown in 1961 for the Venus fly-by missions. It was also used for the interplanetary lunar and other deep space probes such as Prognoz. Later vehicles have designations C1 D1 F1 F2 and G although few details have been released of these. What is remarkable about Soviet rocketry is that many of the vehicles used in the 1980s date back to the late 1950s and early 1960s and it seems that little real development took place after these earliest designs were developed. Other nations and consortiums of nations have developed their own launch vehicles. Europe has the Ariane vehicle a four-stage launcher capable of placing a 1700kg 3750lb satellite into low earth orbit. The UK s only launch vehicle Black Arrow successfully launched the X3 Prospero .