Unit I. Development of flying vehicles

Text 1. Development of rockets

Part I

The technology of rocket propulsion appears to have its origins in the period AD 1200–1300 in Asia, where the first “propellant” (a mixture of saltpetre, sulfur, and charcoal called black powder) had been in use for about 1, 000 years for other purposes. As is so often the case with the development of technology, the early uses were primarily military. Powered by black powder charges, rockets served as bombardment weapons, culminating in effectiveness with the Congreve rockets (named for William Congreve, a British officer who was instrumental in their development) of the early 1800s. Performance of these early rockets was poor by modern standards because the only available propellant was black powder, which is not ideal for propulsion. Military use of rockets declined from 1815 to 1936 because of the superior performance of guns.

During the period 1880–1930 the idea of using rockets for space travel grew in public interest. Stimulated by the conceptions of such fiction writers as Jules Verne, the Russian scientist Konstantin E. Tsiolkovsky worked on theoretical problems of propulsion-system design and rocket motion and on the concept of multistage rockets. Perhaps more widely recognized are the contributions of Robert H. Goddard, an American scientist and inventor who from 1908 to 1945 conducted a wide array of rocket experiments. He independently developed ideas similar to those of Tsiolkovsky about spaceflight and propulsion and implemented them, building liquid- and solid-propellant rockets. His developmental work included tests of the world's first liquid-propellant rocket in 1926. Goddard's many contributions to the theory and design of rockets earned him the title of father of modern rocketry. A third pioneer, Hermann Oberth of Germany, developed much of the modern theory for rocket and spaceflight independent of Tsiolkovsky and Goddard. He not only provided inspiration for visionaries of spaceflight but played a pivotal role in advancing the practical application of rocket propulsion that led to the development of rockets in Germany during the 1930s.

Due to the work of these early pioneers and a host of rocket experimenters, the potential of rocket propulsion was at least vaguely perceived prior to World War II, but there were many technical barriers to overcome. Development was accelerated during the late 1930s and particularly during the war years. The most notable achievements in rocket propulsion of this era were the German liquid-propellant V-2 rocket and the Me-163 rocket-powered airplane. (Similar developments were under way in other countries but did not see service during the war.) A myriad of solid-propellant rocket weapons also were produced, and tens of millions were fired during combat operations by German, British, and U.S. forces. The main advances in propulsion that were involved in the wartime technology were the development of pumps, injectors, and cooling systems for liquid-propellant engines and high-energy solid propellants that could be formed into large pieces with reliable burning characteristics.

Essential vocabulary:

1. propulsion – движение, толчок;

2. propellant – топливо;

3. saltpeter – селитра;

4. sulfur – сера;

5. charcoal – древесный уголь;

6. weapon – оружие;

7. available – доступный;

8. multistage – многоступенчатый;

9. to implement – выполнять, осуществлять;

10. to provide – снабжать, обеспечивать;

11. inspiration – вдохновение;

12. visionary – мечтатель, провидец;

13. pivotal – центральный, основной;

14. to perceive – воспринимать;

15. achievement – достижение;

16. to accelerate – ускорять;

17. missile – реактивный снаряд, ракета;

18. pump – помпа, нагнетатель воздуха;

I. Give the English equivalents of the following phrases:

- ракетное топливо;

- ракеты служили в качестве бомбардировщиков;

- практическое применение ракет;

- ракета с жидким топливом;

- технология развития нагнетателя воздуха, инжектора и охладительной системы;

- самые знаменитые достижения в ракетостроении;

II. Give definitions to the following words:

rocket, weapon, flight, achievement, propulsion

III. Answer the following questions:

1). When did the technology of rocket propulsion appear for the first time?

2). Who worked on theoretical problems of propulsion-system design in our country?

3). Why was the development of rockets accelerated during the war years?

4). Who conducted a wide array of rocket experiments from 1908 to 1945?

5). What other outstanding rocket developers do you know? What are their achievements in rocketry? Make a short presentation in your group.

Text 2. Development of rockets

Part II

From 1945 to 1955 propulsion development was still largely determined by military applications. Liquid-propellant engines were refined for use in supersonic research aircraft, intercontinental ballistic missiles (ICBMs), and high-altitude research rockets. Similarly, developments in solid-propellant motors were in the areas of military tactical rocket applications and high-altitude research. Bombardment rockets, aircraft interceptors, antitank weapons, and air-launched rockets for air and surface targets were among the primary tactical applications. Technological advances in propulsion included the perfection of methods for casting solid-propellant charges, development of more energetic solid propellants, introduction of new structural and insulation materials in both liquid and solid systems, manufacturing methods for larger motors and engines, and improvements in peripheral hardware (e.g., pumps, valves, engine-cooling systems, and direction controls). By 1955 most missions called for some form of guidance, and larger rockets generally employed two stages. While the potential for spaceflight was present and contemplated at the time, financial resources were directed primarily toward military applications.

The next decade witnessed the development of large solid-propellant rocket motors for use in ICBMs, a choice motivated by the perceived need to have such systems in ready-to-launch condition for long periods of time. This resulted in a major effort to improve manufacturing capabilities for large motors, lightweight cases, energetic propellants, insulation materials that could survive long operational times, and thrust-direction control. Enhancement of these capabilities led to a growing role for solid-rocket motors in spaceflight. Between 1955 and 1965 the vision of the early pioneers began to be realized with the achievement of Earth-orbiting satellites and manned spaceflight. The early missions were accomplished with liquid-propulsion systems adapted from military rockets. The first successful “all-civilian” system was the Saturn launch vehicle for the Apollo Moon-landing program, which used five 680, 000-kilogram-thrust liquid-propellant engines in the first stage. Since then, liquid systems have been employed by most countries for spaceflight applications, though solid boosters have been combined with liquid engines in various first stages of U.S. launch vehicles (those of the Titan 34D, Delta, and Space Shuttle) and solid-rocket motors have been used for several systems for transfer from low Earth orbit to geosynchronous orbit. In such systems, the lower performance of solid-propellant motors is accepted in exchange for the operational simplicity that it provides.

Since 1965, missions have drawn on an ever-expanding technology base, using improved propellants, structural materials, and designs. Present-day missions may involve a combination of several kinds of engines and motors, each chosen according to its function. Because of the performance advantages of energetic propellants and low structural mass, propulsion systems are operated near their safe limits, and one major challenge is to achieve reliability commensurate with the value of the (sometimes human) payload.

Edward W. Price

Essential vocabulary:

1. application – применение;

2. engine – двигатель;

3. high-altitude – высотный;

4. interceptor – истребитель-перехватчик;

5. to cast – бросать;

6. charge – заряд;

7. target – цель, мишень;

8. insulation – изоляция, изоляционный материал;

9. manufacturing – производство, изготовление;

10. improvement – улучшение;

11. valve – клапан;

12. to contemplate – созерцать, обдумывать, рассматривать, предполагать;

13. satellite – спутник;

14. to accomplish – совершать, выполнять, достигать;

15. thrust – тяга, толчок;

16. booster – ракета-носитель, стартовый двигатель;

17. to commensurate – соответствовать, соразмерять;

18. payload - полезная нагрузка;

I. Give the English equivalents of the following phrases:

- разработка высотных ракет;

- ракеты для воздушных и наземных целей;

- жидкотопливные двигатели используются в сверхзвуковых самолетах;

- попытка улучшить производственные возможности;

- ракеты, готовые к запуску на длительный период времени;

- выбранный соответственно своей функции;

II. Answer the following questions:

1). What was the main usage of liquid-propellant engines?

2). What rockets were among the primary tactical application

3). What was the first successful ” all-civilian” program?

4). What did the technological advances in propulsion include in the beginning of the 50’s?

5). What were the first improvements in peripheral hardware?

6). What other information about rocketry and its development do you know?

Find some extra information and make a short presentation in your group.

Text 3. The Wright brothers

Wilbur and Orville Wright in the course of their experiments came increasingly to consider Cayley's diagram of how a wing works, particularly the role played the speed of the wind passing over the wing. This led them to seek a site with a strong and persistent wind (the Vogels Mountain where the has just such a high ambient wind, as do the hills near Elmira, N.Y., and Fremont, Calif., classic gliding courses). From the U.S. Weather Bureau the Wrights secured a list of windy sites in the United States, from which they chose the Outer Banks of North Carolina, specifically Kitty Hawk. On Kill Devil Hill there on Dec. 17, 1903, Orville Wright became the first man ever to fly in an aeroplane (as they were at first known), initially using as a frame a biplane of 40-foot 4-inch wingspan and equipped with the 12-horsepower engine. He lifted off the ground in a 20–27-mile/h wind and flew a distance of 120 feet in 12 seconds. Having a strong wind certainly aided in that accomplishment, but the brothers soon demonstrated that such a wind was not absolutely essential.

After further experiments at Kitty Hawk they returned to Dayton to build a second plane, Flyer No. 2. Neither the balloons and dirigibles nor the earlier ornithopter and glider experiments had produced flight: what they had done was to harness the dynamics of the atmosphere to lift a craft off the ground, using what power (if any) they supplied to steer. The Wrights initially used atmospheric dynamics to help in lifting the plane, but they subsequently demonstrated that they were able to lift a plane off the ground in still air.

In the long run their most significant invention was a way to steer the plane. After carefully watching a great number of birds, they became convinced that birds directed their flight by internally warping their wings, distorting them in one fashion or another. To do this in their plane, the Wrights constructed a ridged but distorted wing that might, through the use of wires fixed to the edge of the wing, be flexed to pass through the air in changing directions. This distortable wing was relatively misunderstood by other early plane experimenters.

During the summer of 1904 the Wrights made 105 takeoffs and managed to fly on a circular course up to 2.75 miles for a sustained flight that lasted 5 minutes 4 seconds. Because they took a proprietary view of their invention, publicity about their work was minimal. After further trials in 1905 they stopped their experiments, using the time to obtain patents on their contribution. Only in 1908 did they break their secrecy when Wilbur Wright went to France to promote their latest plane.

Essential vocabulary:

to consider – рассматривать, считать, решать
to pass over – пропускать, переходить, обновить
to seek - искать
site - место
persistent – устойчивый (постоянный)
hill - холм
to glide – скользить, планировать
to secure – закреплять (обозначать)
frame - рамка
biplane - биплан
wingspan – размах крыльев
to equip – оборудовать, оснащать
engine - двигатель
to aid - помогать
accomplishment – выполнение, осуществление
essential – главный, основной
harness – упряжь (зд. обуздать, поймать)
to supply – поставлять, обеспечивать
steer - управление
subsequently - впоследствии
significant invention – важное открытие
to convince - убеждать
to warp - поворачивать
to distort - искажать
fashion - способ
ridged - гребенчатый
wire – шнур, провод
edge – край, ребро
sustained – поддерживать, выдерживать
proprietary – личный, патентованный
contribution - вклад

I. Answer the following questions:

Why did the Wright brothers seek a site with a strong and persistent wind?
Who was the first man to fly in an aeroplane?
Why did neither balloons and dirigibles nor ornithopter experiments produce flight?
What was the most significant invention of the Wright brothers?
How many flights did the Wrights make during the 1904?
When did the Wrights stop experiments and break their cecrecy?

II. Find the English equivalents of the following phrases in the text:

· сильный постоянный ветер

· вскоре продемонстрировали

· абсолютно не важен (нужен)

· зафиксированный на краю крыла

· изогнутое крыло

· подняться с земли (взлететь)

· движение (динамика) атмосферы

· один способ или другой

· расстояние в 120 футов

· изменяющиеся направления

· произвести полет (полететь)

· получить патент на изобретение

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