Essential vocabulary:

1. thrust force – сила тяги

2. to exert – оказывать, действовать

3. plane of rotation – плоскость вращения

4. to hover - реять

5. drag force – тормозная сила

6. to tip - наклоняться

7. mast - мачта

8. to tilt – наклонять

9. pitch angle – угол наклона

10. torque – вращающий момент

11. offset – офсет, смещение, сдвиг

12. gyroscopic precession effect – эффект гироскопической прецессии

13. retreat - отступление

14. rolling – прокрутка, прокатывание

15. flapping hinge – маховик (шарнир), закрылок

16. hub – узел, втулка

17. feathering – вращение (по принципу пера), резать крылом воздух

18. to permit – позволять, разрешать

19. to attach – прикреплять

20. to increase – увеличивать, повышать

21. to decrease – снижать, уменьшать

22. to equalize - выравнивать

23. to dampen out – демпфировать, тормозить

24. to absorb – поглощать, впитывать

25. to contribute – содействовать

26. coning – конус

27. bending – изгиб

28. centrifugal force – центробежная сила

29. acceleration – ускорение

30. drift – парение, дрейф

I. Answer the following questions:

1. What are the total lift and thrust forces in a helicopter exerted to?

2. How can a helicopter achieve a forward (sideward, rearward) flight?

3. How does the pilot control the thrust of the tail rotor?

4. What is the gyroscopic precession effect of the rotor?

5. What forces do you know acting upon only a helicopter?

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

• сила подъема

• параллельно земле

• единичный вектор

• направленный вниз (вверх)

• движение вертолета

• обычный самолет

• ровное поднятие в воздух

• похожий эффект

• в условиях безветрия

• изменение угла наклона

III. Look at the groups of words below. Which word is the odd one?

1. a) helicopter b) aircraft c) rocket d) automobile

2. a) weight b) acceleration c) velocity d) speed

3. a) forward b) rearward c) drift d) sideward

4. a) blade b) wind c) rotor d) fuselage

5. a) lift force b) drag force c) power d) thrust force

6. a) coning b) moving c) feathering d) bending

Text 6. Spacecraft

Unmanned spacecraft are called satellites when they operate in Earth orbit and space probes when launched on a trajectory away from the Earth toward other bodies or into deep space. Whereas probes are designed for scientific missions, satellites have a wide variety of civil and military applications such as weather observation, remote sensing, surveillance, navigation, communications, and television and radio broadcasting.

In the civil market, satellites have become the backbone of long-distance telephone and multinational television broadcasting, as well as the basis for new communications options such as global mobile telephones. All major telecommunications entities use satellites as key network nodes in constellations ranging from three or four large spacecraft in geosynchronous orbit to more than 100 smaller vehicles in low Earth orbit. Many companies compete in the commercial satellite manufacturing business. In the United States they include Boeing, the world's largest supplier of TV and communications satellites. In Europe, Astrium predominates. Canada, Brazil, Australia, Japan, China, India, and Israel possess nascent industries and have built and orbited satellites. Several other countries have built subsystems and experiments for American and European unmanned and manned spacecraft, as has Russia, which has also developed and launched navigation-satellite constellations for worldwide use.

Manned spacecraft impose far greater technical challenges than unmanned systems because of the equipment necessary to sustain human crews in space and bring them back to the Earth. Current manned spacecraft are the most complex aerospace vehicles. In use at the turn of the 21st century were the U.S. space shuttle, the Russian spacecraft Soyuz, the Russian space station Mir ( taken out of orbit in March 2001), and the International Space Station (ISS). The technologies of the first three craft date back to the 1960s and '70s. In the late 1990s, in concert with Russia, the European Space Agency, Japan, and Canada, the United States undertook construction of the ISS, a modular complex of habitats, laboratories, trusses, and solar arrays intended to be a permanently inhabited outpost in Earth orbit. Manufacturers of major ISS components outside the United States include EADS (France-Germany-Spain), Alenia (Italy), and Mitsubishi (Japan). In 1998 the first two ISS modules were launched and joined in space, and other components were subsequently added. In November 2000 the first three-person crew, an American and two Russians, occupied the still-expanding station.

Most unmanned scientific spacecraft and all manned space hardware are procured by government agencies. Specific examples are NASA and the National Oceanic and Atmospheric Administration (NOAA) in the United States, the European Space Agency (ESA), the Russian Space Agency (RKA), the National Space Development Agency (NASDA) in Japan, the Chinese Space Agency in China, and the Indian Space Research Organisation (ISRO) and Indian Space Agency in India.

Essential vocabulary :

1. probe – зонд;

2. surveillance – надзор, наблюдение;

3. broadcasting – трансляция;

4. backbone – основной;

5. option – цель;

6. entity – объект;

7. node – узел;

8. constellation – созвездие;

9. to predominate – преобладать;

10. to possess – владеть;

11. nascent – молодой, начинающий;

12. to impose – предназначать;

13. challenge – вызов, требование;

14. to sustain – выдерживать, поддерживать;

15. to undertake – предпринимать, браться;

16. habitat – среда;

17. truss – ферма;

18. outpost – форпост;

19. subsequently – впоследствии;

20. hardware – аппаратное обеспечение;

21. to procure – приобретать;

22. array – массив;