T. Spars are span-wise members of the wing structure. Can you guess the meaning of the word “span-wise”?
S. I think I can. Is it “повздовжній / продольный”?
T. Yes, you are right. Some designs have one spar and some have two. The wing with many spars is called a multi-spar wing. Can you translate the word "multi-spar”?
S. “Багатолонжеронний / Многолонжеронный”.
T.Remember, we have come across such words as "multiplane" and "multinational". Now we have learned one more word with prefix multi - "multispar". What is the function of the spar?
S. To carry the main wing load.
T. That’s right. Another structural member of the wing is a rib “нервюра / нервюра”. (Fig.I.3.7). Ribs are attached to the spars. They are chord-wise members, forming the contour of the wing. So, what does “chord-wise” mean?
Fig.I.3.7. A rib
S. “Chord-wise” means “поперечний / поперечный”, doesn’t it?
T. Yes, it does. Ribs shape the wing cross-section (поперечний розріз / поперечное сечение). The wing is covered with the skin. Can the skin carry air loads?
S. I guess it can.
T. In case the skin carries loads it is called a stressed-skin construction (працююча обшивка / работающая обшивка). The skin is supported by stringers (Fig.I.3.8.) The Ukrainian and Russian equivalents sound the same – “стрингер / стрингер”.
S. Where are stringers located?
T. They go parallel and between the spars. The stringers reinforce the skin. “To reinforce” means “підсилювати / усиливать”.
Exercise 14. Read, translate and give the gist of text 2.
Text 2. Structural Members of the Wing The internal structure of a wing is made up of spars, stringers or stiffeners, ribs. The spars and stringers run span-wise, that is along the length of the wing from the fuselage to the tip of the wing. Some designs have one sраr and some have two. In general, wing construction is based on one of three fundamental designs: monospar, multi-spar and box-spar type. Modifications of these basic designs may be adopted by various manufacturers.
The monospar wing incorporates only one main longitudinal member in its construction. Ribs supply the necessary contour or shape to the airfoil.
The multi-spar wing incorporates more than one main longitudinal member in its construction. To give the wing its shape, ribs are often included.
The box-spar type of wing construction uses two main longitudinal members with connecting bulkheads not only to increase strength and reduce weight but it also enables the wing to serve as a fuel tank when properly sealed.
Spars are the principal structural members of the wing. They run parallel to the lateral axis, toward the tip of the wing, and are usually attached to the fuselage. They may be made of metal or wood depending on the construction. The function of the spar is to carry the main air load.
The ribs are attached to the spars. They extend from the wing leading edge to the trailing edge and make up the framework of the wing. The ribs give the wing its cambered shape and transmit the loads from the skin and stringers to the spars. Ribs are manufactured from metal or wood.
The skin covers the wing. The skin is supported by the stringers. They go parallel and between the spars and reinforce the skin. The skin is a part of the wing structure and it carries part of the wing stresses. In case the skin carries the load, it is called a stressed skin construction. From the skin the loads are transmitted to the ribs and from the ribs to the spars.
Exercise 15. Translate the verb – noun pairs.
To unite – unit, to provide – provision, to depend – dependence, to vary – variety, to determine – determination, to design – designer, to act – action, to attach – attachment, to direct – direction, to carry – carriage, to construct – construction, to lose – loss, to transmit – transmission, to lead – leader, to measure – measurement, to divide – division, to define – definition, to move – motion, to differ – difference, to connect – connection, to cover – coverage, to reduce – reduction, to extend - extension.
Exercise 16. Translate the verb combinations.
To depend on the construction, to transmit loads, to reinforce the skin, to carry the main load, to go parallel to the spars, to reduce weight, to be made of wood, to be sealed properly, to be made of metal, to be called a multi-spar wing, to be attached to the spar, to increase strength, to serve as a fuel tank.
Exercise 17. Translate into English.
1. Лонжерони та стрінгери розташовані вздовж крила від фюзеляжу до закінцівки крила.
1. Лонжероны и стрингеры рас-положены вдоль крыла от фюзеляжа до законцовки крыла.
2. Лонжерони проходять паралельно поперечній осі і кріпляться до фюзеляжу.
2. Лонжероны проходят параллельно поперечной оси и крепяться к фюзеляжу.
3. Вони можуть бути виготовлені з металу або дерева.
3. Они могут быть изготовлены из металла или дерева.
4. Функція лонжерона – нести основне повітряне навантаження.
4. Функция лонжерона – нести основную воздушную нагрузку.
5. Конструкція крила залежить від призначення літака.
5. Консрукция крыла зависит от назначения самолета.
6. Трьома основними типами конструкції крила є: однолонжеронне, багатолонжеронне крило і крило з коробчастим лонжероном.
6. Тремя основними типами консрукции крыла являются: однолонжеронное, многолонжеронное крыло и крыло с коробчатым лонжероном.
7. Нервюри (перегородки) кріпляться до лонжеронів і несуть навантаження.
7. Нервюры (перегородки) крепятся к лонжеронам и несут нагрузки.
8. Нервюри надають крилу вигнуту форму і передають навантаження з обшивки на лонжерони.
8. Нервюры придают крылу выгнутую форму и передают нагрузку от обшивки на лонжероны.
9. Стрінгери проходять паралельно між лонжеронами і підсилюють обшивку.
9. Стрингеры проходят параллельно между лонжеронами и усиливают обшивку.
10. З обшивки навантаження передаються на нервюри, а з нервюр на лонжерони.
10. От обшивки нагрузки передаются на нервюры, а от нервюр на лонжероны.
11. Якщо обшивка крила несе навантаження, вона називається працюючою обшивкою.
11. Если обшивка крыла несет нагрузку, она называется работающей обшивкой.
Exercise 18. Put subject questions after the model.
The stringers reinforce the skin.
What reinforces the skin?
1. The bulkheads increase strength and reduce weight of a wing. 2. The ribs form the shape of the wing. 3. The spars run along the length of the wing. 4. The spars may be madeof metal. 5. The stringers go parallel to the spars. 6. The wing is covered with the skin. 7. A stressed skin construction carries air loads. 8. The air loads are transmitted to the ribs.
Exercise 19. Put questions to the italicized words.
1. The wing tip is bolted to the outboard end of the wing panel. 2. Basic wing structure consists of left, center and right wing boxes.3. Wing boxes are built up from front spar, rear spar, stringers, ribs and top and bottom skin.4. Damaged skin section may be repaired quickly by its replacement. 5. The ribs provide the necessary contour or shape to the wing and carry the loads. 6. The wing tip is often a removable unit. 7. A wing that uses a box-beam design gives additional strength and contour to the wing. 8. The ribs are reduced in weight by holes punched in the metal.
Exercise20. Compose dialogues on “Wing structural members.”
Exercise 21. Memorize the active vocabulary.
1. дорога; шлях 2. маршрут, траса 3. слід 4. колія 5. напрямний пристрій; напрямна 6. напрям; курс; лінія шляху (польоту); траєкторія 7. канал; тракт 8. прокладати маршрут, трасу 9. стежити; простежувати
1. дорога; путь 2. маршрут, трасса 3. след 4. колея 5. направляющее устройство; направляющая 6. направление; курс; линия пути (полета); траектория 7. канал; тракт 8. прокладывать маршрут, трассу 9. следить; прослеживать
Exercise 22. Practise out the dialogue.
T. Look at the picture (Fig.I.3.9.) These are flaps. The flaps are auxiliary surfaces of the wing. The word "auxiliary" means “допоміжний / вспомогательный”. Where are flaps located?
S. They are hinged to the trailing edge of the wing between the ailerons and the fuselage.
Fig.I.3.9. Flaps and ailerons
T. Now let’s consider the function of flaps. When are flaps operated?
S. The flaps are operated during take-off and landing.
T. That’s right. In these cases it is necessary to have enough lift to support the weight of the airplane. Do the flaps provide the main lift?
S. No, I think they provide additional lift. The main lift is provided by the wing proper.
T. Yes, that’s right. What happens with the drag when flaps are deflected?
S. It is increasing.
T. Is it always useful?
S. The drag is useful only during landing.
T. Yes, quite right. For taking-off the flap angle should be small so that increased lift is obtained with little increase in drag. So, what helps to obtain little increase in drag?
S. It is a small flap angle that helps to obtain little increase in drag.
T. Yes, in landing flaps play a very important part, as in landing the increase in drag must be considerable. How is this achieved?
S. Increase in drag is considerable when the flaps arewell down.
T. So, we can see that the flaps permit (дозволяють / позволяют) slower and safer flight, lower landing speeds, steeper angles of descent. The word "safe" means “безпечний / безопасный”, “steep” – “крутий / крутой”. “Descent”(зниження / снижение) is opposite to "climb". What does the word "climb" mean?
S. “To climb” means “набирати висоту / набирать высоту ”.
T. Pay attention to the translation of the words with –er suffix: slower пoвільніший / более медленный, lower – нижчий / более низкий, safer – безпечніший / более безопасный, steeper – крутіший / более крутой. To provide slower landing speed, the flaps are fully deflected during landing. They permit landing on short fields. We may classify flaps according to their mechanical nature into: plain flap (простий закрилок / простой закрылок), split trailing edge flap (щиток / щиток), slotted flap (щілинний закрилок / щелевой закрылок) and Fowler flap (закрилок Фаулера / закрылок Фаулера) (Fig.I.3.10).
Fig.I.3.10. Types of flaps
So, how are flaps classified?
S. We classify flaps according to their mechanical nature.
T. As you can see in the picture in the plain flap the wing trailing edge is deflected downward. In the split trailing edge flap the shape of the upper surface of the wing is unchanged when the flap is lowered. The word "change" means “міняти(cя) / менять(ся)”. And with the prefix “un-" it has a negative meaning. Translate the word "unchanged".
S. “Незмінний / Неизменный.”
Т. Quite right. The split trailing edge flap creates more drag than the plain flap. The word "create" means "створювати / создавать". The Fowler flap moves backward on a track (рейки / рельсы), increasing the wing area, thus providing added lift without increasing drag. So, which of the three flap types is the most efficient in taking off?
S. The Fowler flap is.
T. The slotted flap provides a slot or opening between the wing and the leading edge of the flap. I think you know the translation of the verb "open". And the word “opening” means “отвір / отверстие”. The word "slot" is “щілина / щель”. Where doesthe slotted flap provide a slot?
S. Between the wing and the leading edge of the flap.
T. So, what types of flaps can you name now?
S. I know four types of flaps. They are: plain flap, split trailing edge flap, slotted flap and Fowler flap.
T. Great! Thank you.
Exercise 23. Read, translate and give the gist of text 3.
Text 3. Flaps
The flaps are auxiliary surfaces of the wing used to modify its lift characteristics. They are hinged to the trailing edge of the wing and are practically an extension of the wing. The flaps are located between the ailerons and the fuselage.
The flaps are used during take off and landing. In take off and approach to landing they supply greater lift and drag. In order to leave the ground, the airplane must have enough lift to support its weight. The lift may be increased by increasing the speed, by changing the attitude of the wing or by increasing the camber of the wing. During take-off it is necessary for the speed to be as high as possible in order to shorten the take-off run and get into the air as quickly as possible. It is dangerous for the airplane to increase the angle of attack too much. So, it is possible to increase lift by using flaps. When the flaps are lowered the camber of the wing is increased. It increases drag. That is why during take off the flap angle should be small.
In landing flaps play a very important role. If the flap is well down, the increase in drag will be considerable and the gliding angle will be greater. The flaps permit slower and safer flight, lower landing speeds, steeper angles of descent. During flight and after touchdown they can increase drag for quick deceleration. The flaps permit landing on short fields.
We may classify flaps according to their mechanical nature into plain flaps, split flaps, Fowler flaps and slotted flaps. The plain flap is simply hinged to the wing and forms a part of the wing surface when raised. In the split flap the shape of the upper surface of the wing is unchanged when the flap is lowered. The split flap creates more drag than the plain flap. When the Fowler flap is operated, it slides backward on a track. This increases wing camber, as do the other types of flaps. The Fowler flaps also increase the wing area; thus they provide added lift without increasing drag. The slotted flap provides a slot or opening between the wing and the leading edge of the flap improving the efficiency of the flap.
Exercise 24. Match the synonyms among the following:
Exercise 25. Fill in the blanks with the terms: the leading edge, the upper surface, the trailing edge, drag, lift, the camber.
1. The flaps are hinged to … … of the wing. 2. The slotted flap provides a slot between the wing and … … of the flap. 3. The airplane must have enough … to support its weight. 4. When the flaps are lowered … of the wing is increased. 5. The split flap creates more … than the plain flap. 6. In the split flap the shape of … … of the wing is unchanged.
Exercise 26. Translate and memorize the definitions of the terms.
1. delta wing
a) A design merges the wing and tail of an aircraft into one large flying surface that provides greater aerodynamic advantage in supersonic flight.
b) The complete tail unit of an aircraft that gets its name from the French word for the feathers at the end of an arrow, which it resembles.
c) An extension of the wing used to modify its lift characteristics that is, it supplies greater lift and drag during flight and after touchdown.
d) Movable portion of airplane wings usually located at the trailing edge near the wing tips, making banking possible.
e) A streamlined body, such as a wing, designed to provide lift from the air through which it moves.
Exercise 27. Give definitions to the terms: empennage, airfoil, flap, delta wing, aileron.
Exercise 28. Translate the following sentences.
1. Закрилки – це допоміжні площини, що розташовані на задній кромці крила між елеронами та фюзеляжем.
1. Закрылки – это вспомогате-льные плоскости, расположен-ные на задней кромке крыла между элеронами и фюзеляжем.
2. Закрилки використовуються під час зльоту та посадки.
2. Закрылки используются при взлете и посадке.
3. Підіймальну силу можна збільшити, збільшуючи швидкість, змінюючи положення крила та збільшуючи кривизну крила.
3. Подъемную силу можно увеличить, увеличивая скорость, изменяя положение крыла и увеличивая кривизну крыла.
4. Коли закрилки опускаються, кривизна крила збільшується.
4. Когда закрылки опускаются, кривизна крыла увеличивается.
5. Ми можемо класифікувати закрилки за їх механічною природою.
5. Мы можем классифицировать закрылки согласно их механической природе.
6. Щиток створює більший лобовий опір, ніж простий закрилок.
6. Щиток создает большее лобовое сопротивление, чем простой закрылок.
7. Щілина між крилом і перед-ньою кромкою крила підвищує ефективність закрилка.
7. Щель между крылом и передней кромкой крыла увеличивает эффективность закрылка.
8. Закрилок Фаулера відкочується назад по напрямним рейкам, збільшуючи ефективну площу крила.
8. Закрылок Фаулера откатыва-ется назад по направляющим, увеличивая эффективную площадь крыла.
Exercise 29. Fill in the blanks with prepositions on, of , by, in,to,for, from, with, between and translate the sentences.
1. The flaps are located … ailerons and the fuselage. 2. The flaps permit landing … short fields. 3. The Fowler flap moves backward … a track. 4. It is dangerous … the plane … increase the angle … attack too much. 5. … changing the attitude of the wing we may increase the lift. 6. The wing tips are made … composite materials. 7. Most flaps are hinged … the lower trailing edges … the wings. 8. Leading edge flaps are also used, principally … large high-speed aircraft. 9. Trim tabs free the pilot … constantly adjusting the controls ... flight. 10. In conventional aircraft pilots avoid too high an angle ... attack, which results … a loss of lift.
Exercise30. Put questions to the sentences, beginning them with the given question-words.
1. Extension of the flaps increases the effective wing area.
What …? (3 questions)
2. Take-off flap positions provide high lift and relatively low drag.
What … ? (4 questions)
3. Landing flaps produce high lift and high drag.
What …? (4 questions)
4. When airspeed is reduced, the flaps automatically return to the fully extended position.
When … ? How…? What ...? (2 questions)
5. Minor damage to a flap lower surface does not require flap replacement.
What … ? (3 questions)
Exercise 31. Match the terms with their definitions.
a) An extension of the wing used to modify its lift characteristics
b) The arching curve of an aircraft wing from the front (or “leading”) edge to the rear (or “trailing”) edge
c) A phase of flight where the altitude is increasing
d) A wing supported only where it is attached to the fuselage
5. cantilever wing
e) A loss of lift due to slow airplane speed or attitude
f) A movable part of the leading edge of the wing for increasing lift at low airplane speeds
g) A brace that supports a load, for instance, the structure supporting a wing
Exercise 32. Say whether the following sentences are true or false. Correct the false ones.
1. When the angle of attack is so steep that the airflow over the upper surface of the wing breaks, lift is increased. 2. Cantilever wing is a wing supported only where it is attached to the fuselage, without other supports or braces. 3. Pilots avoid too high an angle of attack which may result in a loss of lift. 4. When the flap is in the “down” (or extended) position it decreases the wing camber and changes the airflow, providing less lift. 5. In take off and approach to landing, flaps supply greater lift and lower drag respectively. 6. We can considerably increase the drag deflecting the flap downward.
Exercise 33. Give definitions to the terms: stall, climb, strut, camber, cantilever wing, flap, slat. Exercise 34. Using Figure I.3.11. and the vocabulary below describe the wing high-lift devices.
13. внутрішній передкрилок / внутренний предкрылок
m) wing leading edge extension
14. зовнішній передкрилок / внешний предкрылок
n) extension triple-slotted flap
15. носок крила, що відхиляється / отклоняющийся носок крыла
16. передкрилок / предкрылок
Exercise 36. Translate text 4 then divide the text into logical parts and write the key–note of each part in English.
Text 4. WingConstruction
The airplane wing does not consist of one single piece from one wing tip to the other, as the manufacture and assembly of such a wing is difficult. In addition, it is a difficult and costly business to replace a damaged part of such a wing. Usually the wing, like the fuselage, may be constructed in sections. They are: the center section (or center panel) which extends across the fuselage and projects outward at each side, and the outer main planes (or outer panels). The center panel may be an integral part of the fuselage or it may be a separate unit. When it is a separate unit it fits so snugly to the fuselage as if they are one unit. The outer panels are subdivided further into their respective components, such as main planes proper, ailerons, flaps and wing tips. The wing tips are small units bolted to the outer end of the outboard panel. This construction provides an easy method of correcting damage.
The aileron construction is similar to the wing construction. The wing flaps are large airfoils hinged to the trailing edge of the wing. There are four types of flaps: plain flaps, split trailing edge flaps, slotted flaps, and Fowler flaps.
The plain flap when in neutral position appears almost to be a part of the wing itself, but its hinge permits it to move downward as desired.
In the split trailing edge type, the lower half of the wing can deflect downward. The upper part of the trailing edge of the wing may deflect upward to increase the drag, without increasing the lift. With the slotted flaps the entire rear part of the airfoil can deflect downward.
The Fowler flap is an arrangement by which the lower part of the trailing edge of the wing rolls back on a track. This movement increases the effective width of the wing.
The wings may have slots. Slots are passages through the airfoil near the leading edge. These slots help to maintain proper flow of air above the wings, and this permits the aeroplane to fly at a higher angle of attack. Movable parts of the leading edge of the wing for increasing lift at low airplane speeds are called slats.
Exercise 37. Find English equivalents of the following word combinations in text 4.
Одна суцільна частина / одна цельная часть; виготовлення та монтаж / изготовление и монтаж; замінити пошкоджену частину / заменить поврежденную часть; центроплан / центроплан; простягатися через фюзеляж / простираться через фюзеляж; виступати зовні / выступать наружу; невід’ємна частина / неотъемлемая часть; окрема частина / отдельная часть; відповідні компоненти / соответствующие компоненты; велика аеродинамічна поверхня / большая аэродинамическая поверхность; рухатися в бажаному напрямку / двигаться в необходимом направлении; нижня половина крила/нижняя половина крыла; без збільшення підіймальної сили / без увеличения подъемной силы; уся задня частина профілю / вся задняя часть профиля; пристрій / устройство; відкочуватися назад по напрямним рейках / откатываться назад по направляющим; ефективна ширина крила / эффективная ширина крыла; щілина в передній кромці аеродинамічного профілю / щель в передней кромке аэродинамического профиля; підтримувати потік повітря / поддерживать поток воздуха; потік над крилом / поток над крылом; передкрилок / предкрылок.
Exercise 38. Fill in the gaps with the terms: separate,flaps, one single piece, slats, passages, an integral part, construction, tip.
1. The airplane wing does not consist of … from one wing … to the other. 2. The center panel may be … of the fuselage or it may be a … unit. 3. The outer panels are subdivided into main planes proper, ailerons, … and wing tips. 4. The aileron construction is similar to the wing … 5. Slots are … through the airfoil near the leading edge. 6. … are movable parts of the leading edge of the wing.
Exercise 39. Answer the questions on text 4.
1. Why doesn’t the airplane wing consist of one single piece?
2. What are three main sections of the wing? 3. What wing section extends across the fuselage? 4. What respective components are the outer panels subdivided into? 5. What are wing tips? 6. What is aileron construction similar to? 7. What are flaps hinged to? 8. What are four types of flaps mentioned in the text? 9. What are wing slats?
Exercise 40. Write out adjectives in comparative and superlative degrees. Comment on their structure. Translate the sentences.
A. 1. Airplanes, helicopters and glider are heavier-than-air craft. 2. The newest aircraft features a larger, thicker cross-section, virtually all-composite wing fitted with larger ailerons and flaps. 3. The new wing has a thicker, supercritical aerofoil section. 4. This section, with larger slotted flaps and ailerons, provides shorter take-off performance. 5. The advanced wing section makes it possible to design a wing of greater span for a given weight providing more internal volume for fuel. 6. It became clear that expendable launchers were the quickest and also the cheapest way of accomplishing most of the set objectives. 7. The newly developed fighter will cruise at much higher speeds without running out of fuel and will carry heavier payloads. 8. The obtained experimental results indicate that the winged missile should provide the highest manoeuvrability over a larger operating range.
B. 1. The thick section and increased area of the wing enable 50 per cent more fuel to be carried internally, giving a better radius of action without external tanks. 2. But at the same time this construction produces more considerable drag and, with higher operating weights the speed of the new models is lower than that of its predecessor. 3. The more complex control system in large turbojet aircraft is far more sophisticated than the type employed in lighter airplanes. 4. One of the simplest yet most important devices to aid the pilot of an aircraft are trim tabs attached to the control surfaces.
Exercise 41.Form the degrees of comparison of the following adjectives.
Exercise 42. Find antonyms among the words of exercise 41.
Exercise 43 .Speak on “Wing structure.”
Exercise 44. Translate text 5 in a written form.
Text 5. How an Airplane Flies The shape of a wing determines how it will perform in a stream of air. A flat shape fights air flow, causing drag (resistance). A curved shape allows air to flow smoothly around it.
The upper side of the wing is curved and the lower side is straight or almost straight. The propeller pulls the airplane at high speed through the air.
A wing that is curved on top and flatter on the bottom creates lift. The air passing over the top surface has a longer distance to travel and therefore moves more quickly creating less pressure than the slower air flowing below the wing. The air below the wing exerts pressure upward, causing lift.
When air flowing over the top surface of a wing is faster than the air running on the bottom surface, the pressure on top is lowered. The greater pressure from below propels the wing up into the low pressure area, creating lift.
If the wing is tilted upward (when the nose of the plane points up), lift increases. But too steep a tilt causes wing stall or a complete loss of lift.
Exercise 45. Find in text 5 adjectives in the comparative degree (7).
Exercise 46. Answer the key-questions on text 5.
1. What wing shape creates lift? 2. What propels the wing up? 3. What may cause a complete loss of lift?
Exercise 47. Write a summary of text 5.
Exercise 48. Put the verbs in brackets into the proper form of present or past continuous tense.
1. This car (make) a very strange noise. – Do you think it is all right? 2. The plane that you (look) for now (leave) for London an hour ago. 3. This airplane (go) to take off or to land? 4. You (wait) for the shop to open? 5. Last year the planes (land) and (take off) from separate runways one after another. 6. You (fix) a leading edge flap now? 7. Movable airfoils (change) the attitude and direction of flight. 8. – Where is the pilot? - He must (fill) the log book after landing. 9. The aeroplane in which the football team (travel) made a forced landing at the alternative airfield. 10. They took off the wheel of the car and (mend) the puncture. 11. The exam had jut begun and the candidates (write) their names at the top of their papers. 12. They said the car (travel) at 60 m.p.h when it began to skid.
Exercise 49. Match English-Ukrainian/Russian equivalents.
14. стрілоподібдне крило з перемінною стрілоподібністю / стреловидное крыло с переменной стреловидностью
n) tapered wing
15. стрілоподібне крило з прямою стріло-подібністю / стреловидное крыло с прямой стреловидностью
o) inboard engine
Exercise 52. Translate text 6 without a dictionary and give the gist of it.
Text 6. Man's desire to fly
The desire to fly was one of the oldest desires of man. But in old times people knew little about air. They did not know that life could not exist without it.
People began to study that phenomenon. Some scientists began to ask "What is air and how can a man fly in it?"
The Greek philosopher Aristotle believed that air had weight and pressed on bodies which were in the air. Later men of science like Galileo, Roger Bacon and Pascal came to the conclusion that air was a gas and that the higher you went the less its pressure was. That human flight is possible is the fundamental idea of the book by Leonardo da Vinci. In the book the famous Italian artist and scientist recorded the first scientific principles of human flight. He found that the faster the flow of air, the greater the lift was. As a result of these studies he designed a flying device. In his device the pilot had to operate movable wings with the help of his arms and feet. But the machine did not fly.
In the course of many centuries scientists tried to make a flying device. But the development of a practical flying device on a really scientific basis began later. The first flying machine a man could control in the air appeared only in the 19th century.
Exercise 53. Write out the comparative constructions “the… the…” from text 6.
Exercise 54. Read text 7 and put key questions to it.
Text 7. A 330 / A 340 Common Wing
The A 340 wing is virtually identical to that of the A 330. Its design represents a wing which can support either two or four engines. It meets the economic cruise requirements of both the medium-range A 330 and the long-range A 340.
The A 340 wing is the biggest to be designed and built by British Aerospace for the Airbus family. It has the highest sweep of any Airbus wing. Although similar in overall arrangement, the layout of leading-edge slats, trailing-edge flaps, spoilers and ailerons differs in details – mainly because of the engines. The ailerons are drooped for take off and landing and deflected upwards after touchdown to increase lift dumping and breaking efficiency.
The most obvious visual difference between the A 330 and A 340 wings is the latter’s outer engine installation.
Two years of intense three-dimensions computer analysis, coupled with windtunnel studies, has resulted in the A 340 having less wing/engine interference drag than the two-engined A 310.
Exercise 55. Write out adjectives in the superlative degree from text 7.
Exercise 56. Translate text 8 in a written form.
Text 8. Wings
All airplanes, by definition, have wings. Some are nearly all wing with a very small cockpit. Others have minimal wings, or wings that seem to be merely extensions of a blended, aerodynamic fuselage, such as the space shuttle. A delta-wing design derived from the shape of the Greek letter delta, merges the wing and tail of an aircraft into one large flying surface. The shape of the wing resembles an isosceles triangle1 and provides greater aerodynamic advantage in supersonic flight.
Before the 20th century, wings were made of wooden ribs and spars (or beams), covered with fabric that was sewn tightly and varnished to be extremely stiff. A conventional wing has one or more spars that run from one end of the wing to the other. Perpendicular to the spar are a series of ribs, which run from the front, or leading edge, to the rear, or trailing edge, of the wing. These are carefully constructed to shape the wing in a manner that determines its lifting properties. Wood and fabric wings often used spruce for the structure, because of that material's relatively light weight and high strength, and linen for the cloth covering.
isosceles triangle- рівнобедрений трикутник/ равнобедренный треугольник
Exercise 57. Speak on: