Fill in the diagram with missing information from the text
The text has 9 paragraphs. Which paragraph mentions a) different landing devices; b) vehicle flying due to up and down air streams; c) vehicle able to hover in the air?
Read the text again and decide if these statements are true or false. Correct the false ones.
1. Modern heavier-than-air aircraft are classified into two classes according to their flying principle.
2. Airplanes fly due to up and down air stream.
3. Gliders are equipped with airscrew and power plant.
4. Airplanes can be fitted with floats to take off and land on water.
5. In helicopters lifting force is produced by the wing itself.
6. The helicopters can take off and land vertically.
7. The autogiros and ballistic rockets fly on the same principles.
8. Ballistic rockets do not produce lifting force by means of a wing.
Ask your partner ten questions about types of aircraft.
5. Explain the difference between:
a) airplanes and ballistic rockets
b) helicopters and autogiros
c) seaplanes and amphibians
d) helicopters and airplanes
Vocabulary Focus
Match the synonyms.
A B
advance wing
produce mount
subdivide vehicle
propel progress
airfoil move
attach create
aircraft classify
Make up all possible combinations with the verbs.
To divide, to support, to produce, to propel, to attach, to place, to create, to equip, to differ, to require.
Make up 5 sentences with the word combinations from ex. 2.
Work in pairs. Give the definitions of the following words and expressions.
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Fuselage, glider, biplane, helicopter, amphibian aircraft, ballistic rocket, high wing monoplane.
5. Fill in the gaps with the words & expressions from the box.
wing position engines the autogiro the parasol wing flying boat seaplanes the wing itself a rotor ballistic rockets up and down airstreams |
1. Gliders are supported in the air by________.
2. The lifting force of the wing is created by ______ when it moves through the air.
3. The monoplanes are divided into four types according to________ .
4. ________ monoplane has its wing placed a short distance above the fuselage.
5. In _______ the boat hull replaces the airplane fuselage.
6. ________ are equipped with floats to take off water and land on water.
7. The helicopters produce lifting force by______.
8. ________ is equipped with a tractor airscrew and a rotor.
9. The rocket engine provides energy for propulsion for________.
10. In airplanes _____ supply power for forward motion.
Give the English equivalents to the words in the brackets.
1. Modern (летательные аппараты тяжелее воздуха) are divided into two classes according to the principle of flying.
2. The (планер) is lighter than the airplane.
3. Many airplanes are equipped (взлетать) from water and (садиться) on water.
4. At present (ЛА с вертикальным взлётом-посадкой) and (ЛА с укороченным взлётом-посадкой) aircraft are becoming popular.
5. The helicopter has a (фюзеляж) but there is no (обычный винт).
6. Helicopters have a few (недостатки).
7. Ballistic rockets do not require any lifting force produced (при помощи)
a wing.
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8. The power developed by the autogiro (двигатель) is (передавать) to the (воздушный винт).
Writing
Translate the text in a written form.
A "glider" is an unpowered aircraft. The most common types of glider are today used for sporting purposes. The design of these types enables them to climb using rising air. This has created the sport of gliding. Although many gliders do not have engines, there are some that use engines occasionally.
Early gliders had no cockpit and the pilot sat on a small seat located just ahead of the wing. They were usually launched from the tops of hills, though they are also capable of short hops across the ground while being towed behind a vehicle. To enable gliders to soar more effectively, the designers minimized drag. Gliders now have very smooth, narrow fuselages and very long, narrow wings with a high aspect ratio.
The early gliders were made mainly of wood with metal fastenings, struts and control cables. New materials such as carbon-fiber, glass-fiber and Kevlar have since been used with computer-aided design to increase performance. Drag has also been minimized by more aerodynamic shapes and retractable undercarriages.
With each generation of materials and with the improvements in aerodynamics, the performance of gliders has increased. One measure of performance is the glide ratio. A ratio of 30:1 means that in smooth air a glider can travel forward 30 meters while only losing 1 meter of altitude.
Due to the critical role that aerodynamic efficiency plays in the performance of a glider, gliders often have state-of-the-art aerodynamic features. The wings of a modern glider have specially designed low-drag airfoil. After the wings' surfaces have been shaped by a mold to great accuracy, they are then highly polished. Vertical winglets at the ends of the wings are computer-designed to decrease drag and improve handling performance. Turbulator devices in the form of a zig-zag tape are used to direct laminar flow air into turbulent flow at a desired location on the wing. This flow control prevents the formation of laminar flow bubbles and ensures the absolute minimum drag. Bug-wipers may be installed to wipe the wings while in flight and remove insects that are disturbing the smooth flow of air over the wing.
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Modern competition gliders are also designed to carry jettisonable water ballast (in the wings and sometimes in the vertical stabiliser). The extra weight provided by the water ballast is advantageous if the lift is likely to be strong, and may also be used to adjust the glider's center of mass. To avoid undue stress on the airframe, gliders must jettison any water ballast before landing.
Pilots can land accurately by controlling their rate of descent using spoilers, also known as air brakes. These are metal devices which extend from either the upper-wing surface or from both upper and lower surfaces, thereby destroying some lift and creating additional drag. A wheel-brake also enables a glider to be stopped after touchdown, which is particularly important in a short runway.
UNIT 5
AIRPLANE COMPONENTS
Preparing to Read
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