Text 1. Ice Protection System

The aircraft ice protection system provides flight safety under king conditions when flying at any altitude and speed irrespective of duration of flight.

Protected from ice formation in the aircraft are:

- Wing and tail empennage;

- Propeller blades and spinners;

- Engine air intakes;

- Four forward glass panels of the cockpit wind-screen.

The principle of operation of all the anti-icers is based on the fact that with the anti-icers put into operation the temperature of protected surfaces reaches a positive value thus preventing formation of ice on them and providing remove of the ice formed.

When the air intake anti-icers are operating the power to them is supplied continuously. The power to the windscreen anti-icers operative is supplied so that the temperature of the outside surface of the windscreen glass panels does not exceed + 35°C. In operation the wing, tail empennage and propeller heaters receive power periodically in a repeating cycle The cycle consist of a heating period when the protected surface is heated up to a positive temperature and the ice formation (if present) is removed, and a cooling period when the protected surface can be cooled up to a negative temperature and the ice begins forming again.

As compared with the continuous heating the electric cyclic method of ice protection reduces the power consumption by several times. It is explained by the fact that in the second case the current is supplied to the de-icer periodically, and a light layer of ice forming on the protected surface during cooling period does not affect the aerodynamic characteristics of the aircraft but sharply reduces the heat loss due to the ram air flow.

Exercise 3. Translate word combinations with the term ice.

Ice formation, ice layer, ice protection, ice prevention, ice warning, ice control panel, windscreen ice, wing ice; to detect ice, to remove ice, to warn about ice

Exercise 4. Give the Ukraine or Russia equivalents for the following word combinations.

Ice protection system, windscreen glass panel, propeller heaters, wing heaters, tail empennage heaters, windscreen anti-icers, wing anti-icers.

Exercise 5. Translate the following words used both as verbs and nouns.

To form – formation, to detect – detection, to protect – protection, to serve – serve, to remove – remove, to heat – heat.

Exercise 6. Match the equivalents.

heat loss передние стеклянные панели

repeating cycle условия

protected surfaces высота

altitude длительность

forward glass panel образование

reduce защищаемые поверхности

positive value положительные показания

duration превышать

conditions повторяющийся цикл

formation слой

exceed снижать

layer теплопотеря

Exercise 7. Complete the following sentences.

1.The aircraft ice protection system provides ___________. 2. The ice protection system provides protection for ___________. 3. The principle of operation of ice protection system is to supply__________. 4. When anti-icers are operated the protected surfaces temperature _________. 5. The positive value of temperature prevents___________. 6. The air intakes and windscreen are heated __________. 7. The temperature of the outside surface of windscreen glass panel __________. 8. The wing, tail empennage, propeller heaters are supplied by __________. 9. The power consumption is the advantage of ____________. 10. During the electric cycle method aircraft reuses _________.

Exercise 13. Answer the questions on text 1.

1. What does the ice protection system provide? 2. What units does the ice protection system protect? 3. How does the ice protection system operate? 4.Why should the temperature of protected surfaces reach a positive value? 5.What are happing with protected surfaces while anti-icers are operating? 6. What are the two types of ice protection? 7. How is the power to windscreen supplied? 8. How is the power to wing, tail empennage, propeller heaters supplied? 9. What are the periods of periodically supplying power? 10. What is the advantage of heating the electric cycle method?

Exercise 8. Memorize new words and use them to translate text 2.

amber light – индикаторы янтарного цвета

switch - включатель

anti-ice valve – кран для впуска горячего воздуха в противообледенительную систему

outboard leading edge - пердкрылки