Презентация, доклад по английскому языку

the speed of the aircraft

The airspeed indicator operates on the principle of differential pressure.Impact pressure from the pitot tube is transmitted into a diaphragm which is mounted in an airtight instrument case. Static pressure is vented to the instrument and therefore surrounds the diaphragm. When the airplane is motionless in still air, it has no airspeed because the impact pressure equals the static pressure, and the diaphragm is in equilibrium. When the airplane moves forward, impact pressure is greater than static pressure. This difference increases as the airplane's speed increases, and a corresponding distortion of the diaphragm takes place, The distortion of the diaphragm, being a measure of the differential pressure, is thus also a measure of the airspeed. The amount of distortion is registered by an indicating mechanism that is graduated in units of speed.