Heading Indicator
Heading indicator or HI is the instrument that shows us the direction of the nose of the aircraft. It’s a gyroscopic instrument operated in vacuum. While it is very similar to the magnetic compass , a significantly different is that it does not rely on the magnetic field of the earth, but as like gyroscopes, it remains fixed in space, such as a spinning top that keeps on turning regardless of whether changing the slope of the level at which rotates.
So Heading Indicator continues to show us the right direction of the plane, without being influenced by the shifting or tilting that takes in all axes. The gyroscope rotates by electric motor, or by vacuum pump in the engine of the plane.
Due to the rotation of the earth ( 15 degrees every hour) and variations of the instrument from the friction and loss of balance, a correction needed periodically with the aid of the compass. This should be done every 15 minutes during the flight.
For FlightSimmer.GR
Giannis Evagelinos
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