加拿习加国学习6.08heading indicator

1、Section 6.8Heading IndicatorHeading IndicatorLesson ObjectivesPrinciples of OperationComponentsPower SourcesErrorsLimitationsServiceability ChecksPrinciples of OperationThe Heading Indicator (H.I.) AKA “directional gyro”, indicates the heading of the aircraft.The H.I. is set to the magnetic compass

2、as a reference but does not have the reading difficulties associated with the magnetic compass.It uses the principle of Rigidity in Space.Gyro is gimbaled with one degree of freedom - yawThe spin axis is horizontal.The plane of rotation is vertical.Gyro remain fixed in space while the a/c rotates ar

3、ound it.A compass card is fixed to the gyro.Older types used a drum while newer ones use a compass rose display.Heading IndicatorPower SourcesThe heading indicator is almost always powered by the vacuum system.Electric gyros are not very common.LimitsThe heading indicator does have some operational

4、limits:55 degrees pitch and bank in older types85 degrees pitch and bank in newer types.Some types are fully aerobatic with 360 degrees in pitch and bank.If limits are exceeded, gyro may topple.ErrorsPrecession due to frictionApparent drift due to the earths rotation.Must set the H.I. to the magneti

5、c compass every 15 minutes. (unless you have a “slaved gyro”)Erection mechanism keeps the gyro level using an air blast from nozzles.H.I. Erection MechanismServiceability ChecksCheck the H.I. indicates properly doing left and right turns while taxiing.Allow the gyro to reach normal operating speed (5 minutes for vacuum, and 3 min for electric)Che