Vayudoot Aviation

1. The spin axis of a directional gyro is maintained in ....... by means of ...... in an air driven gyro and by means of a ....... in an electrically driven gyro

the yawing plane; air jets; torque motor.

the horizontal plane; air jets; wedge plate.

the vertical plane; air jets; torque motor.

the yawing plane; air jets; wedge plate.

2. The purpose of the caging knob is

to reset the heading and to prevent toppling.

to prevent the gyro toppling.

to reset the heading.

to prevent apparent wander.

3. 15 sine latitude in degrees per hour increasing

acceleration error, turning error, altitude error, transport wander, rotor speed error.

transport wander, apparent wander, latitude error, turning error, acceleration error.

gimballing error, looping error, rolling error, rotor speed error, transport wander.

gimballing error, random wander, apparent wander, rotor speed error, transport wander.

4. Gimballing error

will be zero on only two headings during a 360 turn.

will disappear after a turn is completed.

will only occur during a 360 turn.

will remain until the gyro is reset.

5. The limits of pitch and roll for a modern directional gyro are respectively

55 and 85

85 and 55

55 and 55

85 and 85

6. The formula used to calculate apparent wander of a directional gyro in the northern hemisphere is

-15 sine latitude in degrees per hour.

+15 sine latitude in degrees for the time of running.

+15 sine latitude in degrees per hour.

15 sine latitude in degrees per hour increasing

7. A directional gyro indicator is basically a

horizontal axis tied gyro.

horizontal axis earth gyro.

vertical axis earth gyro.

vertical axis tied gyro.

8. In an air driven directional gyro the air jets are attached to

the instrument casing.

the outer gimbal.

the inner gimbal.

the rotor axis.

9. An air driven DGI is corrected for apparent wander at 56 N. If the aircraft is maintaining constant DGI readings

when flying north from 56 N the true heading of the aircraft will decrease

when flying south from 56 N the true heading will decrease.

when flying east from 56 N the true heading will decrease.

when flying west from 56 N the true heading will increase.

10. Apparent wander may be corrected in a DGI by

attaching a bias weight to the inner gimbal which makes the gyro precess in azimuth in the opposite direction to apparent wander.

causing the gyro to precess in a clockwise direction (in the northern hemisphere).

correcting wander by means of air jets.

attaching a bias weight to the inner gimbal which makes the gyro precess in azimuth in the same direction as apparent wander.

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Questions for DIRECTIONAL GYRO INDICATOR (DGI)