Chapter 2 - Artificial Horizons

Question 1

Describe the gimbal pivots of the self-contained artificial horizon?

Answer 1

Outer gimbal - along the longitudinal axis
Inner gimbal - along the lateral axis

Question 2

An artificial horizon is which type of gyro?

Answer 2

Vertical gyro

Question 3

In an artificial horizon, what is the purpose of the actuating pin?

Answer 3

Acts as a fulcrum point, so that as the aircraft climbs, the actuating pin pushes the horizon bar down below the ‘gulls wings’

Question 4

How does the pointer indicate the degree of roll in an artificial horizon?

Answer 4

It is fixed with the gyro so that as the aircraft and scale move around the longitudinal axis, the degrees of bank are indicated

Question 5

In a pneumatic gyro, how does the rotor spin?

Answer 5

Air issuing from jets impinges on rotor buckets, imparting an even driving force to spin the rotor

Question 6

How is an erection (levelling) system provided in a pneumatic gyro?

Answer 6

At the bottom of the gyro there are four vanes 90° to each other

When the gyro is erect, all four vanes are open

When the gyro moves away from the correct position, one of the vanes will close, causing a reaction, which will precess the gyro back to the erect position

Question 7

What will be the slip of a squirrel cage induction motor supplied with 115 volt, 3 phase 400 Hz AC as an electrical artificial horizon, and what RPM will this equate to?

Answer 7

6%

RPM - 22,500