Page 777 - PPL-engelsk 2025
P. 777
Aircraft general knowledge
8.12.8.2 Turn indicator (turn indicator and turn coordinator)
The turn indicator shows movements of the aircraft around the vertical axis. This
instrument usually consists of two parts. A gyro part, which indicates a turn, and
a “balance indicator” which shows whether the turn has been carried out
coordinated.
The turn indicator is usually electrically powered (in contrast to the two other
gyro instruments (artificial horizon and heading gyro), which are usually vacuum
powered).
This ensures that if you lose power, you have the vacuum-powered gyros and
vice versa, if you lose vacuum, you have power to the turn indicator.
When moving in the plane of rotation, the gyro will react with a rotation around
the frame axis (precision).
The pointer will indicate the direction to which you are turning.
The size of the deviation depends on the speed of rotation.
If the right wing, for example, points to the white marking just above “R”, this
means that you are in a right turn, and that it is a standard turn of 180 degrees
in one minute.
This means that a full circle takes 2 minutes.
Below you can see the instrument
and on the right a schematic
diagram.
Flyveteori PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 777