minimum (such as a wing tip). This sensor converts magnetic energy to an electrical
voltage, which then drives electrical motors that turn the compass card to reflect changes
in aircraft heading (see Figure 4.1-3).
Figure 4.1-3 Remote Gyro Vertical Compass Card
Because the compass is gyro-stabilized, it is not subject to "G-loading" and continues to
function in high-G environments. The aircraft's magnetic heading is found under the white
triangle at the top of the card.
As a backup to the primary system, all aircraft have a Stand-by Compass (see Figure 4.1-
4). This is a direct reading compass in which the measurement of direction is taken directly
from a balanced/pivoted magnetic needle. The stand-by compass is sometimes called the
"wet" compass because it is filled with a fluid to dampen needle movement. This compass
is unstable during maneuvering, but it has the advantage of reliability and is independent of
the aircraft's electrical system.