Although attitude indicators (fig. 6-38)
Some attitude indicators have a self-contained
differ in size and appearance, they all have
gyro. Other more modern indicators use pitch and
roll information from the inertial system or the
the same basic components and present the
same basic information. There will always
attitude heading reference system. These systems
be a miniature aircraft on the face of the
are accurate and reliable. They gain their relia-
indicator that represents the nose (pitch) and
bility and accuracy from being larger since size
wing (bank) attitude of the aircraft. The bank
is not limited by the space of an instrument panel.
Electrical signals from the remote gyro travel via
pointer on the indicator face shows the degree of
synchros. The signal is amplified in the indicator
bank (in 10-degree increments up to 30 degrees,
to drive servomotors and position the indicator
then in 30-degree increments to 90 degrees). The
sphere is always light on the upper half and dark
sphere. This positioning is exactly as the vertical
gyro position in the gyro case. In the newer
on the lower half to show the difference between
attitude indicators, the sphere is gimbal-mounted
sky and ground. Calibration marks on the
and capable of 360-degree rotation. In contrast,
sphere show degrees of pitch in 5- or 10-degree
the older gyros could only travel 60 degrees to 70
increments. Each indicator has a pitch trim
adjustment for the pilot to center the horizon as
degrees of pitch and 100 degrees to 110 degrees
necessary.
of roll. Some aircraft incorporate an all-attitude
Figure 6-38.-Roll and pitch indications on the attitude indicator.
6-32
