Directional Gyro - Century 4000 Pilots Operating Manual

Autopilot
Heading Bug
Lubber Line
Miniature
Airplane
Compass
Card
Heading
Card Set
Selector
Knob (Push)
Knob (Push)

DIRECTIONAL GYRO

The Heading Selector DG replaces the standard directional gyro and provides a fully visible heading
indicator around the normal DG opening. The DG dial is marked in 5-degree intervals and numbered
each 30 degrees around its azimuth. A center index is provided at the top to align selected headings.
Additional indices are located each 45 degrees to facilitate rapid turn selection without mental arithmetic.
Any heading may be selected, either before or after engagement, and turns up to 180 degrees may be
programmed directly, either right or left. If the heading indicator is rotated beyond 180 degrees from the
DG card heading, the heading selector will command a reversal in bank to reach the resultant selected
heading in the shortest direction
The DG card is normally set to the magnetic compass with the card set knob on the left in the usual
fashion, while the heading selector indicator is rotated by the heading selector knob on the right. It will
still be necessary for the pilot to verify the compass card heading with the magnetic compass periodically.
Direction of rotation of both the knobs and indicator commands the same direction of turn.
NSD-360A, NSD-1000 AND
OTHER HEADING SYSTEMS
The Century 4000 autopilot may be optionally equipped with the Century Flight Systems, Inc. NSD-360A
or NSD-1000 HSI. The explanation which follows will be based on Century's HSI, however the principles
will apply equally to the heading systems of other manufacturers provided the differences in design,
features and concepts are ascertained and allowed for such as slaving, knob location, size, etc.
The NSD-360A and the NSD-1000 (Navigation Situation Display) are basically identical units except for
the gyro capsule. The 360A is an air driven gyro where as the 1000 is an electric gyro. The HSIs have
electrically servoed heading card driven by the information processed from the gyro capsule. Warning
flags and indicators include NAV flag, glideslope flag, TO/FROM meter and heading flag. Lateral radio
information is presented by the left/right meter and vertical radio information is presented by the
glideslope meter. Autopilot heading information is represented by positioning the heading bug to the
desired heading track.
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