3-28. AUTOMATIC FLIGHT CONTROL SYSTEM.
The AP-106 is an integrated
autopilot/flight director system that provides the following:
glideslope capture and track
Altitude hold mode.
Back course localizer mode.
Synchronized control wheel steering.
Indicated airspeed hold mode.
All-angle adaptive capture for VOR, LOC,
and LOC B/C.
Mode selection indicators.
Elevator trim indicator.
System integrity warning flags.
Automatic yaw damping.
Turn and slip indicator.
The flight director and autopilot have a common
computer system. When the autopilot is engaged, the flight
control system controls the aircraft and the pilot monitors the
flight path by observing the information displayed on the
pilot's flight director indicator (FDI) and the pilot's horizontal
situation indicator (HSI) (flight director system components).
Autopilot/flight director commands are selected at the
autopilot mode selector panel (fig.320), located on the
instrument panel (fig. 2-30). Manual roll rate and pitch
commands are inserted at the autopilot pitch-turn panel (fig.
Autopilot operational status is indicated by the
autopilot/flight director annunciator (fig. 3-22) positioned
above the pilot's flight director indicator on the instrument
panel (fig. 2-30). Two autopilot switches are also provided
on each control wheel (fig. 2-18). One switch is placarded
PITCH SYNC & CWS (pitch synchronize and control wheel
steering), and the other is placarded DISC-TRIM-AP-YD
(disconnect trim/autopilot/ yaw damp).
The automatic flight control system is protected by a
10-ampere circuit breaker, placarded AP PWR, located on the
overhead circuit breaker panel (fig. 2-27).
Controls/Indicators and Functions. The following
controls and indicators are provided for operation of the
Autopilot mode selector control panel (fig. 320). The
autopilot/flight director commands are selected by ,the
autopilot mode selector control panel, located on the
instrument panel (fig. 2-30). Selection is accomplished by
pressing the face of the appropriate push-on/push-off
annunciator switches. The lateral modes are HDG, NAV,
APPR and B/C. When not in a lateral mode, the flight
director command bars are biased out of view. The vertical
modes are ALT hold, and IAS hold. If a vertical mode is not
selected, the pitch hold mode is automatically operational.
Selection of a mode causes the legend of that annunciator on
the autopilot mode selector control panel to illuminate. The
self-test switch on the autopilot mode selector control panel
acts as a light test switch when depressed. For operation at
night, overall illumination of the autopilot mode selector
control panel and annunciator panel lights are adjusted by the
PILOT INST LIGHTS light control, located on the overhead
control panel (fig. 2-12).
Engages heading mode.
Commands aircraft to acquire the heading indicated by
heading marker on pilot's HSI.
NAV switch. Engages navigation mode. With
VOR 1, VOR 2 or TACAN selected, commands aircraft to
intercept and track VOR radial selected by course knob on
pilot's HSI. With INS selected, commands aircraft to track
steering signals from INS system. Intercept of approximately
45° and tracking will be computed by the INS system.
APPR cannot be selected with INS
APPR switch. Engages approach mode.
Commands aircraft to intercept and track ILS or localizer