Ap/Yd Annunciation; Control Wheel Trim Switch; Control Wheel Master Switch (Msw) - BOMBARDIER LEARJET 40 Pilot's Manual

Pilot's Manual

AP/YD Annunciation

At the very top center section of the PFDs is an area dedicated to flight
director and autopilot annunciations. A horizontal arrow appears at
the top center of each PFD between the flight director vertical and lat-
eral mode annunciators. This arrow points left or right, as selected on
the FGC XFR switch, to indicate which flight director the autopilot will
couple to when engaged. It also indicates which flight director has pri-
ority. Just below the arrow is a line reserved for autopilot and yaw
damper annunciation. A green AP and YD appear in this area when the
autopilot and/or the yaw damper is /are engaged.

Control Wheel Trim Switch

Manual primary pitch trim or roll trim commands are initiated by
pressing and holding of the arm switch and actuation of the control
wheel trim switch. Pressing and holding of the arm switch with control
wheel trim switch input will result in immediate autopilot disengage-
ment.
The yaw damper and flight director modes are not affected by manual
pitch or roll trim commands. Actuation of the control wheel trim switch
without pressing the arm switch allows manual autopilot commands.
During autopilot engagement, basic attitude commands (pitch and roll)
can be entered through either the pilot's or copilot's control wheel trim
switch (dependent upon which flight director is coupled to the autopi-
lot). With the autopilot engaged, activation of the control wheel trim
switch (without arm switch depressed), on the side coupled to the
autopilot, causes the flight director roll and/or pitch hold mode to be
activated.

Control Wheel Master Switch (MSW)

The MSW switch immediately disconnects all autopilot and yaw
damper servo drives. The selected flight director modes are not affect-
ed. In normal operation, a 28-vdc signal is routed through the normally
closed contacts of each MSW and then to the onside IC-600. This input
to the IC-600s is the autopilot disengage discrete, and if 28-vdc is re-
moved from this discrete on either IC-600, the autopilot will disengage.
5-70
PM-132A