TM 55-1510-220-10
Figure 3-20. Autopilot Mode &elector Panel (614E-42A)
(4)
ALT switch. Engages altitude hold mode.
Commands aircraft to maintain its pressure altitude.
(5)
IAS switch. Engages indicated airspeed hold
mode. Commands aircraft to maintain its indicated airspeed.
(6)
B/C switch. Engages backcourse mode.
Commands aircraft to intercept localizer back course.
Disables glideslope track.
(7)
ENG-DIS switch. Controls coupling of the
automatic pilot.
(a)
ENG.
Engages
autopilot
and
illuminates AP ENG annunciator light on autopilot/ flight
director annunciator panel (fig. 3-22).
(b)
DIS.
Disengages
autopilot
and
illuminates AP DISC annunciator light on autopilot/flight
director annunciator panel (fig. 3-22).
(8)
TRIM UP indicator. Illuminates when
autopilot is driving trim servo in up direction.
(9)
TRIM DN indicator. Illuminates when
autopilot is driving trim servo in down direction.
(10)
Self-test switch. Tests display and selector
indicator circuits when depressed.
(11)
Autopilot trim test switch (fig. 3-20).
Simulates trim system malfunctions and illuminates AP
TRIM FAIL warning annunciator light (fig. 230)
(12)
AIL HI TORQUE annunciator (fig. 321).
Illumination is automatic from ground to 10,000 feet to show
aileron servo is set to operate in high torque mode. Light
extinguishes automatically above 10,000 feet to indicate
aileron servo has terminated high torque mode operation.
(13)
TEST switch (fig. 3-21). Normally off. Used
only below 10,000 feet (TEST position) to confirm operability
of aileron servo.
c.
Autopilot/flight director annunciator panel (fig. 3-
22).
(1)
Description. The autopilot/flight director
incorporates its own annunciator panel located just above the
flight director display on the instrument panel (fig. 2-30).
The modes and indications given on the annunciator panel
are placarded on the face of the lenses and illuminate when
the respective conditions are indicated. Dimming of the
annunciator panel lights is provided by a control knob
adjacent to the panel placarded DIM BRT.
Change 2
3-38
