King Air C90GTi, Pilot Training Manual

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KING AIR C90GTi/C90GTx PILOT TRAINING MANUAL
The formation of ice at the transducer
vane, or on the wing leading edge, re-
sults in erroneous indications in flight
The airspeed tape on the PFDs incorporates
an Impending Stall Speed/Low Speed Cue
(ISS/LSC) to visually indicate when the air-
speed is nearing AFM published stall speeds..
It has no connection or input from the stall
warning transducer vane. See the Airspeed
Display section of the PFD earlier in this chap-
ter.
FLIGHT GUIDANCE
SYSTEM (FGS)
The Flight Guidance System (FGS) consists of
an integrated flight director (FD) and autopi-
lot (AP) system. It includes yaw damping and
pitch trim functions. The Flight Guidance
Panel (FGP), the SYNC and YD/AP DISC
buttons are on the control wheels, with the GA
button on the left power lever. These inputs
control the FGS .
The FGS consists of two flight guidance chan-
nels with independent computers, related
hardware, and control circuits. This provides
independent output for flight director and au-
topilot functions. AP/FD indications are dis-
played along the top of the PFDs (Figure
16-61). Active modes are displayed in green
and armed modes are displayed in white,
below the active modes.
Figure 16-61. Flight Guidance System
Display
FLIGHT GUIDANCE
COMPUTERS (FGC)
Each FGC is supplied with input from the
AHRS, navigation data, FGP selections, servo,
and ADC computers. The coupled FGC pro-
duces control signals for yaw damping,
AP/FD, and pitch trim functions. Each FGC is
supplied data from the onside ADC, EFIS,
and AHRS. The autopilot and flight director
require both attitude portions of the AHRS
to be operational.
Each FGC produces an independent AP con-
trol signal. Only one FGC may be coupled to
the autopilot at any time. AP control compu-
tations from the other FGC are continuously
compared with AP control signals from the
coupled FGC. The autopilot automatically dis-
engages when autopilot control discrepancies
are detected.
FLIGHT GUIDANCE PANEL (FGP)
The Flight Guidance Panel (FGP) controls
both FGC’s. The coupled FGC then controls
the Flight Guidance System (Figure 16-62).
The FGP is centered at the top of the instru-
ment panel. All AP/FD mode selections are
made on this panel.
The FGP has the following controls:
AP Button
The AP button controls autopilot engagement.
The autopilot engages if the following condi-
tions are met: (1) YD/AP DISC switch-bar is
raised; (2) no unusual attitudes/rates exist; (3)
and the flight guidance computer does not de-
tect any autopilot faults. The yaw damper is
automatically engaged when the AP button is
pushed.
Collins
20
HDG PTCH
ALTS
14
000
4
<
140
80
6935
FMS
AP
V
WARNING
16-31
FOR TRAINING PURPOSES ONLY
16
A
VIONICS