System Operating Modes; Pitch And Roll Attitude Hold (Pit) Modes; Altitude Hold (Alt) Mode - Honeywell Bendix/King KFC 225 Pilot's Manual

System Operation

System Operating Modes

ARM VS
YD
G
UP
P R
AP FD HDG NAV APR REV ALT DN
KFC 225
Pitch and Roll Attitude Hold
(PIT) Modes
The Pitch Attitude Hold (PIT)
mode allows constant attitude climbs
and descents. The AP or FD button
engages PIT mode.
To operate in the PIT mode
(with autopilot currently disengaged):
1. FD button - Press. Note ROL
and PIT are displayed. Pressing
the AP button will engage the
autopilot in ROL and PIT modes.
2. UP or DN button - Select
desired climb or descent attitude.
Each button stroke will increment
the pitch attitude by 0.5°. Pushing
and holding the UP or DN button
will cause the aircraft to pitch at
0.8° per second. Releasing the
button will sync the attitude to the
present pitch attitude.
To initiate a climb or descent from

Altitude Hold (ALT) mode:

1. ALT button - Press. Note ALT
changes to PIT referencing the
present pitch attitude.
2. UP or DN button - Select
desired climb or descent attitude.
Each button stroke will increment
the pitch attitude by 0.5°.
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KFC 225 AUTOMATIC FLIGHT CONTROL SYSTEM
The ROL mode engages in wings
level Roll Attitude Hold mode.
To change ROL Attitude Hold Mode:
1. Press CWS and bank the air-
craft to the desired bank angle. If
the bank angle is less than 6°
when the CWS button is released,
the autopilot will hold wings level.
If the bank angle is greater then 6°
when the CWS is released, the
autopilot will hold the bank angle
up to the maximum allowed by the
autopilot for that aircraft.
ARM VS
YD
G
UP
P R
AP FD HDG NAV APR REV ALT DN
KFC 225
Vertical Speed (VS) Mode
The Vertical Speed (VS) mode
allows vertical speed climbs and
descents. The VS button engages
vertical speed mode.
To operate in the VS mode (with
autopilot currently disengaged):
1. VS button - Press. Note ROL,
VS and current vertical speed is
displayed. Pressing the AP button
will engage the autopilot in ROL
and VS modes.
2. UP or DN button - Select
desired climb or descent rate.
Each button stroke will increment
the vertical speed commanded up
or down by 100 ft/min per button
press, or at the rate of approxi-
mately 300 ft/min per second if
held continuously.
Rev. 0
Apr/99
To initiate a climb or descent from
Altitude Hold (ALT) mode:
1. VS button - Press. Note ALT
changes to VS and current vertical
speed is displayed.
2. UP or DN button - Select
desired climb or descent rate.
Each button stroke will change the
vertical speed commanded up or
down by 100 ft/min per button
press, or at the rate of approxi-
mately 300 ft/min per second if
held continuously.
Note: VS command value will be dis-
played during Control Wheel
Steering (CWS) and for three sec-
onds following VS engagement or
pressing the UP or DN button. Both
altitude and vertical speed utilize the
same display area. Altitude is always
displayed except during vertical
speed selection. If the VS command
value is not displayed, pressing (and
releasing) the UP or DN button will
not change the indicated altitude ref-
erence but will display the VS com-
mand value.
Note: When operating at or near the
best rate of climb airspeed, at climb
power settings, and using vertical
speed hold, it is easy to decelerate
to an airspeed where continued
decreases in airspeed will result in a
reduced rate of climb. Continued
operation in vertical speed mode
can result in a stall. Pitch Attitude
Hold may provide better operation at
these airspeeds.
Rev. 0
KFC 225 AUTOMATIC FLIGHT CONTROL SYSTEM
Apr/99
System Operation
ARM VS
YD
G
UP
P R
AP FD HDG NAV APR REV ALT DN
KFC 225
Altitude Hold (ALT) Mode
The Altitude Hold (ALT) mode
maintains the pressure altitude
acquired upon selection of altitude
hold. The ALT button toggles
between altitude hold and pitch atti-
tude hold modes.
To operate in the ALT mode:
1. ALT button - Press. Note ALT
is annunciated and autopilot
maneuvers to maintain pressure
altitude acquired at button selec-
tion.
2. UP or DN button - Select to
change altitude. Button strokes will
move the reference altitude by 20
feet per press, or if held continu-
ously will command a 500 ft/min
altitude change, acquiring a new
reference altitude upon button
release.
Note: The system incorporates auto-
matic Baro correction capability. Any
change in Baro setting will be com-
pensated for by the autopilot to con-
tinue holding the reference altitude.
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