force is equivalent to 30 percent of stick
altitude are selectable on the AFCS CONTROL
panel. Longitudinal and lateral ground speed can
displacement. The maneuvering stability feature
is engaged whenever the AUTO PLT PBS is
also be beeped 10 knots with the cyclic trim
illuminated.
switch about the ground speed selected on the
AFCS CONTROL panel, The hover coupler
AUTOMATIC APPROACH TO HOVER. --
mode can automatically engage at the termination
The DAFCS provides the capability to perform
of the automatic approach. Also, the pilot can
manually engage it when the aircraft is hovering
an automatic approach to a zero longitudinal and
with less than 5 knots longitudinal groundspeed.
any lateral ground speed selected on the LAT VEL
control knob. Also, the DAFCS can perform an
To do this, the pilot presses the APPR/HVR
automatic approach to any radar altitude selected
button on the AFCS CONTROL panel with SAS
on the HVR ALT control knob between 40 feet
2, TRIM, and AUTO PLT engaged. The hover
and 200 feet. If the HVR ALT is set below 40 feet,
coupler engages when the longitudinal ground
the approach will be made to 40 feet and then
speed is less than 5 knots if engaged manually.
continued to the HVR ALT setting when the
After engagement, the aircraft accelerates to the
mode is switched from APPR to HVR. The
longitudinal and lateral ground speeds selected on
automatic approach can start at any airspeed and
the AFCS CONTROL panel. Pressing and
altitude. The automatic approach is an outer loop
releasing the cyclic TRIM REL removes cyclic
trim switch inputs. This action returns the aircraft
only function, and it commands the aircraft to
decelerate or descend until meeting the approach
to the LONG VEL and LAT VEL settings on the
profile conditions. If the approach mode is
AFCS CONTROL panel. Because of Doppler
selected when aircraft conditions are below the
noise, short-term longitudinal and lateral ground
speed is obtained from integrated longitudinal and
approach profile, the DAFCS commands the
lateral inertial acceleration. Long-term correction
aircraft to decelerate. The aircraft will decelerate
is obtained from the Doppler sensor using a
at 1 knot) second while in the radar altitude hold
7-second filter.
mode until the approach conditions are met. If
the approach mode is selected when the aircraft
is above the approach profile, the DAFCS
AUTOMATIC DEPART. --The automatic
depart mode provides the capability to perform
commands the aircraft to descend. The descent
occurs at 360 feet/minute when the aircraft is
an automatic departure from a coupled hover or
more than 50 feet above the approach profile. It
from an automatic approach. This mode can take
occurs at 120 feet/minute when the aircraft is less
the aircraft to a cruise airspeed of 100 KIAS and
than 50 feet above the profile. During these
altitude of 500 feet. If the coupled hover or the
conditions, the DAFCS uses the radar altimeter
automatic approach feature is engaged, engage
until the approach profile conditions are met.
the automatic depart mode by depressing the
When the approach profile conditions are met,
hover depart button on the cyclic grip. Depressing
the aircraft simultaneously decelerates at 1
the DEPART PBS a second time disengages the
knot/second and descends at 120 feet/minute.
automatic depart mode, but it doesn't auto-
This profile is maintained until the aircraft attains
matically re-engage the RAD ALT hold. Depress-
1 knot of Doppler ground speed and comes to
ing the hover depart button a second time
within 1 foot of the selected radar altitude. If the
disengages the automatic depart mode and returns
selected altitude is below 40 feet, the aircraft flies
aircraft control to the pilot. Upon engagement,
the aircraft accelerates at 2 knot/second and
to 40 feet and zero longitudinal ground speed and
then descends to the selected attitude. When
climbs at 480 feet/minute. During the departure,
ground speed equals 1 knot or less and the aircraft
the DAFCS computer monitors engine torque to
altitude is within 2 feet of the selected altitude,
ensure that it does not exceed 116 percent. At 100
KIAS, the airspeed hold automatically engages;
the hover coupler mode automatically engages.
The aircraft then accelerates to the selected
at a radar altitude of 500 feet, the radar altitude
longitudinal ground speed.
hold automatically engages. Any alternate cruise
airspeed or altitude condition of less than 100
HOVER COUPLER. --The hover coupler
KIAS and 500 feet is available to the pilot. The
provides longitudinal and lateral ground speed
pilot attains an alternate condition by depressing
control and stabilization about the selected ground
the cyclic trim release and collective trim release
speed and automatic altitude retention. The
at the desired airspeed and altitude, respectively.
If either trim release button is depressed and
longitudinal and lateral ground speed and the
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