PRIMUS
r
1000 Integrated Avionics System
A28--1146--112--00
8-25
Modes of Operation
AD--50992@
RUNWAY
OUTER
MARKER
4.0--7.0 MILES
MIDDLE
MARKER
3500 FEET
RADIO ALTITUDE
BETWEEN 1200
AND 1500 FEET
RADIO ALTITUDE
BETWEEN 200
AND 300 FEET
ILS Approach Mode Tracking, Profile View
Figure 8--20
PITCH HOLD MODE
The pitch hold mode is the basic autopilot and flight director vertical
mode. This mode is best described by comparing the operation of the
pitch hold mode with the AP engaged and with the AP not engaged.
Pitch Hold Mode Operation, AP Engaged
Pitch hold mode with AP engaged operates as follows:
D
If no vertical FD modes are active, the AP holds the pitch attitude
that existed at the time the AP was engaged. The vertical flight
director mode is annunciated as PIT.
D
The pitch reference can be changed by pushing and holding the
TCS (touch control steering) button on the pilot’s or copilot’s control
wheel and manually flying the aircraft to a new pitch attitude
reference. When the TCS button is released, this new reference is
held by the autopilot. The pitch reference can also be changed by
moving the PITCH wheel on the autopilot controller.
Pitch Hold Mode Operation, AP Not Engaged
Pitch hold mode with AP not engaged operates as follows:
D
Selecting an FD lateral mode with no active FD vertical mode
displays the command bar. The command represents the aircraft
pitch attitude at the moment the FD lateral mode was selected. The
vertical flight director mode is annunciated as PIT.
D
The pitch hold mode is cancelled by manual or automatic selection
of any FD vertical mode.