grounding circuit to the two channels of the stick pusher computer. This puts the system into ice mode operation.
The AOA datums change by 8 degrees.
3.6
CAS Captions
3.6.1
PUSHER
The amber PUSHER caution message on the CAS display comes on and an aural gong is heard when one of
these conditions occur:
−
A failure of the stick pusher computer channel 1 or channel 2
−
When one channel is operating in normal mode and the other channel in ice mode
−
When the CAS detects ice mode conditions are present (inertial separation system is open with the propeller
deicing system on) but the stick pusher system stays in normal mode operation
−
A failure of the stick pusher servo (with 3 seconds delay)
−
When the PUSHER INTR switch is pushed (with 3 seconds delay)
−
A failure of any of the inputs from the AOA system, flaps, engine power or WOW switches
−
The g switch is active for longer than 3 seconds
−
When a failure is detected by the system Built-In-Test (BIT)
−
When the amber Air/Ground Fail caution message on the CAS display comes on.
3.6.2
Air/Ground Fail
The amber Air/Ground Fail caution message on the CAS display comes on and an aural gong is heard when there
is a difference between the LH and RH weight-on-wheel switches. When this occurs, the stick shaker and aural
stall warning are operational but the stick pusher is disabled.
3.6.3
Pusher Safe Mode
The cyan Pusher Safe Mode advisory message comes on if the stick pusher computer detects a flap position or
flap asymmetry greater than 2 degrees for 10 seconds or more. In safe mode, the stall warning trigger points are
rescheduled to operate at the 0 degrees flap position setting, irrespective of the flap position. The MAU gives a
signal to the CAS to display the Pusher caution message.
3.7
System Tests
The amber or green PUSHER ICE MODE caption on the CAS display comes on and stays on during system
pre-flight and in-flight tests.
3.7.1
System Start Up
When the electrical system is energized the amber PUSHER message on the CAS display comes on and stays on
until operation of the pre-flight test.
3.7.2
Pre-flight Test
The pre-flight test makes sure that the two channels of the stick pusher computer independently operate the stick
shaker actuator and the stall warning tone. Then, together, they operate the stick pusher servo. When the stick
pusher servo operates, the amber PUSHER message on the CAS display goes off.
The stick pusher computer must receive all of these signals to do the pre-flight test:
PC-12/47E AMM Doc No 02300, ISSUE 01 REVISION 26 MSN 545, 1001-1719,
1721-1999
12-B-AM-00-00-00-I
UNCLASSIFIED
Effectivity: All
12-B-22-20-00-00A-040A-A
UNCLASSIFIED
2021-12-04 Page 7
