Gulfstream IV - Failure Detection System

(c) On both the pilot’s and copilot’s display controllers,
simultaneously depress and hold the Sea Level (S/L) line
select key.
(d) Continue holding both S/L line select keys until the
normalized AOA indicator pointer slews to full scale and
observe the following:
• Stall warning (control column shaker) occurs between
0.70 and 0.80
• Stall barrier (control column pusher) occurs between
0.95 and 1.07
• Check that the BARR DISC button will override the
pusher
(e) On both the pilot’s and copilot’s display controllers,
simultaneously depress and hold the ALT line select key.
(f) Continue holding both ALT line select keys until the
normalized AOA indicator pointer slews to full scale and
observe the following:
• Stall warning (control column shaker) occurs between
0.54 and 0.65
• Stall barrier (control column pusher) occurs between
0.79 and 0.90
• Check that the BARR DISC button will override the
pusher
NOTE:
Both pilot’s and copilot’s sides have to be tested
simultaneously in order to activate the control column
pusher.
NOTE:
Another momentary push of the TEST function key
may be required to ensure the AOA indicator is in the
normal area prior to takeoff.
G. Failure Detection System:
CAA Certified Aircraft Only: A flight control automatic failure detection
system monitors flight control inputs from the control columns and
compares them to the elevator actuator outputs. If the system detects a
failure, it automatically shuts off hydraulic pressure to the actuator and
triggers the appropriate warning on the Crew Alerting System (CAS). Once
activated by a malfunction, hydraulic pressure is inhibited until power to the
respective monitoring system is interrupted, for instance, by pulling and
resetting the appropriate circuit breaker.
The monitoring system is a dual-channel system. One channel controls the
Combined hydraulic system pressure source while the other controls the
Flight hydraulic system pressure source. Power for the system is received
from the 28 VDC Essential DC bus.
A pair of limit switches monitor applied control column input while a pair of
OPERATING MANUAL
PRODUCTION AIRCRAFT SYSTEMS 2A-27-00
Page 13
January 31/02
Revision 6