曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
rudder pedal effort and response time to inputs are increased while in
manual reversion, the aircraft remains capable of positive and harmonious
control.
E. Rudder Load Limiting System:
(See Figure 12.)
Load-limiting (force-modulating) valves inside the rudder actuator restrict
Combined and Flight hydraulic system pressure to prevent vertical
stabilizer structural overload. Surface movement is limited by these valves
when higher airspeeds increase the airloads imposed against the rudder.
When the hinge moment limit is reached, the force-modulating shift,
reducing pressure to a maximum of approximately 2,250 psi, regardless of
hydraulic system pressure. Operation of either valve to restrict hydraulic
pressure closes an internal microswitch that triggers a blue RUDDER
LIMIT advisory CAS message. With the RUDDER LIMIT message
displayed, further displacement of the rudder surface is inhibited.
When on the ground with the Combined hydraulic system operating, rudder
actuator load limiting can be checked by applying gradual input force to the
rudder pedals until the rudder surface is bottomed against its stops (left or
right). The RUDDER LIMIT advisory CAS message will be displayed at the
instant of pressure limiting within the actuator. Flight crews are cautioned
that both the gust lock and nose wheel steering must be OFF before
performing this test. Also, it should be noted that if performing this test with
only the Flight hydraulic system operating, the RUDDER LIMIT message
may or may not be displayed.
OPERATING MANUAL
2A-27-00 PRODUCTION AIRCRAFT SYSTEMS
Page 32
October 11/02
Revision 8
In the event of a malfunction or failure of internal rudder actuator load
limiting, redundant limiting is provided by an additional external load
limiting valve installed upstream of the rudder actuator. With this
configuration, continuous rudder load limiting is afforded as either load
limiting valve (internal or external) will limit output pressure. The external
load limiting valve limits total hydraulic pressure to a maximum of 2,650
(Combined and Flight systems) to the rudder actuator.
The external load limiting valve is checked by observing CAS for display of
an amber SNGL RUDDER LIMIT caution message. Proper operation of the
valve is indicated by display of the message during the following sequence:
• Before starting engines (power on) — message displayed
• Right engine only operating — message displayed
• Both engines operating — message not displayed
Proper operation of the valve can also be verified during the following
sequence:
• 0 psi Combined pressure / 3,000 psi Flight pressure — message
displayed
• 3,000 psi Combined pressure / 3,000 psi Flight pressure —
message not displayed
• 3,000 psi Combined pressure / 0 psi Flight pressure — message not
displayed
F. Yaw Damper System:
A series mode yaw damper is incorporated into the rudder actuator.
Controlled by the autopilot, the yaw damper provides stability
augmentation by automatically counteracting any dutch roll tendency within
the aircraft. The system is referred to as a series mode system in that no
feedback is provided through the rudder pedals.
The yaw damper system consists of a solenoid-operated shutoff valve,
transfer valve, servo ram and summing lever / transducer. Electrical power
is supplied to the system through the Right Main and Essential 28 VDC
buses. Hydraulic power is supplied to the system by the Flight hydraulic
system only.
Located on the pilot’s flight panel, the YAW DAMP ENG / DISENG switch
engages or disengages the yaw damper. With the yaw damper engaged
(amber DISEN switch legend extinguished), 28 VDC power energizes the
solenoid-operated shutoff valve to the open position. Flight hydraulic
system pressure then flows to the transfer valve. Hydraulic pressure flow
and volume through the transfer valve is controlled by the torque motor
using a jet pipe / receiver pipe arrangement. The yaw damper / pitch trim
control panel is shown in Figure 9.
Depending on commands provided by the autopilot, the torque motor
positions a jet pipe to direct hydraulic pressure to two receiver pipes inside
the transfer valve. If equal commands are sent by the autopilot, the jet pipe
remains in a centered, or null, position. When unequal commands are sent,
the torque motor deflects the jet pipe in the necessary direction to supply
more pressure to one receiver pipe than the other. This shifts the transfer
valve spool and hydraulic pressure flows from the transfer valve to the
servo ram.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
湾流4操作手册 Gulfstream IV Operating Manual 2(15)
