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
valves on the engine and left and right emergency pressurization
valves in the bleed air ducting. Each BLEED AIR switch has three positions:
EMER,ON, and OFF. When aBLEEDAIRswitch is in theONposition,
the respective bleed-air shutoff/pressure regulator valve will
open and the emergency pressurization valve will remain closed unless
the 9500-foot emergency pressurization aneroid switches are activated.
When aBLEEDAIR switch is set to OFF, the respective bleed-air shutoff/
pressure regulator valve will be energized to the closed position .
When a BLEED AIR switch is set to EMER, the respective bleed-air
shutoff/pressure regulator valve will supply low-pressure bleed air
and emergency pressurization valve will be de-energized open. The
bleed-airshutoff/pressure regulator valves control bleed air flow to the
cabin air distribution and temperature control system, wing anti-ice
system, and windshield anti-ice system. The bleed-air shutoff/pressure
regulator valves will close automatically whenever the respective ENG
FIRE PULL T-handle is pulled . Bleed-air for windshield alcohol tank
pressurization is still available with the shutoff/pressure regulator
valves closed . TheBLEEDAIRswitches remain effective during EMER
BUSmode.
BLEED AIR WARNING LIGHTS
RedBLEEDAIRL and BLEEDAIRR warning lights on the glareshield
annunciator panel, provide the crew with visual indication of a pylon
overheat condition or pylonbleed air ducting overheat condition. Each
light is operated by a thermal switch in the associated pylon bleed-air
ducting or a thermal switch in the associated pylon just aft of the forward
engine mount. The ducting thermal switches close if the duct
temperature should reach 645 (±10)°F (341 [S.5]°C) . The pylon thermal
switches will illuminate the respective light if the temperature in a pylon
exceeds 250 (±5)°F (121 [±2.7]°C) . The switches will open and the affected
BLEEDAIRLight will extinguish as the pylon cools.
6-22
PM-121
Change 3
Learjet 31A
Pilots Manual
CAB AIR SWITCH
The CABAIR switch, on the pressurization control panel, controls the
cabin-air flow control valve and the pressurization system cabin safety
valve. During ground operation, when the CAB AIR switch is in the
OFF position, the normally closed vacuum shutoff solenoid is energized
open through relays in the squat switch relay panel and regulated
vacuum from the pressurization vacuum regulator will open the cabin
safety valve. When the CABAIR switch is set ON, the vacuum shutoff
solenoid is de-energized, allowing the safety valve to drive closed under
increasing cabin pressure.
CAB AIR LIGHT (OPTIONAL)
An amber CAB AIRlight may be installed on the glareshield annunciator
panel which illuminates when the CAB AIR switch is in the OFF
position . This light serves to remind crew members to switch CABAIR
on prior to takeoff.
PRESSURIZATION AUTO-MAN SWITCH
TheAUTO-MAN switch, on the pressurization control panel, provides
automatic and manual mode selection for normal pressurization . When
the switch is set to MAN, solenoid valves in the regulated vacuum lines
are energized to remove regulated vacuum from the CABIN CONTROLLER
and apply regulated vacuum to the manual control valve.
The control valve is manually operated by the redUP-DNcontrol lever.
When the AUTO-MAN switch is set to AUTO, the solenoid valves deenergize
and allow regulated vacuum to the CABIN CONTROLLER
for automatic pressurization control. Normally, the AUTO-MAN
switch remains in theAUTO position .
CABIN CONTROLLER
With the CAB AIR switch ON and the pressurization AUTO-MAN
switch AUTO, the CABIN CONTROLLER, located on the pressurization
control panel, will automatically control cabin altitude. The controller
senses cabin altitude and rate-of-climb and automatically
modulates the primary outflow valve by regulating control servo vacuum
pressure. Prior to takeoff, the altitude selector knob, on the face of
the controller, should be set to selected cruising altitude or desired cabin
altitude. The RATE knob may be rotated to select and maintain a
comfortable pressurization rate for ascent or descent. For descent and
landing, the altitude selector should be set to landing field elevation.
PM-121
Change 3 6-23
Pilot's Manual
Learjet 31A
PRESSURIZATION MANUAL CONTROL LEVER (UP-DN)
With the CAB AIR switch ON and the pressurization AUTO-MAN
switch in MAN, cabin pressurization is controlled by the red UP-DN
manual control lever on the pressurization control panel. The lever
controls servo vacuum pressure to the primary outflow valve through
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
庞巴迪挑战者手册9(13)
