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
after slat retraction when in-flight. Fuel transfer will begin from the ACT 2 when
the center tank is no longer full. Transfer will continue until either the center tank
is full or both ACT’s are empty. After ACT transfer starts if the center tank
becomes full transfer will stop until the center tank burns down sufficiently and
the transfer process will automatically restart.
ACT 1
(forward)
ACT 2
(aft)
An amber FAULT light will illuminate in the ACT pb if the center tank has less
than 6,614 lbs. of fuel and one ACT has more than 550 lbs. of fuel which would
indicate that the AUTO schedule was not being followed. If the ACT pb is
selected to FWD then all ACT fuel will be manually transferred forward to the
center tank using the ACT transfer pump, which is a backup pump that can
pump from either ACT. This backup ACT XFR pump runs at a low volume and
may not be able to transfer all fuel at higher altitudes (FL270 and above) or
supply as fast as the engines are burning. Chapter 21 will specify best
procedures for complete transfer of fuel in case of ACT transfer FAULT.
It is normal to have fuel being transferred from the ACT’s to the Center tank and
from the Center tank to the Wing tanks at the same time. On the A321 there’s a
whole lotta transferring goin’ on. Please note that in order to feed an engine from
the opposite wing you must still open the fuel crossfeed valve. In normal AUTO
operation the fuel procedures are the same and fuel transfer operation is
transparent to the pilot.
Note: For the A321 all fuel is burned from the Wing tanks. Fuel must be
transferred to a Wing tank for it to be available for use by the engines. There is
no ECAM CTR TANK FEEDG memo as the A321 never feeds from the Center
Tank.
Note: For A321: if center tank is not full then do not takeoff with fuel in an ACT
(PH 2.8.3)
Note: on the SD FUEL display the left ACT is #1 (forward) and the right ACT is
#2 (aft). Gee, why not just display them as fore and aft?
US Airways Airbus A319, A320, A321 Notes
18
Pneumatics, Air Conditioning & Pressurization (TM 7-36.x, TM 7-21.x)
The pneumatic system supplies high pressure air for:
Air conditioning
Pressurization
Engine starting
Wing anti-icing
Hydraulic reservoir pressurization
Aft cargo heat
Water tank pressurization
High pressure air can be supplied by:
Engine bleed
APU load compressor
High pressure ground connection
Controlled by BMC (Bleed Monitoring Computer)
Engine Bleeds close automatically when BMC's detect:
A APU bleed valve open
S Engine Start
O Over temperature
L Leak
O Over pressure
The valve will also automatically close pneumatically when:
Low pressure
Reverse flow
And is electrically closed when:
ENG BLEED selected off
ENG FIRE pb selected
The APU bleed will close for leaks
The APU is ready for bleed when reaching 95% for two seconds or 99.5%. The
AVAIL light will show in the APU start pb and green APU AVAIL will show on
EWD display when APU is available for use.
The crossbleed valve can be operated in automatic or manual mode. There are
two electric motors for the valve, one for each mode. In automatic mode the
US Airways Airbus A319, A320, A321 Notes
19
crossbleed valve opens automatically when using APU bleed air. During normal
operation the crossbleed is closed to isolate the two engine bleeds.
The crossbleed is manually set OPEN during the engine crossbleed start
procedure.
The leak detection system uses a single loop for the pylons and APU to detect
hot air temps associated with duct leaks. Dual loops are used for the wings. If
both of the dual loops detect a leak a warning is given, unless there is a fault on
one, then only one loop is required to give a warning.
If a leak is detected:
The engine bleed air valve (APU bleed air valve) on that side is closed
Associated ENG (APU) BLEED FAULT light comes on
Crossbleed valve closes (except during engine start)
Left wing leak only – APU bleed air valve closes (except during ENG start)
Packs
Airbus Gotcha: Do not use external conditioned air when using packs (PH
1.7.2). Unfortunately, there is no cockpit indication of external air connected! You
can turn off the cabin fans pb and if air continues to blow from the vents then
external air is connected.
Pay attention here, many new Airbus pilots fail to understand the way the Zone
Temp system works. If you are familiar with the 737-400 this is very similar. Both
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
航空资料4(156)
