-release the door from its uplock.
1EFF : ALL 1 32-31-00Page 89 1 1 May 01/05R 1 1 1CES 1
MLG Door Ground Opening Figure 045
1EFF : 1 1R 1CES ALL 1 11 1 32-31-00 Page 90 May 01/05
NLG Door Ground Opening Figure 046
1EFF : 1 1R 1CES ALL 1 11 1 32-31-00 Page 91 May 01/05
NLG/MLG Door Ground Opening By-Pass Valves (2517GM,2518GM,2533GM) Figure 047
1EFF : ALL 1 32-31-00Page 92 1 1 May 01/05R 1 1 1CES 1
(1) Operation
The operation of the door by-pass valve isolates the door actuating
cylinder from the hydraulic supply.
The door, when released from its uplock, opens because of gravity or
may be manually assisted.
Each by-pass valve (2517GM/2518GM/2533GM) has three hydraulic
connections marked A, B and C:
-
Port A : door open line
-
Port B : door close line from the selector valve
-
Port C : door close line to the door actuator.
For normal operation, Port A is closed with Port B connected to Port
C.
For door ground opening, Port B is closed before Port A is connected to Port C.
A locking plunger (baulk) in the by-pass valve stops the movement of the control lever from the OPEN to the CLOSE position. Before selection can be made, a hydraulic pressure greater than 70 bars (1015 psi) must be supplied to port B (doors close line) to retract the locking plunger.
A more detailed description and operation of the L/G door ground-opening is given in (Ref. 32-12-00).
T. Landing Gear Control and Interface Unit (LGCIU), (5GA1,5GA2)
(Ref. Fig. 011, 048, 049, 050, 051, 052, 053)
(1) General
There are two identical Landing Gear Control and Interface Units (LGCIU):
-
SYSTEM NO 1 LGCIU (5GA1), which is located in rack 90VU (Shelf 93VU)
-
SYSTEM NO 2 LGCIU (5GA2), which is located in rack 90VU (Shelf 94VU).
The function of each LGCIU is to:
-control the operation of the landing gear (L/G) and doors
-find the position and status of the L/G and doors
-supply L/G and door position and status information to other aircraft systems
1EFF : ALL 1 32-31-00Page 93 1 1 May 01/05R 1 1 1CES 1
-process proximity sensor inputs from the Flap disconnect system (Ref. 27-51-00)
-supply data to the Slat and Flap Control Computer (SFCC) (Ref. 27-51-00)
-process proximity sensor and microswitch inputs from the Cargo Door Control System (Ref. 52-35-00)
-provide a control logic circuit for the Cargo-Compartment Door-Systems (Ref. 52-35-00)
-monitor LGCIU system operation and report component/system failures to the Flight Warning Computer (FWC) (Ref. 31-53-00) and Electronic Centralized Aircraft Monitoring System (ECAM) (Ref. 31-60-00)
-store details of failures and to supply this information to the Centralized Fault Display System (CFDS) (Ref. 31-30-00)
-provide BITE and self monitoring functions
-simulate any landing gear configuration for maintenance test and failure investigation tasks.
The two LGCIU's are interchangeable, but the aircraft wiring in SYSTEM NO 1 is different to that of SYSTEM NO 2. Thus the installed LGCIU's will supply different interfaced aircraft systems with L/G system position information (Ref. 32-62-00).
The aircraft can operate satisfactorily when one of the LGCIUs does not operate or is not installed. When this occurs the serviceable unit must be installed in SYSTEM NO.1 (Shelf 93VU).
Only one LGCIU is in control of the L/G system at any one time. Control of the L/G system automatically changes to the other LGCIU on:
-each de-selection of DOWN of the L/G control-lever
-detection of a failure in the LGCIU/L/G system of the LGCIU which has control of the L/G.
To permit the automatic change of one LGCIU to the other, each LGCIU supplies a status signal to the other.
Each LGCIU is connected to the other LGCIU by two pairs of wires that supply LGCIU status signals. For each LGCIU, one pair of wires is for the output status signals to the other LGCIU. The second pair of wires is for input status signals from the other LGCIU.
Each LGCIU will continue to supply L/G position and status information to the interfaced aircraft systems. It does not matter which LGCIU has control of the L/G system.
Each LGCIU consists of an ARINC 600 4 MCU case, that has:
-7 Printed Circuits Boards (PCB)
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：A320飞机维护手册 AMM LANDING GEAR 起落架4(47)
