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(2) S 724-017Do the following functional tests: (a) Autobrake Control Test (AMM 32-42-00/501). (b) Autobrake Application Test (AMM 32-42-00/501).
(3) S 844-018Put the airplane back to its usual condition.
(4) S 864-019Remove electrical power if it is not necessary (AMM 24-22-00/201).
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757 MAINTENANCE MANUAL
PARKING BRAKE SYSTEM - DESCRIPTION AND OPERATION
________________________________________________
1. General_______
A. The parking brake is used in conjunction with the hydraulic brake system (AMM 32-41-00/001) to apply the main landing gear wheel brakes when the airplane is on the ground and in a stationary mode.
B. The parking brake utilizes either right hydraulic system pressure (if system is pressurized), left hydraulic system pressure (if left system is pressurized and right is not), or pressure from an accumulator. Accumulator pressure is channeled through the normal brake system components to set the brakes for parking. A mechanism connected to the captain's brake pedals sets the parking brake.
C. Indication is provided in the flight compartment and on the nose landing gear. A PARKING BRAKE message is displayed on the EICAS (Engine Indicating and Crew Alerting System) on P2 panel, and a PARK BRAKE light on the control stand, above the parking brake handle, comes on.
D. AIRPLANES WITH PARKING LIGHT ON NOSE LANDING GEAR; There is also a parking brake ON light on P62 panel on the nose landing gear shock strut that comes on.
E. The parking brake keeps brakes set for up to 12 hours when normal brake system pressure is removed or indefinitely when the normal brake system pressure is available.
F. The parking brake accumulator serves as a backup pressure source for the normal brake system pressure providing a pressure source for one brake application when normal (right hydraulic system) or alternate (left hydraulic system) pressure is not available.
G. The parking brake is set by depressing the captain's brake pedals and latching them in this position by pulling the parking brake handle. This keeps the brake pedals depressed, and closes the parking brake valve to block leakage of brake pressure to return.
H. The parking brake system comprises the following components:
(1)
Parking brake lever/cable
(2)
Parking brake linkage mechanism
(3)
Parking brake valve
(4)
Accumulator
(5)
Accumulator isolation valve
(6)
Parking brake close sense relay
(7)
Parking brake switch
(8)
Indicators
(9)
Accumulator charging valve and gage
2. Component Details (Fig. 1)
_________________
A. Parking Brake Lever/Cable
_________________________
(1) The parking brake actuator lever is located in the flight compartment on the left side of the P10 control stand. The lever is connected by a cable to the linkage mechanism.
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MAINTENANCE MANUAL
PARKING BRAKE CABLE
SPRING
SEE H
LEVER
PAWL
SHAFT CONTROL STAND SEE A
BRAKE PEDAL LINKAGE MECHANISM
SEE B
BRAKE PEDALS
INDICATOR LIGHT SEE C PARK BRAKE
P A R K
B R A K E
PARKING
BRAKE
HANDLE
CONTROL STAND
A C
PARKING BRAKE INDICATOR LIGHT
LIGHT-PARKING
BRAKE ON
1
NOSE LANDING GEAR GROUND BRAKE PRESS
CREW INDICATION 4
PSI X 1000
(P62 PANEL) 30
FLIGHT 2 1 COMPARTMENT FLOOR
BRAKE ACCUMULATOR PRESSURE INDICATION (P3 PANEL)
PARKING BRAKE PARKING
SPRING SWITCH BRAKE CABLE
CONTROL ARM
PAWL
SWITCH
ACTUATING CAM
LINKAGE MECHANISM
1
GUN 051 B H
Parking Brake System - Component Location Figure 1 (Sheet 1)
E10695
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MAINTENANCE MANUAL
SEE F
SEE G
SEE E PRESSURE SEE D
GAGE CHARGING
VALVE
CHARGING VALVE/GAGE E
MOTOR
VALVE
ACCUMULATOR
PARKING BRAKE VALVE F
VALVE
PRESSURE TRANSMITTER
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本文链接地址：757 AMM 飞机维护手册 起落架 CHAPTER 32 - LANDING GEAR 3(53)
