Boeing B777 - Hydraulics
Both left and right hydraulic systems have a shut-off valve that isolates the engine driven-pump from the reservoir. Which control will close the shut-off valve?
What will cause any primary or demand pump FAULT light to illuminate?
The engine fire switches must be _____ to close the engine–driven pump hydraulic supply shutoff valve and to depressurize the engine–driven pump.
In the AUTO position which hydraulic demand pump(s) operate(s) continuously when the airplane is on the ground?
The RAT provides hydraulic and electrical power:
The PRIMARY C1 pump draws hydraulic fluid via a standpipe in the reservoir, while all other center system pumps draw fluid from the bottom of the center system reservoir.
The PRIMARY C1 pump draws hydraulic fluid from the bottom of the center system reservoir, while all other center system pumps draw fluid via a standpipe in the reservoir.
If both air–driven pumps are selected to ON, they can operate simultaneously in very specific conditions.
If both air–driven pumps are selected to ON, only air–driven pump C1 operate: the two air–driven pumps cannot operate simultaneously when both are selected ON.
The leading edge slats are reconnected to the center hydraulic system and allowed to operate in primary mode when center hydraulic fluid quantity recovers to normal for 5 seconds, and:
In what order are the hydraulic pumps switched on prior to engine start?
Two electric motor-driven pumps are the Primary hydraulic power sources for the center hydraulic system.
Advertisement
An hydraulic pump that has overheated, is displayed on the Hydraulic synoptic with an amber cross.
A pump that has failed, displays with an amber cross. An OVHT display appears next to a pump symbol when the pump is overheated.
A hand pump and reservoir quantity gauge allows for servicing all system reservoirs from one location. Left and right system reservoirs center system reservoir, are located in the main gear wheel well area.
A hand pump and reservoir quantity gauge allows for servicing all system reservoirs from one location. Left and right system reservoirs are located in the respective engine strut and center system reservoir is located in main gear wheel well area.
When will a center hydraulic pump "FAULT" light be illuminated?
What type of hydraulic pumps are used in the Left hydraulic system?
How are hydraulic reservoirs pressurized?
Pilots pressurize the right hydraulic system before the other systems to prevent fluid transfer between systems.
The RAT can be deployed manually by pushing the RAM AIR TURBINE switch. The RAT is deployed by a compressed spring. The hot battery or APU battery bus must be powered. The center hydraulic system needs to be powered too. Once deployed, the RAT cannot be stowed in flight.
The hot battery or APU battery bus must be powered, but the center hydraulic system does not need to be powered.
On the STATUS page, what does the hydraulic pressure display?
The RAT provides can supply hydraulic and electrical power simultaneously.
When deployed, the RAT provides hydraulic power only to the primary flight control components of the center hydraulic system.
In AUTO, when will the center demand pumps operate?
Advertisement
With the C1 Demand pump switch at ON, when will the pump run?
A what pressure will the RAT green PRESS light illuminate?
The Primary Pump is driven by the associated engines accessory drive. With a loss of electrical power, this type of pump is designed to turn to the ON condition. Therefore, electrical power is required to turn off a Primary Pump.
The Center System can be pressurized by:
Where is the hydraulic system quantity displayed?
In what order are the hydraulic pumps switched off after engine shutdown?
What is the purpose of the Center Hydraulic System Demand pumps?
What should be the position of the Left and Right Primary pump switches after the Shutdown Procedure is complete?
How are the Center hydraulic system Primary pumps driven?
If center hydraulic system quantity is sensed to be low and _______ , alternate brakes are isolated from the center system and remain operable using reserve fluid, nose gear actuation and steering are isolated and leading edge slats are isolated and not allowed to operate in the primary hydraulic mode.
Advertisement
The engine driven pump on each system is considered the "primary pump", while the electric motor-driven pump is designated as the "demand" pump.
Primary pumps are designed for continuous operation, while demand pumps normally operate only when demand is high or the primary pump has failed.
How is the hydraulic normal fluid level indicated?
An hydraulic pump that is on, displays in green with a green flow line. A pump that is off, displays as an open amber box.
A pump that is on, displays in green with a green flow line. A pump that is off, displays as an open white box.
What does the right hydraulic system power?
The Flight Control Hydraulic Power switches are installed for:
In flight when does the RAT deploy automatically?
If the RAT is unable to maintain _____, the RAT generator electrical load is shed until RPM is satisfactory.
When faced with a choice between hydraulic power to the flight controls or electrical power to the aircraft, the RAT will choose hydraulic power as its priority.
The below hydraulic status is displayed.
LO displays in amber when the reservoir quantity is low. LO can only display in flight.
The ______ powers most of the high load components.
It powers the flight controls, the leading edge slats, the trailing edge flaps, the landing gear actuation, the alternate and reserve brakes, The nose gear steering, and the main gear steering.