Hydraulics Flashcards
What are the names of the hydraulic systems?
System A
System B
Standby System
Each hydraulic system A/B has how many pumps that pressurize the system to ____ psi
2 pumps (engine/electric)
3000 PSI
Maximum hydraulic pressure is ____ psi
3,500 PSI
Hydraulic System A powers what components
Normal nose wheel steering
Landing Gear
Ailerons
Rudder
Elevator
Elevator feel
Flight spoilers (2 per wing)
Ground spoilers
Alternate brakes
No 1. thrust reverser
Autopilot A
Power transfer Unit (PTU)
Hydraulic System B powers what components
Alternate Nose wheel steering
Leading edge flaps/slats
Auto slats
Landing gear transfer unit
Ailerons
Rudder
Elevator
Elevator feel
Flight spoilers (2 per wing)
Trailing edge flaps
Normal brakes
No 2. thrust reverser
Autopilot B
Yaw Damper
The standby hydraulic system has how many pumps?
1 electric
How can the standby hydraulic pump be activated manually? (two ways)
What does this shut off?
Selecting either FLT CONTROL switch to STBY RUD. Or selecting the ALTERNATE FLAPS to ARM.
This shuts off hydraulic system pressure to the ailerons, elevators, and rudder by closing the flight control shutoff valve
Automatic operation of the standby hydraulic system activates when?
All of the following:
Loss of system A or B
Flaps extended
In flight, or wheel speed greater than 60 kts
FLT CONTROL switch A or B hydraulic system ON
The standby hydraulic system powers what
Rudder
Leading edge flaps/slats (extension only)
Thrust reverser
Yaw Damper
How is the crew alerted that the standby hydraulic system is activated?
Master Caution
FLT CONT (master caution)
STBY RUD ON light illuminates
The standby hydraulic fluid reservoir is connected to which hydraulic system to be refilled
Hydraulic System B
How is the crew indicated that a hydraulic system needs to be refilled (A/B)?
When can this message illuminate?
An RF is displayed on the hydraulic systems page next to the associated hydraulic system
This only can appear on the ground with both engines shut down, or after landing with the flaps retracted
How is the crew indicated that the Standby Hydraulic System quantity has dropped below 50%?
The LOW PRESSURE light illuminates on the STANDBY HYD panel
Which hydraulic pump in System A can get a leak and the system will continue to operate?
The engine driven pump
If the electric pump gets a leak the system will drain fluid until it is out
If Hydraulic System B gets a leak anywhere in its system will it be able to maintain pressure?
No
If there is a leak in the Standby Hydraulic system what happens?
The system will drain its fluid
The LOW QUANTITY light will illuminate
System B will lose fluid down to about 72% full
What happens if you turn of an engine driven hydraulic pump while the engine is running?
The engine driven pump continues to operate
The fluid is blocked
Why is the Hydraulic System A pump labeled ELEC 2?
Why is the Hydraulic System B pump labeled ELEC 1?
Because the power source for System A elec pump is the AC Transfer Bus 2
Because the power source for System B elec pump is the AC Transfer Bus 1
Where are the system A/B heat exchangers located?
System A is in main fuel tank 1
System B is in main fuel tank 2
What is the minimum fuel quantity to operate an electric hydraulic pump?
1,675 lbs in the respective tank
Minimum hydraulic pressure during preflight?
2,800 PSI
Turning the FLT CONTROL A or B switch to OFF does what?
Closes the flight control shutoff valve, isolating the ailerons, elevators, and rudder from the associated hydraulic system
Turning the FLT CONTROL A or B switch to STBY RUD does what?
Activates the standby hydraulic system pump and opens the standby rudder shutoff valve to pressurize the standby rudder control unit
Positioning the FLT CONTROL B switch to OFF or STBY RUD will also do what?
Disengage the yaw damper
The Landing Gear transfer unit will automatically provide hydraulic pressure to assist raising the landing gear when…
Aircraft is in flight
No 1. engine fails
Landing gear lever is UP
Either main gear NOT up and locked
If hydraulic system B fails the PTU powers what components in system B
Leading edge flaps
Slats
Autoslat operation
The PTU operates automatically under what conditions
System B engine driven pump pressure drops below a limit
Aircraft is in flight
Flaps are less than 15 deg. but not up
