Hydraulics Flashcards
The hydraulic systems on the 737 are designated as ____.
System A, System B, and Standby
Normal hydraulic system pressure is ____ psi.
3000
Which of the following components are normally powered by Hydraulic System A?
Nosewheel steering (normal)
Which of the following components are normally powered by System B?
Trailing Edge Flaps
If either System A or System B is lost, the remaining system can power ____ with no decrease in airplane controllability.
the primary flight controls
Turning Engine 1 or Engine 2 Hydraulic Pump Switches OFF ____.
blocks pump pressure output to the components
Moving a FLT CONTROL switch to the STBY RUD position ____.
- activates the Standby Pump
- extinguishes the Flight Control LOW PRESSURE light when the Standby Rudder Shutoff Valve opens
How are System A & B reservoirs pressurized?
Bleed air
Main Hydraulic System A or B pressure is generated by ____.
both an AC electric motor-driven pump and an engine-driven pump
An engine-driven hydraulic pump supplies approximately _____ times the fluid of an electric motor-driven pump.
6
To block hydraulic fluid flow to the engine driven pump, ____.
pull the respective engine Fire Handle
Heat exchangers used for cooling hydraulic fluid are located ____.
in Main Fuel Tank #1 for System A
in Main Fuel Tank #2 for System B
With System A fluid level at the top of the standpipe, the reservoir quantity displayed indicates approximately ____ % full.
20
With fluid level at the top of the standpipe, fluid remaining in the System B reservoir is sufficient for operation of the ____.
Power Transfer Unit
The purpose of the Power Transfer Unit (PTU) is to ____.
supply hydraulic fluid volume needed to operate autoslats and leading edge flaps and slats
The Power Transfer Unit (PTU) in A/C 3AA-3LB operates automatically when ____.
- System B engine-driven pump pressure drops below limits
- airborne
- flaps are less than 15 degrees but not up
The Landing Gear Transfer Unit operates when ____.
- airborne and No. 1 engine RPM drops below a limit value
- the landing gear lever is positioned UP and a main gear is not up and locked
The automatic operation of the Standby Hydraulic System is initiated when all the following conditions exist:
Loss of system A or B pressure, flaps extended, airborne, or wheel speed greater than 60 knots.
The Standby Hydraulic System LOW QUANTITY Light illuminates when the reservoir is ____.
approximately 1/2 empty
If a leak develops in Hydraulic System A engine-driven pump or its related lines, a ____ in the reservoir prevents a total system fluid loss.
standpipe
If a leak develops in Hydraulic System A electric motor-driven pump or its related lines, the hydraulic fluid quantity in the reservoir decreases to ____.
0
The Power Transfer Unit (PTU) uses ____ pressure to power a hydraulic motor-driven pump which pressurizes ____ fluid for use in operating leading edge flaps and slats.
System A, System B
The minimum hydraulic System A and B pressure is ____ psi for preflight.
2800
