Hydraulics Flashcards
How many hydraulic systems does the aircraft have?
Three. Main systems A & B, and the Standby system
Where are the hydraulic fluid reservoirs located?
In the main wheel well
Which systems use hydraulic fluid?
Flight Controls, Leading edge devices, Trailing edge flaps, Landing gear, Wheel brakes, Nose wheel steering, Thrust reversers, Autopilot
Normal hydraulic system operating pressure
3,000 psi
Maximum hydraulic system operating pressure
3,500 psi
How many pumps do the Hydraulic A & B systems have?
2 each - An engine driven pump and an electric motor driven pump
How many pumps does the standby hydraulic system have?
1 electric motor driven pump
T/F: Hydraulic A’s engine-driven pump is powered by the No. 2 engine
False (No. 1 Engine)
Yaw dampener uses fluid from ____________ for it’s operation
Hydraulic System B
Two ways of manually activating the Standby Hydraulic Pump
- Selecting either FLT CONTROL switch to STBY RUD
- Selecting the ALTERNATE FLAPS Master switch to ARM
When does the STANDBY HYD LOW QUANTITY light illuminate?
When the standby fluid level drops below 50%
The standby hydraulic reservoir is serviced/filled through Hydraulic System ______Reservoir
B
An RF next to the hydraulic quantity on the Lower Display unit indicates….
That reservoir needs to be serviced/refilled. (Only displays on the ground with engines shut down or after landing with flaps retracted)
T/F: The standby reservoir is not directly pressurized by bleed air
True. (However, Hydraulic B is pressurized and exerts some of that pressure on the standby)
The power source for hydraulic system A & B respective electric pumps is
A - AC Transfer Bus 2
B - AC Transfer Bus 1
For the hydraulic fluid heat exchangers to provide proper cooling there must be ____________ pounds of fuel in the related main tank
1,675
The preflight minimum hydraulic pressure for the main systems (A&B) is
2,800 psi
After a No. 1 engine failure, the Landing Gear Transfer Unit will help raise the gear using hydraulic fluid from __________
Hydraulic System B
T/F: The electric motor driven hydraulic pumps are able to pump the same volume as the engine driven pumps
False. It can match the pressure (3,000 psi) but the volume is lower
The PTU uses fluid pressure from system ____ to drive a pump which in turn pressurizes system ___when its engine driven pump pressure is lost.
A, B
The Hydraulic Power Transfer Unit (PTU) operates what?
Leading edge flaps, Slats, Autoslat
What happens when an ENG 1 or ENG 2 hydraulic switch is set to OFF?
Its corresponding blocking valve is energized which blocks the fluid downstream of the pump (the pump continues to operate)
The associated LOW PRESSURE light illuminates
What does an OVERHEAT light on the Hydraulic Panel indicate?
Hydraulic fluid used to cool & lubricate the electric pump has overheated, or the pump itself has overheated
System hydraulic fluid passes through a ___________ before returning to the reservoir
heat exchanger located in the same side main fuel tank
