Hydraulic Power System Flashcards
Overview 1
A hydraulic reservoir supplies fluid to two engine driven pumps, each mounted on the respective engine accessory drive pad.
An additional electrical auxiliary pump is mounted inside the aircraft fuselage.
Overview 2
When one or both engines running, the engine driven hydraulic pumps supply 3 000 psi pressure to power the hydraulic subsystems.
These include the landing gear, breaks, speed brakes/spoilers, thrust reversers, and nose wheel steering.
How many engine driven hydraulic pumps are on the Soverign?
Primary fluid flow is provided by two engine driven pumps.
Where are the engine driven hydraulic pumps found?
One on each engine accessory drive pad.
The auxiliary hydraulic pump is powered by?
The auxiliary hydraulic pump is powered by the main DC electrical system.
What is the primary function of the auxiliary hydraulic pump?
The auxiliary pump is for ground use only and is used primarily to set the parking brake when the engines are not running.
Hydraulic switches L-R ENG: ON
The L and R ENG buttons on the hydraulic pump sub panel control the position of their respective hydraulic unloading valves.
In the ON position, the solenoid is deenergised closed, allowing the engine driven pump tp pressurize the system.
Hydraulic switches L-R ENG: UNLOAD
The UNLOAD position opens the respective engine hydraulic pump unload valve and relieves pump pressure via the return lines to the reservoir.
Hydraulic switches, AUX :
The AUX button on the hydraulic pump sub panel is a two position button that requires main DC electrical power to operate the pump.
EICAS DISPLAY
The hydraulic area is displayed on the lower right side of the EICAS display. Digits represent total hydraulic system pressure and not an individual pump pressure.
If the hydraulic pressure is within the normal operating range, what color are the digits?
Green.
If the hydraulic pressure is outside the normal operating range, what color are the digits?
The PRESSURE digits turn inverse video amber.
When the hydraulic pressure is too high, how are you alerted?
The HYDRAULIC PRESSURE TOO HIGH, Amber CAS message is displayed.
When the pressure delivered by either pump is too low, how are you alerted?
The HYDRAULIC PRESSURE LOW L-R CAS message is displayed on the EICAS.
When is the HYDRAULIC VOLUME LOW, CAS message displayed?
This message is displayed when the hydraulic reservoir volume is less than 120 cubic inches.
