Hydraulic System Flashcards
How many hydraulic systems are installed in the CRJ-700?
Three independent hydraulic systems.
What is the function of the pressurized hydraulic fluid?
Pressurized fluid powers the primary and secondary flight controls, the wheel brakes, nose wheel steering, thrust reversers and the landing gear extension and retraction.
Where is the hydraulic system status monitored from the cockpit?
The primary, status and hydraulic system synoptic pages.
How many hydraulic systems power the primary flight controls?
Primary flight controls are powered by three hydraulic systems. This redundancy prevents the loss of critical flight controls due to failure of a single hydraulic system.
How many hydraulic pumps are installed in each hydraulic system?
Each hydraulic system has two hydraulic pumps, one for normal power and a second
as supplementary power.
What are the locations of the hydraulic system servicing panels?
Servicing of the hydraulic systems is accomplished on the ground at the service panels located in the aft equipment bay, below the left and right equipment racks (systems 1 & 2) and on the right side of the aircraft aft of the wing root (system 3).
What is the function of the engine driven hydraulic pump (EDP)?
The EDP’s are provided with hydraulic fluid direct from its respective reservoir through a firewall shutoff valve. Each EDP provides pressurized flow to a pressure manifold for distribution to its user systems.
What is the normal output pressure of the engine driven pump (EDP)?
The working pressure of the EDP is 3,000 psi +/- 200 psi.
What is the normal output pressure of the ac motor pump (ACMP)?
The working pressure of the ACMP is 3,000 psi +/- 200 psi.
What is the function of the “AUTO” position of the ACMP 1b and 2b switches located on the Hydraulic Control Panel?
Pumps 1b & 2b will activate automatically in the “AUTO” position when their respective buses are powered, and generator is operating and the flaps are not at zero to assist the EDP’s during high demand periods (takeoff, approach & landing).
What is the function of the Hydraulic System Shutoff Valves located on the Hydraulic Shutoff Valve Control Panel?
The purpose of the SOV is to stop the flow of hydraulic fluid and allow the fluid to cool in order to control an over temperature without having to shut down the engine, of in the event of a fluid leak in the system.
What is the function of the Left Hydraulic Shutoff Valve switchlight located on the Hydraulic Shutoff Control Panel?
It closes the left hydraulic shutoff valve located between the EDP and the reservoir in system number one.
What is the function of the Right Hydraulic Shutoff Valve switchlight located on the Hydraulic Shutoff Valve Control Panel?
It closes the right Hydraulic Shutoff Valve located between the EDP and the reservoir in system number two.
What is the location of hydraulic systems 1 & 2 shutoff valves (SOV’s)?
The Hydraulic Shutoff Valves are located in the supply lines between the reservoir and the engine driven pumps.
How is fluid cooling accomplished for hydraulic systems one and two?
The hydraulic fluid is cooled by an air heat exchanger located in the left side of the aft equipment bay. Cooling air from the ram air scoop at the base of the vertical stabilizer is sent through the heat exchanger and exhausted out the left rear fuselage aft of the number one engine pylon.
