Hydraulic

Question 1

Which hydraulic accumulator is responsible for supplying hydraulic pressure for emergency brake applications?

Answer 1

System #2 accumulator.

Reference: OM Vol. 2, Section 2-11, Hydraulic System

Question 2

The System 2 accumulator has enough stored hydraulic pressure to supply a total of ________ applications or ________ hours of continuous emergency brake pressure?

Answer 2

6 applications or 24 hours.

Reference: OM Vol. 2, Section 2-11, Hydraulic System

Question 3

During normal flight, the engine driven hydraulic pump supplies a total pressure
output of _______ PSI.

Answer 3

3,000 PSI.

Reference: OM Vol. 2, Section 2-11, Hydraulic System

Question 4

Which hydraulic system is responsible for flap operation?

Answer 4

Neither, the flap motors are DC powered and do not depend on hydraulic power for operation.
Reference: OM Vol.2, Section 2-11, Hydraulic System

Question 5

Assuming both engines running with the electric hydraulic pump knob in the
AUTO position, what is the status of the electric hydraulic pumps?

Answer 5

The pump is kept in standby until the engine driven pump pressure drops below a set value of 1600 PSI or the associated engine N2 drops below a set value of 56.4%N2.
Reference: OM Vol.2, Section 2-11, Hydraulic System

Question 6

Can the hydraulic system temperature be monitored on the EICAS or MFD’s?

Answer 6

No.

Reference: OM Vol.2, Section 2-11, Hydraulic System

Question 7

The ailerons are normally powered by which hydraulic system(s)?

Answer 7

System 1 and System 2.

Reference: OM Vol.2, Section 2-11, Hydraulic System

Question 8

Can the hydraulic quantity for system 1 and system 2 be monitored?

Answer 8

Yes, MFD (HYD) Hydraulics page.

Reference: OM Vol.2, Section 2-11, Hydraulic System

Question 9

If describing the hydraulic systems what is the main difference between system 1 and system 2 from a mechanical/components standpoint?

Answer 9

System 1 utilizes a priority valve.

Reference: OM Vol.2, Section 2-11, Hydraulic System

Question 10

What is the purpose of the priority valve in hydraulic system 1?

Answer 10

It restricts hydraulic pressure from the landing gear during retraction to ensure adequate hydraulic pressure for the flight controls during electric hydraulic pump operation. The system 1 accumulator pressure will provide the necessary pressure required for gear retraction during this particular instance.
Reference: Vol.2, Section 2-11, Hydraulic System

Question 11

In essential power, are the electric hydraulic pumps powered?

Answer 11

No, they are DC powered.

Reference: OM Vol.2, Section 2-11, Hydraulic System

Question 12

The hydraulic accumulator #1 provides pressure for what?

Answer 12

Landing gear retraction.

Reference: OM Vol.2, Section 2-11, Hydraulic System

Question 13

The hydraulic accumulator #2 provides pressure for what?

Answer 13

Emergency Brakes.

Reference: OM Vol.2, Section 2-11, Hydraulic System

Question 14

In normal cruise flight conditions, the electric hydraulic pumps are producing a psi output of___________.

Answer 14

0 PSi.

Reference: OM Vol.2, Section 2-11, Hydraulic System

Question 15

. The nose wheel steering is hydraulically powered by which hydraulic system?

Answer 15

Hydraulic System 1.

Reference: OM Vol.2, Section 2-11, Hydraulic System

Question 16

During a hydraulic system test, what is the first step in performing the test?

Answer 16

Ensure that the nose wheel steering is disengaged and both engine hydraulic pump shutoff buttons are deselected (normal position).
Reference: OM Vol.1, Section 3, Normal Procedures Receiving Flow