Hydraulics

Question 1

What is the maximum temperature of the G550’s hydraulic fluid?

Answer 1

104 degrees C.

Question 2

What does the Amber “X” indicate in the left hydraulic system?

Answer 2

Quantity of hydraulic fluid is unknown, most likely due to a leak in the left hydraulic system. Once the main reservoir of the left system is empty, the quantity of hydraulic fluid in the “AUX” reservoir is unknown.

Question 3

What is the bootstrap of a hydraulic pump?

Answer 3

Maintains steady pressure (back pressure) on the pump that helps prevent cavitation.

Question 4

What is the minimum pressure that is required in the brake accumulator in order to set the parking brake?

Answer 4

1700psi.

Question 5

If the brake accumulator is indicating 1200psi (pre-charge level), what amount of braking is available for braking?

Answer 5

O psi.

Question 6

In the hydraulic system, what is a DPI?

Answer 6

Differential Pressure Indicator, located on the hydraulic system filter manifolds.  There are a total of 10.
Left - 5
Right - 3
PTU -1
AUX - 1

Question 7

What is the BWI in the PTU in the right hydraulic system?

Answer 7

A Bearing Wear Indicator. Indication of shaft wear in the PTU (motor on the right side and pump on the left side).

Question 8

What will cause the AUX PUMP to “latch”?

Answer 8

Brakes depressed > or = 10 degrees
And L SYS < 1500 psi
Or PTU SYS < 1500 psi

Question 9

What is the PTU “Activation” criteria?

Answer 9

The PTU is armed
L HYD is < 1500 psi
L HYD is > or = 1.5 gallons
R HYD temp < 104 degrees

Question 10

When would a crew need a standby rudder?

Answer 10

Only required for dual hydraulic failure.

Question 11

What are the only two systems tied to the nose wheel WOW switch?

Answer 11

NWS and STDY RUDDER.