AMT AMT Hydraulics, Pneumatics & Landing Gear

Question 1

What principle states that pressure applied to an enclosed fluid is transmitted equally in all directions?

Accepted Answer

Pascal's law

Answer

Pascal's law states that pressure applied to a confined fluid is transmitted undiminished in all directions throughout the fluid.

Question 2

Which type of hydraulic fluid is most commonly used in modern commercial transport aircraft in the US?

Accepted Answer

Skydrol (phosphate ester-based)

Answer

Skydrol, a phosphate ester-based fluid, is the most widely used hydraulic fluid in modern commercial transport aircraft because of its fire-resistant properties.

Question 3

What is the primary function of an aircraft hydraulic accumulator?

Accepted Answer

To store pressurized fluid and dampen pressure surges

Answer

A hydraulic accumulator stores pressurized fluid under a pre-charged gas pressure to dampen system pressure surges and provide an emergency fluid reserve.

Question 4

What safety precaution must be taken before opening any hydraulic line on an aircraft?

Accepted Answer

Depressurize the hydraulic system completely

Answer

The hydraulic system must be fully depressurized before opening any line to prevent high-pressure fluid injection injuries and uncontrolled actuator movement.

Question 5

What does a hydraulic system relief valve do?

Accepted Answer

Limits maximum system pressure by bypassing fluid back to the reservoir

Answer

A relief valve protects the hydraulic system by opening to route fluid back to the reservoir when system pressure exceeds the maximum allowable limit.

AMT - Certified Aircraft Maintenance Technician Practice Test

AMT - Certified Aircraft Maintenance Technician Practice Test

AMT AMT Hydraulics, Pneumatics & Landing Gear