Airframe Mechanic Certification Hydraulic and Pneumatic Power 4

Question 1

What type of actuator converts hydraulic pressure into linear mechanical motion?

Accepted Answer

Linear actuator (hydraulic cylinder)

Answer

A linear actuator (hydraulic cylinder) uses fluid pressure acting on a piston to produce straight-line mechanical force and movement.

Question 2

Which component prevents reverse flow in a hydraulic or pneumatic line?

Accepted Answer

Check valve

Answer

A check valve allows flow in only one direction and blocks reverse flow, protecting upstream components from back-pressure.

Question 3

The purpose of a hydraulic snubber on a pressure gauge is to:

Accepted Answer

Dampen pressure surges to protect the gauge and provide steady readings

Answer

A snubber is a restrictor that dampens rapid pressure fluctuations, protecting the gauge mechanism from damage and providing a stable, readable indication.

Question 4

When MIL-PRF-5606 (red) and MIL-PRF-83282 (red) hydraulic fluids are inadvertently mixed, the result is:

Accepted Answer

Generally acceptable because both are petroleum-based and compatible

Answer

MIL-PRF-5606 and MIL-PRF-83282 are both petroleum-based mineral oils and are considered compatible with each other and the same seal materials.

Question 5

A double-acting hydraulic actuator differs from a single-acting actuator in that it:

Accepted Answer

Can apply hydraulic pressure to extend AND retract the piston

Answer

A double-acting actuator has ports on both sides of the piston, allowing hydraulic pressure to power both extension and retraction strokes.

Airframe Mechanic Certification Practice Test

Airframe Mechanic Certification Practice Test

Airframe Mechanic Certification Hydraulic and Pneumatic Power 4