AME Aircraft Propeller Systems and Theory

Question 1

What is the primary purpose of a constant-speed propeller governor?

Accepted Answer

To maintain a constant engine RPM by varying blade pitch

Answer

To maintain a constant blade angle regardless of airspeed

Answer

To prevent propeller overspeed by reducing throttle

Answer

To synchronize propeller rotation with engine firing order

Question 2

On a hydraulically actuated variable-pitch propeller, what fluid is typically used as the actuating medium?

Accepted Answer

Engine oil

Answer

Skydrol hydraulic fluid

Answer

MIL-H-5606 hydraulic fluid

Answer

Water-glycol mixture

Question 3

What is 'propeller feathering'?

Accepted Answer

Rotating blades to approximately 90° pitch to minimize drag on a failed engine

Answer

Rotating blades to minimum pitch for maximum thrust

Answer

Balancing the propeller by adding weights to blade tips

Answer

Applying a protective coating to the leading edges of the blades

Question 4

Propeller 'tracking' is a maintenance check that verifies:

Accepted Answer

Each blade tip follows the same plane of rotation

Answer

The propeller RPM is within limits

Answer

The propeller governor is correctly calibrated

Answer

Blade angle settings are within specified tolerance

Question 5

What typically happens to a constant-speed propeller if the governor oil pressure is lost?

Accepted Answer

The blades move to high pitch (coarse) or feather

Answer

The blades move to low pitch (fine)

Answer

The blades freeze in their current position

Answer

The propeller immediately overspeeds

Question 6

A propeller static balance check ensures:

Accepted Answer

The center of gravity of the propeller assembly is on the axis of rotation

Answer

The propeller generates equal thrust from all blades

Answer

Each blade has the same pitch angle

Answer

The propeller can withstand centrifugal force loads