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

A constant-speed governor maintains engine RPM by automatically adjusting propeller blade pitch to match varying flight conditions.

Question 2

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

Accepted Answer

Engine oil

Answer

Most variable-pitch propeller systems use engine oil as the actuating fluid because it is readily available and provides the required pressure.

Question 3

What is 'propeller feathering'?

Accepted Answer

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

Answer

Feathering turns propeller blades edge-on to the airflow (approximately 90°) to reduce drag when an engine fails in flight.

Question 4

Propeller 'tracking' is a maintenance check that verifies:

Accepted Answer

Each blade tip follows the same plane of rotation

Answer

Tracking ensures all propeller blade tips rotate in the same plane, indicating the hub is not bent and blades are properly installed.

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

Most constant-speed propellers are designed so that loss of oil pressure causes blades to move toward high pitch or feather as a fail-safe against overspeeding.

AME - Aircraft Maintenance Engineer Practice Test

AME - Aircraft Maintenance Engineer Practice Test

AME Aircraft Propeller Systems and Theory