Part-66 Module 17 practice test

Question 1

What happens to a fixed-pitch propeller blade's angle of attack as forward speed increases at constant rpm?

Accepted Answer

It decreases

Answer

It increases

Answer

It stays constant

Question 2

Why is a propeller blade twisted, with a smaller blade angle at the tip than at the root?

Accepted Answer

The tip moves faster, so it needs less angle

Answer

To make the thin tip stronger against bending

Answer

To reduce weight and inertia at the root

Question 3

What is the advance ratio of a propeller?

Accepted Answer

Forward speed over tip speed (or rpm × diameter)

Answer

The number of blades multiplied by the hub diameter

Answer

Blade angle divided by propeller rpm at cruise power

Question 4

What is the blade angle of a propeller?

Accepted Answer

The angle between the blade chord line and the plane of rotation

Answer

The angle between the chord line and the relative airflow

Answer

The angle between the relative airflow and the plane of rotation

Question 5

What is the effect of windmilling of a propeller after engine failure?

Accepted Answer

It produces a lot of drag and can keep the engine turning

Answer

It produces extra thrust from the airflow passing through it

Answer

It has no noticeable effect on the aircraft's glide performance

Question 6

What is a constant-speed propeller?

Accepted Answer

A governor varies blade angle to hold rpm

Answer

A propeller with a fixed blade angle

Answer

A propeller geared to turn at engine speed

Question 7

What is the hub of a propeller?

Accepted Answer

The central part that holds the blades and attaches to the engine

Answer

The outer part of the blade, out towards the tip

Answer

The spinner and its backplate, which carry no load

Question 8

What is a ground-adjustable propeller?

Accepted Answer

Blade angle set only on the ground, engine stopped

Answer

Pitch changes automatically in flight to hold rpm

Answer

Blades can be feathered in flight after engine failure

Question 9

What is the purpose of the blade retention bearings in a variable-pitch hub?

Accepted Answer

To carry centrifugal load while letting blades turn

Answer

To seal oil inside the hub and stop leaks only

Answer

To drive the propeller governor from the hub

Question 10

What does an autofeather system do?

Accepted Answer

Feathers a failed engine's propeller automatically

Answer

Changes the pitch automatically for cruise

Answer

Feathers both propellers at the same time

Question 11

What happens in a constant-speed propeller governor when the engine overspeeds?

Accepted Answer

Flyweights move out; blade angle increases

Answer

Flyweights move in; blade angle decreases

Answer

Nothing happens until the pilot acts

Question 12

What is reverse pitch used for?

Accepted Answer

To produce reverse thrust for braking after landing

Answer

To increase thrust for a short take-off

Answer

To move the blades to the feathered position

Question 13

How is unfeathering usually achieved in flight on a light twin?

Accepted Answer

An accumulator or electric pump supplies oil

Answer

Diving the aircraft until the blades turn

Answer

Moving the propeller lever to feather

Question 14

What does a propeller synchroniser do?

Accepted Answer

Matches slave rpm to the master propeller

Answer

Feathers the propeller of a failed engine

Answer

Cycles the blade de-icing elements

Question 15

How is electrical power transferred to the de-icing elements on rotating propeller blades?

Accepted Answer

Through slip rings and brushes at the hub

Answer

Through a long cable wound around the shaft

Answer

By an induction coil with no contacts at all

Question 16

How is static balance of a propeller checked?

Accepted Answer

On a knife-edge or stand, it stays put

Answer

By running the engine at full power

Answer

By weighing each blade on scales

Question 17

Why must the propeller area be kept clear during engine ground runs?

Accepted Answer

A spinning propeller is nearly invisible

Answer

To keep the propeller clean

Answer

So the engine starts more easily

Question 18

Why is it important to maintain the correct blade angle settings on a multi-blade propeller?

Accepted Answer

Unequal angles cause imbalance and vibration

Answer

They affect only the paint wear

Answer

They change the engine's fuel needs only

Question 19

What is propeller blade tracking?

Accepted Answer

Checking each tip follows the same path

Answer

Measuring the blade angle at the root

Answer

Recording the propeller's flight hours

Question 20

What is done to preserve a metal propeller for long-term storage?

Accepted Answer

Clean, apply corrosion preventive, cover

Answer

Leave it uncovered outdoors

Answer

Fill the hub with water to stop seals drying