Aluminum and Composite Propellers

Question 1

are the most widely used propeller today

Answer 1

Aluminum Prop

Question 2

What is the advantage of aluminum prop to wooden prop?

Answer 2

thinner more efficient airfoils and can handle higher horsepower
requires less maintenance and are easier to repair along with being more cost effective

Question 3

Aluminum propellers can be?

Answer 3

either fixed pitch or variable pitch

Question 4

why is aluminum prop heat treated?

Answer 4

to relieve internal stresses and balanced both vertically and horizontally

Question 5

What do you call the chemical treating of the propeller?

Answer 5

Alodining

Question 6

What do you call the electrochemical treating of the propeller?

Answer 6

Anodizing

Question 7

Different types of Propeller tip

Answer 7

Round tip
Square tip or Klip tip
Scimitar sweptback
Q-tip

Question 8

Type of propeller tip that have a large area of rotation or arc and no advantage for tip disturbances

Answer 8

Round tip

Question 9

Type of propeller tip that can be shorter than rounded tip and are able to run at a lower rpm which makes them quieter

Answer 9

Square tip or klip tip

Question 10

Type of propeller tip that reduces tip vortices and drag which allows for a higher speed operation

Answer 10

Scimitar sweptback

Question 11

Type of propeller tip that have a 90 degree bend at the tip towards the face which makes them quieter and also reduces tip vortices

Answer 11

Q-tip

Question 12

Disadvantages of aluminum propellers

Answer 12

Heavier compared to wooden propellers
Susceptible to vibration with a potential for damage
Higher initial cost
Corrosion potential
Higher risk of failure of unrepaired damage or dressing

Question 13

Types of Propeller Mounting

Answer 13

Splined shaft
Tapered shaft
Flange mount

Question 14

are fabricated in a mold by laminating layers of composite materials over a core of either wood, honeycomb or rigid foam and a reinforcing shank

Answer 14

Composite propeller

Question 15

What materials can be used for composite propellers?

Answer 15

fiberglass or carbon fiber and aramid fiber

Question 16

The leading edge of composite prop is often protected from erosion with a ___ ____ which can be applied during the manufacture process or after the blade is cured

Answer 16

metal strip

Question 17

What do they put in the leading edge of a composite prop for superior abrasion protection?

Answer 17

Nickel or stainless steel leading edge shields

Question 18

What do they coat in a composite prop to protect the entire blade from erosion as well as ultraviolet damage

Answer 18

Polyurethane paint

Question 19

Lightning protection is accomplished by?

Answer 19

adding a conductor to the propeller and attaching it to the metal root

Question 20

How do they statically balanced composite prop?

Answer 20

By adding lead wool to a centrally located balance tube in the metal blade shank