Aluminum and Composite Propellers Flashcards
are the most widely used propeller today
Aluminum Prop
What is the advantage of aluminum prop to wooden prop?
thinner more efficient airfoils and can handle higher horsepower
requires less maintenance and are easier to repair along with being more cost effective
Aluminum propellers can be?
either fixed pitch or variable pitch
why is aluminum prop heat treated?
to relieve internal stresses and balanced both vertically and horizontally
What do you call the chemical treating of the propeller?
Alodining
What do you call the electrochemical treating of the propeller?
Anodizing
Different types of Propeller tip
Round tip
Square tip or Klip tip
Scimitar sweptback
Q-tip
Type of propeller tip that have a large area of rotation or arc and no advantage for tip disturbances
Round tip
Type of propeller tip that can be shorter than rounded tip and are able to run at a lower rpm which makes them quieter
Square tip or klip tip
Type of propeller tip that reduces tip vortices and drag which allows for a higher speed operation
Scimitar sweptback
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
Q-tip
Disadvantages of aluminum propellers
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
Types of Propeller Mounting
Splined shaft
Tapered shaft
Flange mount
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
Composite propeller
What materials can be used for composite propellers?
fiberglass or carbon fiber and aramid fiber
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
metal strip
What do they put in the leading edge of a composite prop for superior abrasion protection?
Nickel or stainless steel leading edge shields
What do they coat in a composite prop to protect the entire blade from erosion as well as ultraviolet damage
Polyurethane paint
Lightning protection is accomplished by?
adding a conductor to the propeller and attaching it to the metal root
How do they statically balanced composite prop?
By adding lead wool to a centrally located balance tube in the metal blade shank
