AMT 1103 AIRCRAFT PROPELLER Reviewer - Roble

General principles, nomenclature, forces, and classifications of aircraft propellers based on the AMT 1103 lecture notes.

What does a propeller convert engine power into, regardless of the engine type?

Thrust

Most modern transport category aircraft are powered by what types of engines?

Turboprop or turbofan engines

What specific new airfoil shapes and blade configurations are used in modern propellers?

Laminar flow symmetrical airfoils and scimitar-shaped blades

What is the central metal assembly that holds the propeller blades together and attaches to the engine shaft?

Hub

Which side of the propeller blade faces toward the back of the aircraft and creates the high-pressure area?

Blade Face

Which side of the propeller blade faces forward and creates the low-pressure area to generate thrust?

Blade Back

What is the thick rounded portion of the blade nearest to the hub that provides structural strength?

Shank

Which part of the propeller blade is the circular metallic part attached inside the hub?

Blade Root

What is the outermost end of the propeller blade located furthest from the hub?

Blade Tip

Which part of the propeller blade cuts through the air first during rotation?

Leading Edge

Where does air reconnect and leave the blade surface smoothly to minimize drag?

Trailing Edge

Which force acts as an outward pulling force and is $7,500$ times the weight of the propeller?

Centrifugal Force

Which force bends the propeller forward at the tips?

Thrust Bending Force

Which force bends the blade in the opposite direction of rotation due to air resistance?

Torque Bending Force

Which force acts to increase a propeller's blade angle?

Aerodynamic Twisting Force

What effect does Centrifugal Twisting Force have on the propeller's blade angle?

It tends to decrease the blade angle

What is the term for the theoretical distance a propeller travels forward in one revolution?

Propeller Pitch

What is the ideal pitch achievable in one revolution if conditions are perfect?

Geometric Pitch

What is the actual pitch achievable in one revolution with external forces acting against the propeller?

Effective Pitch

What is the difference lost between the geometric pitch and the effective pitch?

Slip

Where are tractor propellers mounted on an aircraft?

At the front of an engine

Which type of propeller is mounted on the aft (rear) end of an engine and is mainly used on seaplanes?

Pusher Propellers

In fixed-pitch propellers, which pitch is optimized for takeoff and climb?

Climb Pitch

Which pitch setting in a fixed-pitch propeller is optimized for high-speed and high-altitude flight?

Cruise Pitch

According to the lecture, a high blade angle is associated with which type of pitch?

Cruise pitch

During which decades were ground-adjustable propellers most commonly used?

The $1920s$ & $1940s$

Which propeller classification allows the operator to change the blade angle while in the air?

Controllable-Pitch Propeller

Which device automatically adjusts the blade angle in a constant-speed propeller to maintain a set RPM?

Governor

Which propeller type allows blades to be set to a negative angle to produce reverse thrust?

Reversible-Pitch Propellers

When is a feathering propeller typically utilized?

Only if the engine fails

What is the position of the blades when a propeller is feathered?

The leading edge of each blade is pointed forward towards the wind