Propeller Design ChallengePropeller Design Challenge

First FlightFirst Flight

On December 17, 1903 the Wright brothers On December 17, 1903 the Wright brothers took flight on the sands of Kitty Hawk, North took flight on the sands of Kitty Hawk, North Carolina.Carolina.

The flight was only about 12 seconds long The flight was only about 12 seconds long and traveled 120 feet.and traveled 120 feet.

Propellers and Newton’s : Propellers and Newton’s : Third LawThird Law

When one body exerts force on a second When one body exerts force on a second body, the second body exerts an opposite body, the second body exerts an opposite yet equal force.yet equal force.

In the case of propeller driven air plane, a In the case of propeller driven air plane, a set of spinning blades (body #1) exerts force set of spinning blades (body #1) exerts force on air molecules (body #2), and those on air molecules (body #2), and those molecules exert an equal and opposite molecules exert an equal and opposite amount of force on the blades.amount of force on the blades.

Pushing Air: Thrust vs. DragPushing Air: Thrust vs. Drag

Air that is pushed back, parallel to the shaft, Air that is pushed back, parallel to the shaft, creates an opposite force on the propeller creates an opposite force on the propeller called called Thrust. Thrust. Which pushes the propeller Which pushes the propeller forward.forward.

Air that is pushed perpendicular to the shaft Air that is pushed perpendicular to the shaft creates an opposite force on the propeller creates an opposite force on the propeller that is called that is called Drag. Drag. Which resists the Which resists the propellers rotation. propellers rotation.

Wright Brothers:Wright Brothers:Contribution to Propeller DesignContribution to Propeller Design

The Wright brothers spent months The Wright brothers spent months researching existing literature on propeller researching existing literature on propeller design.design.

The eventually came up with the concept of The eventually came up with the concept of curving the wing of the propeller.curving the wing of the propeller.

This create horizontal This create horizontal lift. Which increase lift. Which increase the output of the propeller.the output of the propeller.

PropellersPropellers