What type of propulsion did the Wright brothers’ 1903 Flyer use?

The Wright brothers’ 1903 Flyer used two pusher propellers for propulsion.

The propellers were mounted behind the wings and pushed the aircraft forward, which is why they are called pusher propellers. A single engine drove both propellers through chains adapted from bicycle technology. The brothers designed the propellers themselves after studying the problem mathematically rather than treating them as simple rotating airfoils.

This arrangement differs from the tractor-propeller layout used by many later aircraft, in which the propeller is mounted in front of the engine or wing and pulls the airplane forward. The Flyer’s two propellers rotated in opposite directions to counteract torque. Its propulsion system was therefore closely connected to the Wrights’ bicycle-building experience and their practical approach to solving mechanical problems.