Propeller

propeller is a set of long blades attached to a hub in the center. The job of a propeller is to change the turning force, or torque, of an engine into thrust. Thrust is the force that moves an aircraft through the air.

Propellers and Engines

More than 100 years ago, the first air­planes were powered through the air by propellers. When the jet engine was invented, it looked like the propeller’s days might be over. Even in the age of jets and rockets, however, propellers are still widely used. A piston engine driv­ing a propeller is still the best way to power a small plane today.

There also are many turbine-powered planes with propellers. A turboprop engine runs a lot faster than the best speed for the propeller it controls, so the engine and propeller are connected by a gearbox. Just as a car’s gearbox lets its engine and wheels run at different speeds, a turboprop’s gearbox allows the engine to run at its ideal speed and the propeller to spin more slowly.