DOUBLE COUNTER-ROTATING PROPELLER ELECTRIC MOTORS

It is an engine with two counter-rotating propellers on the same axis.

Here is a brief explanation of the aircraft engine: when an engine is running, it produces what is known as torque, and the propeller generates a spiral airflow.

Both elements must be controlled so that the aircraft remains controllable.

This is achieved through “Sturz,” which means the engine is tilted downward relative to the longitudinal axis—by just a few degrees.

“Seitenzug” is a shift of the engine axis to the left in the direction of flight. Again, just a few degrees.

If the engine is installed parallel to and horizontal with respect to the longitudinal axis, this can result in increased lift when air strikes the wing.

Since the airflow moves in a rotational direction along the fuselage, this can affect elevator and rudder control in short-fuselage aircraft. This is prevented by the offset.

With a twin-propeller engine, torque is eliminated and the airflow should be straight.

This ensures more stable flight performance and better control of the aircraft.

Those who feel at home in the F3A scene might want to give some thought to purchasing this engine.

Text and photos of model airplanes: Wolf Völler

Engine photos: Internet