The Rhein-Flugzeugbau RF-1 was a prototype channel wing aircraft.

The "channel" is an airfoil-shaped section along the lower arc of the rearward propeller that produces additional lift from the propwash.

[2] The aircraft had the unique shape to facilitate a channel wing design.

The fuselage was composed of welded steel tubing with a composite skin.

The landing gear was electrically retractable.