The two seat, open cockpit C.251 was designed to replace the ubiquitous Caudron C.59, dating from 1922, as an intermediate trainer aircraft.
[1] It was powered by a 180 kW (240 hp) Lorraine 7Me Mizar seven cylinder radial engine which had a Townend ring type cowling and drove a two blade metal propeller with a conical spinner.
The forward cockpit was under the upper wing trailing edge where a slight cut-out improved the pupil's upward view.
The C.251s empennage was conventional, with tailplane and elevators mounted on top of the fuselage and having a planform similar to the wins, apart from a cut-out for rudder movement.
The fin profile was a shallow triangle; the rudder continued its upper line to a rounded tip and straight, vertical trailing edge.