Castel-Mauboussin CM Jalon
The Castel-Mauboussin CM Jalon or Fouga Jalon two seat glider was designed in France towards the end of World War II for aerodynamic research, providing enough lift and space for measuring instruments and an operator. Two were built.
Design and development
The Jalon was designed and built specifically to the requirements of the Groupement Français pour le Developpement des Researches Aéronautiques, who wanted a glider carrying an observer and electronic equipment for in-flight aerodynamic measurements. To this end, the Jalon could carry some 50 kg of instrumentation. It was a wooden aircraft with a mid set cantilever wing built around a single spar and covered with plywood skin. The wing had a central, constant chord section and tapered panels beyond half span, with rounded wing tips.The fuselage was a wooden monocoque of oval cross-section which tapered constantly to the tail from a rather bulbous nose. The tandem cockpits were covered by a long, continuously glazed, multi-framed canopy without a windscreen step or other break in the smooth upper fuselage line. The observer's section, split into two by the wing spar, was unusually long to accommodate his instruments; he also had a pair of circular windows on each side, looking out under the wing root. The Jalon's tailplane was mounted a little above the fuselage on a shallow dorsal step, positioned ahead of the narrow chord fin. Both elevators and the generous, deep rudder were horn balanced; the rudder also carried a trim tab. There was a nose skid and monowheel undercarriage, the wheel semi-recessed at the end of the skid.