|Nord Aviation Nord-500|
The Nord 500 was a single seat, company funded research aircraft. Its mission was to evaluate principles of the Tilt Duct propulsion concept for VTOL aircraft. The enclosed cabin contained an ejection seat. Two 317hp Allison T63-A-5A (or Allison T63-A5T, or 250-C18, depending on the source) turboshaft engines were located side by side in the rear part of the fuselage. They drove two 1.5m diameter props through interconnected shafts. Moveable vanes in the propeller slipstream controlled the duct positions aerodynamically. There were no other mechanical controls for rotating the ducts. The ducts tilted, along with a short section of wing. During hover, control in roll was by differential thrust, while control in pitch was by collective tilting of the ducts. There was no provision for attitude control of the fuselage because the ducts pivoted freely. The intended top speed was 218 miles per hour.
The first prototype was completed in Spring 1967 and was used for mechanical and ground tests. The second prototype made its first tethered flight during July 1968.
Nord merged with the Aerospatiale Corporation in about 1970, and the aircraft became known as the Aerospatiale N 500. Although a more sophisticated and more powerful version was in planning, all efforts on the Nord 500 appear to have stopped by 1971.
S.Markman & B.Holder "Straight Up: A History of Vertical Flight", 2000