France holds a special place in aviation history as the only country to have developed and flown a ramjet-powered, Mach-plus fighter prototype. The Nord 1500 Griffon was born of a requirement by the French Air Ministry for a high-performance, manned interceptor; two prototypes were ordered in August 1953. This project truly belonged to the very leading edge of technology for the time, with an advanced delta wing and fixed canard configuration.
The Nord 1500 Griffon originally came from studies on delta-wing aircraft made in the late 1940s for flying at high speeds. It wasn’t until the mid-1950s for the project to really take off. Primarily, the a/c was made from lightweight metal alloys. The shape largely came from the twin-engine configuration. The cockpit was placed almost directly above the large oval air intake that fed the turbojet and ramjet engines.
The Griffon was a testbed fighter and thus held a hybrid ramjet/turbojet powerplant. A fairly low-powered turbojet was only used for takeoff and low-speed maneuvering, since ramjet engines cannot run at zero airspeed. Once airborne, acceleration up to more than 600 mph allowed the ramjet to start running, and the aircraft would accelerate to over Mach 2.
The first prototype was the Griffon I, which was powered by an Atar 101F G2 afterburning turbojet alone. It first flew on September 20, 1955, and reached a top speed of Mach 1.17. Although far from the Mach 2 performance wanted, this prototype brought very useful information about the flying body and aerodynamics. The prototype Griffon I flew until April 16, 1957, but was never fitted with its intended ramjet engine.
Griffon II was the only entrant into the Griffon test programme to feature the ramjet engine. It carried the Atar 101 F series afterburning turbojet engine, exhausted through a larger-diameter port under the tail fin. An early-form computer system was brought in to more capably manage fuel to the ramjet unit. The first flight of the Griffon II was on January 23, 1957, and by December, it had reached Mach 1.85. October 1958 finally saw Mach 2 reached, though the airframe ultimately limited top speeds to Mach 2.1. The Griffon II also flew at the 1959 Paris Air Show.
Interest in the Griffon, however, waned by the end of the decade. The program was officially canceled on 5 June 1961 after a total of 337 flights. Griffon prototypes contributed massively to high-speed flight concepts and theories for future designs. Nord Aviation had initiated studies for a Mach 3 version, the “Griffon III” or “Super Griffon,” but nothing came of it.
Today, the second prototype of the Nord 1500 Griffon is preserved in the Musée de l’Air et de l’Espace at Le Bourget Airport near Paris as a token and memorandum of France’s initiatives into pioneering aviation technology.