France has the singular distinction among nations of the world in having built and flown a ramjet-powered prototype of a supersonic interceptor fighter. The experimental aircraft Nord 1500 Griffon, a hybrid between ramjet and turbojets, then epitomized the most ambitious project of its time upon entering the stratospheric realm of speed.
The roots of the Nord 1500 Griffon lie in the late 1940s in preliminary studies for a high-speed delta-wing aircraft. Only in the mid-1950s did the project start to gain real momentum. Design studies for a high-performance manned interceptor in response to a French Air Ministry specification in August 1953 led to a pair of prototypes being ordered. The Griffon project was started to carry on another of Nord’s delta designs, the 1402 Gerfaut, by Jean Galtier.
The Griffon was a creation of highly advanced aeronautical engineering, featuring a delta-wing arrangement combined with a fixed canard configuration. In many ways, the lightweight metal alloy airframe was dictated by the shape of its dual-engine configuration. The cockpit sat almost directly above the large oval air intake that fed air to both the turbojet and ramjet engines.
The prototype, designated 1500-01 “Griffon I,” made its maiden flight on 20 September 1955, powered solely by an Atar 101F G2 afterburning turbojet engine. This first flight reached a maximum speed of Mach 1.17, far below the Mach 2 performance expected. Nevertheless, the Griffon I served to give data for the project. The first aircraft took its last flight on 16 April 1957 but was never fitted with the planned ramjet powerplant.
The second prototype, named “Griffon II,” was the real star of the program. It was fitted with the Nord Strato-Reacteur ramjet unit offering 15,290 lbs of thrust, a capability almost twice that of a turbojet. Griffon II first flew on January 23, 1957, and by December of that year, it had recorded a speed of Mach 1.85. It finally achieved the sought-after Mach 2 in October 1958, although the aircraft could structurally only reach as high as Mach 2.1. The Griffon II was also displayed at the Paris Air Show in that year of 1959, which reflected its technological stature.
The Griffon program also had its share of huge setbacks. The unavailability of materials in those days meant very high temperatures experienced on the airframe. The ramjet was also problematic at mid-range speeds. More significant setbacks included potential that was further overshadowed by simpler, cheaper jet aircraft like the Dassault Mirage III.
June 5, 1961: The Griffon program officially canceled minus a total of 337 flights. The project greatly advanced my understanding of high-speed flight and set the groundwork for future designs. A proposal for a Mach 3-capable “Super Griffon” was made, but it never advanced past the study phase.
Today, the second prototype of the Nord 1500 Griffon is on display at the Musée de l’Air et de l’Espace at Le Bourget Airport, near Paris, acting as a reminder of France’s pioneering efforts into supersonic aviation.