Nord 1500 Griffon
| Company type | State-owned company |
|---|---|
| Industry | Aerospace |
| Predecessor | SFECMAS, SNCAN |
| Fate | Merged into other entities (implied) |
| Headquarters | France |
Area served | Aerospace industry |
Key people | Jean Galtier (chief designer) |
| Products | Aircraft, including Nord 1500 Griffon |
| Owner | State-owned |
Nord 1500 Griffon represents a French experimental interceptor powered by a ramjet, developed and constructed by the state-owned firm Nord Aviation. Conceived as a Mach 2 successor to the supersonic Nord Gerfaut, the Griffon incorporated a pioneering dual propulsion setup, combining a turbojet for initial takeoff and acceleration with a ramjet engine optimized for sustained high-speed flight.
The initial prototype, Griffon I, took to the skies in 1955, achieving Mach 1.3 without engaging the ramjet, primarily serving aerodynamic and systems validation purposes. Flight trials concluded following Griffon II’s inaugural flight in 1957, which reached Mach 2.19 and established a small closed-course speed record in 1959. As recorded by the Fédération Aéronautique Internationale, it held the official airspeed record from October 5 to 31, 1959, at 1,441.6 mph (2,320 km/h), with Maj. André Turcat at the controls. The aircraft was withdrawn from service in 1961 and is currently exhibited at the Musée de l'air et de l'espace near Paris.
Development and description
The Griffon project emerged from government-funded studies focused on delta and swept-wing designs. Arsenal de l'Aéronautique contributed by constructing the wooden glider Arsenal 1301, which experimented with various wing shapes and supplied critical data influencing the Gerfaut’s design.
Jean Galtier, chief designer at SFECMAS, initiated three interceptor concepts: the 1400 (which evolved into the Nord Gerfaut), the 1500 (Griffon), and an unpursued 1910 variant featuring twin large ramjets. Galtier aimed for the Griffon to succeed Gerfaut as a Mach 2-capable aircraft. Following SFECMAS’s merger with SNCAN into Nord Aviation, the project was renamed from SFECMAS 1500 Guépard.
On August 24, 1953, a contract was placed for two prototypes intended purely for research without combat equipment; this agreement was finalized in 1955. Although ultimately envisioned as a lightweight interceptor operable from grass airstrips, these models primarily gathered experimental insights.
Galtier designed a straight-through air duct with a single-seat cockpit positioned above a semi-circular ventral intake. The fuselage incorporated delta wings derived from the Gerfaut and featured a swept vertical tail with rudder. To counteract nose-down pitching tendencies of delta wings at transonic speeds, small triangular canards were installed near the cockpit. The tricycle landing gear retracted into both wings and beneath the air intake.
A significant advancement was its dual-propulsion concept: an afterburning SNECMA Atar 101G21 turbojet allowed independent takeoffs, while thrust above roughly 1,000 km/h (600 mph) was produced by a ramjet engine. To reduce development risks, Griffon I initially operated solely on turbojet power; integration of the ramjet occurred subsequently.
Flight testing
The Griffon I completed its first flight on September 20, 1955, with André Turcat as pilot. Early tests indicated insufficient power output, exacerbated by cancellation of the planned ramjet system. Nevertheless, it achieved Mach 1.15 during its first supersonic flight on January 11, 1956. Subsequently, the air intake was enlarged—likely coinciding with installation of the more potent Atar 101E engine—enabling maximum speeds of Mach 1.3 at approximately altitude. Although engine thrust declined beyond , handling characteristics remained highly favorable. After sustaining nose gear collapse during taxiing on June 19, it resumed flight operations on July 26. The Griffon I bore close resemblance to its ramjet-equipped successor Griffon II, differing mainly in intake dimensions and possessing a unique two-position exhaust nozzle specific to Griffon I. It was retired on April 16, 1957.
The Griffon II paired an Atar 101E-3 turbojet with a Nord-designed ramjet. Accommodating the ramjet’s diameter necessitated lengthening and widening of the aft fuselage along with enlargement of the ventral air intake to increase airflow capacity. Its maiden flight occurred on January 23, 1957, followed by its first supersonic run on April 6. Initial performance was underwhelming; it failed to surpass Griffon I’s Mach 1.3 due to inadequate air supply feeding the ramjet. After further enlargement of the intake system, speeds reached Mach 1.85 during subsequent flights. On October 5, 1959, Griffon II established a speed record of , peaking at Mach 2.19 at on October 13 under Turcat’s control. Earlier that year on February 25, Turcat exceeded previous world closed-circuit speed records by over , achieving , earning him the Harmon Trophy. The United States Air Force (USAF) contributed partial funding for testing until 1960; no flights were conducted between February and July that year, with final flight logged on June 5, 1961.
Testing revealed several technical difficulties including severe kinetic heating and elevated ramjet exhaust temperatures damaging tailpipe components. The aircraft’s Duralumin skin also endured thermal stresses during operations. Ramjet control proved challenging since it could only be switched on or off via fuel-to-air ratio adjustments without throttle modulation capability. Pilots commended Griffon II for excellent handling across all speeds; its ramjet ignited reliably over a broad speed range while its intake efficiently managed varying angles of attack. Its capacity to sustain acceleration during maneuvering contributed significantly to setting closed-circuit speed records.
Variants
- SFECMAS 1500 Guépard
- This was the original title and designation used during the preliminary design phase at SFECMAS.
- Nord 1500-01 Griffon I
- The initial prototype powered exclusively by the SNECMA Atar 101F afterburning turbojet engine, which was a component of the intended turbo-ramjet propulsion system.
- Nord 1500-02 Griffon II
- The follow-up model incorporating the finalized turbo-ramjet engine configuration.
Operators
Aircraft on display
A Nord 1500 Griffon II is showcased at the Musée de l'air et de l'espace located in Le Bourget, close to Paris.
Bibliography
- Buttler, Tony and Jean-Louis Delezenne. X-Planes of Europe: Secret Research Aircraft from the Golden Age 1946-1974. Manchester, UK: Hikoki Publications, 2010.
- Carbonel, Jean-Christophe. French Secret Projects 1: Post War Fighters. Manchester, UK: Crecy Publishing, 2016
- El-Sayed, Ahmed F. Fundamentals of Aircraft and Rocket Propulsion. Springer, 2016. .
Further reading
External links
- Overview of the Griffon program (in French)
- Griffon II (in French)
- Griffon derivatives (in French)
- EADS - Nord 1500
- Turbo-ramjet genesis (in French)