Give an explanation of why the Nord Griffon1500 was special for its time, what sort of things it was designed to achieve and whether or not it was a success.

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gsenviro eNotes educator| Certified Educator

Nord Griffon 1500 was an experimental aircraft, in France in 1950s, designed to test twin turbojet-ramjet power unit. The overall project was aimed at providing a Mach 2 aircraft to French Air Force, with the primary role of light interceptor.

The plane was designed to use turbojet for unassisted take-off and ramjet (produces extra thrust at high speeds) for cruise. The wings of the plane had a delta configuration, with 60 degrees of sweepback on the leading edge. The plane was fitted with evelons (for pitch control) and roll ducts. It was made from light alloys and was designed for single pilot. 

The plane achieved the necessary speed, even with an under-powered engine. Originally designed with 4100 kgf thrust turbojet, the initial test flight had 3800 kgf thrust engine. This plane, Griffon I, achieved a maximum speed of 1.7 Mach. With redesigning and a 3500 kgf thrust engine, Griffon II reached a maximum speed of 2.19 Mach. 

Although speed requirements were met (verifying the success of basic design), the planes suffered from kinetic heating and unstable ramjet at medium speeds. 

Hope this helps.