According to aviation authors Doug Dildy and Pablo Calcaterra, Dassault discreetly provided the jigs, fixtures, and a large quantity of airframe components to Israel via an industrial consortium of Israeli aerospace company Israel Aircraft Industries and American aviation firm North American Rockwell, who were claimed to have been sold a manufacturing licence in January 1968. Reportedly, the first bare airframes, featuring no weapons, electronics, ejection seat, or engine included, had been delivered directly from Dassault in France. Dildy and Calcaterra claimed that detailed information on the aircraft's Atar engine was obtained via Swiss industrial manufacturer Sulzer, who had produced the engine for Switzerland's own Mirages; between these blueprints and possessing several Atar engines of the IAF's existing Mirages to reverse engineer, Israel was able to independently manufacture its own engines.