as the A300B1. On 3 September 1970, Air France signed a letter of intent for six A300s, marking the first order to be won for the new airliner. In the aftermath of the Paris Air Show agreement, it was decided that, in order to provide effective management of responsibilities, a Groupement d'intérêt économique would be established, allowing the various partners to work together on the project while remaining separate business entities. On 18 December 1970, Airbus Industrie was formally established following an agreement between Aérospatiale (the newly merged Sud Aviation and Nord Aviation) of France and the antecedents to Deutsche Aerospace of Germany, each receiving a 50 per cent stake in the newly formed company. In 1971, the consortium was joined by a third full partner, the Spanish firm CASA, who received a 4.2 per cent stake, the other two members reducing their stakes to 47.9 per cent each. In 1979, Britain joined the Airbus consortium via British Aerospace, which Hawker Siddeley had merged into, which acquired a 20 per cent stake in Airbus Industrie with France and Germany each reducing their stakes to 37.9 per cent. Prototype and flight testing Airbus Industrie was initially headquartered in Paris, which is where design, development, flight testing, sales, marketing, and customer support activities were centered; the headquarters was relocated to Toulouse in January 1974. The final assembly line for the A300 was located adjacent to Toulouse Blagnac International Airport. The manufacturing process necessitated transporting each aircraft section being produced by the partner companies scattered across Europe to this one location. The combined use of ferries and roads were used for the assembly of the first A300, however this was time-consuming and not viewed as ideal by Felix Kracht, Airbus Industrie's production director. Kracht's solution was to have the various A300 sections brought to Toulouse by a fleet of Boeing 377-derived Aero Spacelines Super Guppy aircraft, by which means none of the manufacturing sites were more than two hours away. Having the sections airlifted in this manner made the A300 the first airliner to use just-in-time manufacturing techniques, and allowed each company to manufacture its sections as fully equipped, ready-to-fly assemblies. In September 1969, construction of the first prototype A300 began. On 28 September 1972, this first prototype was unveiled to the public, it conducted its maiden flight from Toulouse–Blagnac International Airport on 28 October that year. This maiden flight, which was performed