to the passage below and then answer the question afterwards in the same language as the passage: Passage: The design work was supported by a preceding research program studying the flight characteristics of low ratio delta wings. A supersonic Fairey Delta 2 was modified to carry the ogee planform, and, renamed as the BAC 221, used for flight tests of the high speed flight envelope, the Handley Page HP.115 also provided valuable information on low speed performance.Construction of two prototypes began in February 1965: 001, built by Aérospatiale at Toulouse, and 002, by BAC at Filton, Bristol. Concorde 001 made its first test flight from Toulouse on 2 March 1969, piloted by André Turcat, and first went supersonic on 1 October. The first UK-built Concorde Filton flew from RAF Fairford Regional on 9 April 1969, piloted by Brian Trubshaw. Both prototypes were modified to carry the ogee planform, and, renamed as the BAC 221, used for flight tests of the high speed flight envelope, the Handley Page HP.1
2 June 1972