Boeing 707 center section tanks. Its first flight was on January 11, 1958; 69 turbojet 707-320s were delivered through January 1963, the first passengers being carried (by Pan Am) in August 1959. The 707-420 was identical to the −320, but fitted with Rolls-Royce Conway 508 (RCo.12) turbofans (or by-pass turbojets as Rolls-Royce called them) of 18,000 lb (79 kN) thrust each. The first announced customer was Lufthansa. BOAC's controversial order was announced six months later, but the British carrier got the first service-ready aircraft off the production line. The British Air Registration Board refused to give the aircraft a certificate of airworthiness,
1977 Dan-Air Boeing 707 crash The crack found in the failed stabiliser after the accident was thought by investigators unlikely to have been detectable using normal testing means, such as fluorescent dye. It was also thought that the crack had been present for at least 6,000 flight hours before the accident, and before the aircraft had been acquired by Dan-Air from Pan Am. Inspections of the Boeing 707-300 fleet, made as a result of the crash, found another 38 aircraft with similar cracks. </div> 1977 Dan-Air Boeing 707 crash The 1977 Dan-Air/IAS Cargo Boeing 707 crash was a fatal accident involving a Boeing 707-321C cargo