remains the only museum in the world where the Tu-144 and Concorde are on display together. Incidents and accidents Paris Air Show crash At the Paris Air Show on 3 June 1973, the development program of the Tu-144 suffered severely when the first Tu-144S production airliner (reg 77102) crashed. At the end of the officially approved demonstration flight, which was an exact repeat of the previous day's display, instead of landing as expected the aircraft entered a very steep climb before making a violent downwards manoeuvre. As it tried to recover the aircraft broke apart and crashed, destroying 15 houses and killing all six people on board the Tu-144 and eight more on the ground. Gordon et al. state that the flight crew had departed from the approved flight profile for the display, a serious offense in itself. They were under instructions to outperform the Concorde display by all means. During the unapproved, and therefore unrehearsed manoeuvres, the stability and control augmentation system was not operating normally. If it had been, it would have prevented the loads that caused the port wing to fail. A popular Soviet theory for the crash was that the Tu-144 tried to avoid a French Mirage chase-plane that was attempting to photograph its canards, which were very advanced for the time, and that the French and Soviet governments colluded with each other to cover up such details. The flight of the Mirage was denied in the original French report of the incident, perhaps because it was engaged in industrial espionage. More recent reports have admitted the existence of the Mirage (and the fact that the Soviet crew was not told about the Mirage's flight), though not its role in the crash. The official press release did state: "though the inquiry established that there was no real risk of collision between the two aircraft, the Soviet pilot was likely to have been surprised." Another theory relates to deliberate misinformation on the part of the Anglo-French design team. The main point of this theory is that the Anglo-French team knew the Soviet team was planning to steal the design plans of Concorde, and allegedly passed ersatz (substituted) blueprints with a flawed design to the Soviets. The case, it is claimed, contributed to the imprisonment by the Soviets of Greville Wynne in 1963 for spying. Wynne was imprisoned on 11 May 1963 and the development of the Tu-144