2 USSR Flight covers carried on board "Inaugural flight TUPOLEV TU-144S Moscow - Alma-Ata 1975" (TU144-75S)

The Tupolev Tu-144 supersonic jet (USSR)

The Tupolev Tu-144 is a four-engine supersonic airliner developed in the USSR by the Tupolev design bureau. Along with the Anglo-French Concorde, it is one of only two supersonic civilian aircraft to have reached production. Intended for use on Aeroflot routes, it can carry 98 to 120 passengers at speeds exceeding Mach 2 and at an altitude of 20,000 meters (65,617 feet), over a distance of 3,080 to 6,200 km depending on the version.

The prototype of the Tupolev Tu-144 first flew on December 31, 1968, becoming the first supersonic airliner, and broke the sound barrier on June 5, 1969. In June 1973, an accident involving a production aircraft during a demonstration at the Paris Air Show delayed the program's development.

The production aircraft entered service, initially as cargo and mail planes, with an inaugural flight from Moscow to Alma-Ata (Kazakhstan) on December 26, 1975. The first Moscow-Alma-Ata (Kazakhstan) route opened to passengers on November 1, 1977. A second aircraft was involved in an accident in May 1978 during a test flight, resulting in its withdrawal from passenger service.

However, it remained active as a cargo aircraft until 1983. Production ended in 1984 with a total of 16 aircraft built: one prototype, ten Tu-144S, and five Tu-144D.

One of the aircraft was restored to flying condition in 1996 as part of a program between Tupolev and NASA and was permanently retired in 1999. (source: Wikipedia)

A few rare philatelic documents, some of which have been transported on board the first flights of the Tupolev TU-144, bear witness to the era of supersonic civil aviation in the Soviet Union (1968-1984).