Russian propaganda outlet RT has a story [rt.com] looking back at the history of the Soyuz-U rocket, [wikipedia.org] on the occasion of its final launch. According to the story, the Soyuz-U has flown 788 or 789 times, the first mission taking place in 1973 when it was used to loft "a Soviet military surveillance satellite" and the most recent carrying
[...] the Progress MS-05, a freighter carrying 2.5 tons of miscellaneous cargo – fuel, food, water, sanitation, oxygen and air, as well as spare parts, supplies and experiment hardware – to the International Space Station (ISS).
The story calls it "the longest-serving rocket in history."
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