Soyuz 7K-OK

The Soyuz 7K-OK was the first generation of Soyuz spacecraft and flew between 1967 and 1971. It carried a crew of up to three without space suits and is recognisable by its bent solar panels and the Igla automatic docking system, which needed special radar antennas. It began as an Earth orbit test variant of the 7K-LOK lunar spacecraft, lacking only the larger antenna for lunar distances, and early flights carried an empty external toroidal fuel tank that was later removed. It was used for the first ferry flights to the Salyut space station programme. It achieved the first uncrewed automated docking, between Kosmos 186 and Kosmos 188 in 1967, the first docking between two crewed spacecraft, Soyuz 4 and Soyuz 5, and the first crew transfer to a space station, Soyuz 11 and Salyut 1 in 1971. It also caused the only deaths of the Soyuz programme, on Soyuz 1 and Soyuz 11.