On May 4th, 1971 the prime crew of Soyuz 11 was confirmed to be Leonov, Commander; Kubusov, Flight Engineer; and Kolodin, Research Engineer. Their assignment was to spend between 30 and 45 days on board Salyut 1.
… There was no provision for the possibility of undocking if the entire docking cycle had not been executed …
“They can’t approach at that rate,” fretted Mishin. “Why aren’t you doing anything? Tell the crew what to do!” “We don’t need to do anything; deceleration will begin now,” Rauschenbach reassured Mishin.
The objective of the Soyuz 10 mission was to deliver and return to earth the first crew of Salyut 1. The Soyuz was to hard dock with Salyut 1 and then the crew was to transfer internally to the station.
The Vulcan device consisted of two major units. The first unit included various welding devices and a turn-table with samples of metals to be welded. The second unit consisted of an electric power pack, a protective shield which covered the welding unit, and a remote control console.
Finally, on April 25, 1969 during a meeting of the Soyuz State Commission, it was decided that the solo and docking flights outlined for 1969 by design bureau OKB-1 would be combined into a joint flight of three spacecraft. The plan was to fly Soyuz 6, 7, and 8 together in August of 1969; Soyuz 7 and 8 would dock and 6 would rendezvous with the docked pair and take pictures of it as well as perform a welding experiment.