Commander Volynov shuttled the EVA crew of Yeliseyev and Khrunov into earth orbit. A day later Soyuz 4 docked with Soyuz 5. The Soyuz 4 active spacecraft was equipped with a long docking probe, designated 'Shtir'. The Soyuz 5 target spacecraft was equipped with the 'Konus' receptacle. The symbology lead Volynov to joke that he 'was being raped' when the hard docking was accomplished. Khrunov and Yeliseyev transferred to and returned in Soyuz 4, the feat they had hoped to accomplish in the cancelled Soyuz 2 flight almost two years earlier. Officially the flight conducted scientific, technical and medico-biological research, checking and testing of onboard systems and design elements of space craft, docking of piloted space craft and construction of an experimental space station, transfer of cosmonauts from one craft to another in orbit.
Volynov remained behind to live through the most unbelievable re-entry in the history of spaceflight. The service module of the Soyuz failed to separate after retrofire. Once the Soyuz started reaching the tendrils of the atmosphere, the combined spacecraft sought the most aerodynamically stable position - nose forward, with the heavy descent module with its light metal entry hatch at the front, the less dense service module with its flared base to the back. Luckily the struts between the descent and service modules broke off or burned through before the hatch melted through and the descent module righted itself, with the heat shield to the rear, before being consumed. Due to a failure of the soft-landing rockets the landing was harder than usual and Volynov broke his teeth. Recovered January 18, 1969 07:58 GMT.
Soyuz 4 successfully lifted off from Launch Complex 31 the next day. 24 hours later it was followed by Soyuz 5 from Launch Complex 1. After the problems with Soyuz 3, a first-revolution docking was not planned. Instead the automatic rendezvous began on 16 January at 13:37 GMT on the 34th revolution of Soyuz 4 and the 18th revolution of Soyuz 5. At 100 m distance Shatalov took over manual control of Soyuz 4 and guided the spacecraft to an accurate docking on the first attempt at 14:20 GMT.
On the 35th revolution of the earth Khrunov and Yeliseyev,left Soyuz 5 and in one hour spacewalked to Soyuz 4. Soyuz 4 and 5 separated after 4 hours and 35 minutes docked together.
Volynov remained behind for what was undoubtedly the most unbelievable re-entry ever survived. The PAO service module of the Soyuz failed to separate after retrofire. While this had occurred on various Vostok and Voskhod flights, and on one Mercury flight, it was a much more serious problem for Volynov, where the module was much larger than a small retropack. Furthermore, once it started reaching the tendrils of the atmosphere, the combined spacecraft sought the most aerodynamically stable position - nose forward, with the heavy descent module with its light metal entry hatch at the front, the less dense service module with its flared base to the back. Volynov at once appraised the situation and considered all possibilities and realised that there was nothing he could really do.
The spacecraft was re-entering air-lock forward and with every minute the G forces increased. Volynov did his duty with all of his strength but this became increasingly difficult since he was hanging in the straps of his seat with the G forces assailing him in the opposite direction from what planned. Soon a strong smell penetrated the cabin - the rubber gaskets of the hermetic seal of the hatch were burning. The hatch had a light covering of heat protective resins, but at the last moment these could not hold out and the vaporised into fumes that immediately spread throughout the cabin. Volynov could remain conscious for only a few seconds after this.
He remained alive when a miracle occurred - a miracle for which he could thank the designers who had included a strong titanium frame which helped the airlock hold out against the onslaught of the superheated plasma. The PAO service module finally separated from the SA re-entry vehicle. The capsule turned around to an aerodynamically stable position at hypersonic speed and the heat shield finally took the brunt of the heating as designed. The spacecraft continued on a 9 G ballistic trajectory. The damage to the capsule resulted in a failure of the soft-landing rockets. The landing was harder than usual and Volynov broke his teeth. The capsule was recovered 2 km SW of Kustani, far short of its aim point, on January 18, 1969 at 07:58 GMT. It would be seven years until Volynov flew again, on Soyuz 21.