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.

Tested spacecraft systems and designs, manoeuvring of space craft with respect to each other in orbit, conducted scientific, technical and medico-biological experiments in group flight. Was to have docked with Soyuz 8 and transferred crew while Soyuz 6 took film from nearby. However failure of rendezvous electronics in all three craft due to a new helium pressurization integrity test prior to the mission did not permit successful rendezvous and dockings. Recovered October 17, 1969 9:26 GMT.

Manned flight endurance test. Medico-biological, scientific and technical studies and experiments in prolonged orbital flight. Inconclusive results due to slow sun-oriented rotation of spacecraft to conserve fuel producing motion sickness in cosmonauts. Recovered June 19, 1970 11:59 GMT.

By December 1970, there were four crews in training for two pairs of Soyuz spacecraft to be launched to test the Kontakt lunar rendezvous/docking system. The launches at that time were scheduled to occur after the missions to the Salyut 1 space station were completed. Soyuz Kontakt 1 would have been the active spacecraft of the first mission.

Final crews selected for a dual Soyuz mission in Earth orbit to test the Kontakt docking system to be used on the lunar landing LOK and LK spacecraft. The Kontakt-A Soyuz would have been the active spacecraft, simulating the LOK lunar orbiter.

ASTP Manned Test Flight. Check-out of the Soyuz space craft's on-board systems which had been modernized to meet the requirements of the 1975 joint flight in accordance with the programme of the Soviet-United States experiment; conduct of scientific and technical investigations. Landed 30 km NE Arkalyk. Recovered December 8, 1974 8:04 GMT.

Soyuz 19 initial orbital parameters were 220.8 by 185.07 kilometres, at the desired inclination of 51.80°, while the period of the first orbit was 88.6 minutes. On 17 July the two spacecraft docked. The crew members rotated between the two spacecraft and conducted various mainly ceremonial activities. Leonov was on the American side for 5 hours, 43 minutes, while Kubasov spent 4:57 in the command and docking modules.

After being docked for nearly 44 hours, Apollo and Soyuz parted for the first time and were station-keeping at a range of 50 meters. The Apollo crew placed its craft between Soyuz and the sun so that the diameter of the service module formed a disk which blocked out the sun. After this experiment Apollo moved towards Soyuz for the second docking.

Three hours later Apollo and Soyuz undocked for the second and final time. The spacecraft moved to a 40 m station-keeping distance so that an ultraviolet absorption experiment could be performed. With all the joint flight activities completed, the ships went on their separate ways. Soyuz 19 landed safely July 21, 1975 10:51 GMT, 87 km north-east of Arkalyk, 9. 6 km from its aim point.