Salyut 6
Expedition 1

Launch from the Baikonur Cosmodrome; landing with Soyuz 27 spacecraft 310 km west of Tselinograd.

Following a one day solo flight Soyuz 26 docked with the space station Salyut 6 on December 11, 1977. The staying time there was 95 days. An SEVA by Yuri Romanenko and Georgi Grechko occured on December 19, 1977 (1h 28m), inspecting the Salyut 6 docking port. The inspection confirmed that the Soyuz 25 spacecraft docking unit was at fault in its failure to hard dock, and that its docking attempts had left the Salyut 6 front port undamaged. It was later revealed that a potentially dangerous incident occurred during the EVA. Once Georgi Grechko was back in the airlock, Yuri Romanenko asked to look outside, so Georgi Grechko moved aside and Yuri Romanenko pushed hard against the airlock. He did not have his safety tether attached and began to float away from the station and thrash about. Georgi Grechko grabbed his commander by his untethered safety line and pulled him back in.

Numerous experiments were carried out over the next few weeks. Since this was an attempt to set a new space-endurance record, much of the focus of the mission was on medical experimentation. But other research was also done. Earth observations were made December 21, 1977 of the Soviet Union and of forest fires in Africa, and a new navigation system was tested on December 25, 1977. By January 03, 1978, the crew requested more work as they were nearly finished setting up the station.

The station required refueling by mid-January 1978, and this was to be accomplished by a new unmanned supply tanker, Progress. But the tanker had to dock at the aft port where the propellant line connections were, and Soyuz 26 was docked there. Mission control was not yet willing to attempt to redock the Soyuz at the other port, a now-standard practice. Accordingly, a new crew was sent up on another Soyuz spacecraft to dock at the forward port, and depart in the parked Soyuz 26 spacecraft.

Visits from Soyuz 27 on January 10, 1978 and from Soyuz 28 since March 02, 1978 arrived at the station. Common scientific work and experiments were performed.

The visiting crew brought supplies such as food, books and letters, equipment and a French biological experiment, and Vladimir Dzhanibekov, an electronics expert, inspected the station's electrical system. On January 13, 1978 the crews performed for the first time the now-routine exchange of seat liners and centering weights in their respective Soyuz craft. The liners are custom molded for each space traveler, and are needed for launch and landing, and the weights are needed to ensure a proper center of mass for the returning craft so it does not undershoot or overshoot the landing target. While the main reason for the Soyuz swap was to free the aft port for the Progress, another reason was that extended exposure to space of the vehicle leads to degradation of its engine and propellant seals.
A now-standard experiment called "Resonance" was carried out, which tested the stresses of the multi-spacecraft structure by simply having the cosmonauts jump up and down.

The Soyuz 28 crew left in the craft they arrived in, and returned to Earth March 10, 1978. No exchange of craft was contemplated as the resident crew were due to return soon themselves. During the visit, one of the Soyuz 28 crew informed Yuri Romanenko that Georgi Grechko's father had died. It was left to his judgment whether he should inform him during the mission or after they landed. He decided to wait for the completion of the mission.

By the end of the mission, Yuri Romanenko had developed an excruciating toothache, but there was little to stop the pain with on the station. All doctors at mission control could suggest was that he wash his mouth with warm water and keep warm. By the end of the mission—only six days after the Soyuz 28 crew's landing—a nerve had been exposed.

It was the first mission to receive visiting crews launched aboard another spacecraft, and to be resupplied by a logistics spacecraft (Progress 1) on January 20, 1978, delivering food, water, air and fuel. The crew also set a new flight duration record.