The crew consisted of Yuri Romanenko and Georgy Grechko. Their call sign for the mission was Taymyr, after the Russian peninsula. The crew were launched aboard Soyuz 26, and are often referred to as the Soyuz 26 crew, even though they returned to earth aboard Soyuz 27, a few months after the Soyuz 26 spacecraft had been landed.

On 20 December 1977, the crew performed the only spacewalk of the EO-1 mission. The purpose was to inspect the forward docking port to assess whether there was damage which might have prevented Soyuz 25 from docking two months earlier. The spacewalk was the first one by the Soviets since cosmonauts from Soyuz 5 transferred to Soyuz 4 in 1969. The spacewalk was also significant as it was the first use of the Orlan space suits (which are still used today on the International Space Station).

The issue of whether the front docking port was broken, and if so was salvageable, was crucial to mission planners. If there was only a single usable port, only short-duration missions were possible at the station. The Soyuz 25 docking apparatus burned up during re-entry in October, so it could not be determined whether the fault lay there.

Grechko left the Salyut while Romanenko remained in the depressurized airlock. He reported that there was no visible damage to the docking drogue, which meant that the docking mechanism on Soyuz 25 was faulty, not that of Salyut 6. Accordingly, the station’s program was rescued. Additionally, he placed a materials exposure experiment on the exterior of the space station to be retrieved by a subsequent crew. The EVA lasted 1 hour and 28 minutes.

It was later revealed that a potentially dangerous incident occurred during the EVA. Once Grechko was back in the airlock, Romanenko asked to look outside, so Grechko moved aside and 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. Grechko grabbed his commander by his untethered safety line and pulled him back in.[2] (In an interview afterward, he reported he asked Romanenko, “Yuri, where are you going?”) Grechko felt the incident was overblown by author James Oberg to sound more dangerous than it really was. Although Romanenko’s safety tether was not attached, there was still the electricity/communications umbilical that would have held him to the station. Another complication occurred when the gauges indicated no air was refilling the airlock. However, it was soon realized the gauges had to be faulty, and they safely reentered the station.

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 21 December 1977 of the Soviet Union and of forest fires in Africa, and a new navigation system was tested on 25 December 1977. By 3 January 1978, the crew requested more work as they were nearly finished setting up the station.

Here is that report from the English service of Radio Moscow, as it was broadcast on December 21, 1977.

December 21, 1977 – Radio Moscow (English Service) – News reports on progress of Salyut 6 and Soyuz 26 – Gordon Skene Sound Collection.

December 21 1977 – while Earth continued its inevitable spin, the news above Earth was grabbing headlines. Salyut 6 EO-1 was a Soviet long duration space expedition, the first to dock successfully with the space station Salyut 6. The two person crew stayed were in space for a record setting 96 days, from December 1977 to March 1978. The expedition was the start of what would be the semi-permanent occupation of space by the Soviets.

The expedition set several records and established several milestones, including the longest space flight to that time, the first docking of three spacecraft together, and the hosting of the first non-Soviet, non-American space-farer. Additionally, the mission saw the first spacewalk by the Soviets since 1969. An important modification from previous Salyut stations which made many of these feats possible was an extra docking port on Salyut 6, which allowed for re-supply missions, visiting crews and, potentially, crew rotations and permanent occupation.