On April 29, 2016, Roskosmos announced that the launch of Soyuz MS-01 had been postponed from June 21 to June 24. The launch campaign for the mission began in Baikonur in January 2016 with autonomous tests of the Soyuz FG launch vehicle inside a processing building at Site 112. The work started earlier than scheduled to free room for another rocket, which was slated to launch Soyuz TMA-20M in March 2016.

From May 20 to May 25, Soyuz MS went through vacuum chamber tests.

At the beginning of June 2016, technical problems with the flight control system forced to delay the mission again, this time until July 7. A glitch in a flight control unit known as BURK (one of the new features on the MS series), reportedly required to return the system back to Moscow for re-installation of its software.

During a visit to Baikonur on June 25, the prime and backup crews underwent the final dress rehearsal of suiting-up operations for the flight and pressure checks on their spacesuits. They also had a familiarization training inside the actual spacecraft, which was undergoing its final processing at Site 254. The crew members tried communications systems and a laser range finder and had a final look at onboard documentation, including their cargo list.

Critical irreversible operations began with Soyuz MS on June 28, with the fueling of the spacecraft and loading of the pressurized gases. On the same day, the spacecraft was attached to its launch vehicle adapter.

On June 30, 2016, RKK Energia officials conducted the traditional final inspection of the fully assembled Soyuz MS inside the processing building at Site 254, before the spacecraft was hidden under a protective fairing of the Soyuz-FG launch vehicle.

Upon reaching its planned orbit, Soyuz MS-01 was 315.3 degrees away and below the ISS, which at the time was circling the planet in the 401.65 by 420.81-kilometer orbit.

To test all its new systems, Soyuz MS-01 followed a two-day, 34-orbit rendezvous scenario rather than a much faster six-hour flight profile practiced in recent missions. According to the Soyuz commander, Anatoly Ivanishin, the first test of the manual flight control system was to be conducted after entering orbit (while another such trial would be attempted after undocking from the station.)

ompleting a 115-day mission, Soyuz MS-01 undocked from the MIM1 module, the part of the Russian segment of the station at 8:35:00 p.m. EDT (03:35:00 Moscow Time on Oct. 30, 2016), marking the official beginning of Expedition 50 on the ISS. A command for undocking was issued a minute and a half before springs of the docking mechanism pushed the spacecraft away from the station.

After three minutes in solo flight, Soyuz MS-01 conducted the first of two small maneuvers with its attitude control thrusters to increase its distance from the ISS. The first firing was scheduled at 03:38:00 Moscow Time and the second should take place at 03:44:20 Moscow Time. Between the two maneuvers, Anatoly Ivanishin conducted several tests of the manual control with newly arranged DPO thrusters on the Soyuz MS vehicle.

After two days, Soyuz MS-01 arrived underneath the ISS and navigated toward the nadir port of the Rassvet module ahead of a successful docking.

Assuming a proper mission, Soyuz MS-01 will remain docked to the Station until at least November 2016 for a roughly four month stay at the orbiting laboratory.

For the duration of its mission, Soyuz MS-01 will carry a call sign of Irkut – a river in the Buryat Republic and Irkutsk Oblast of Russia, which contains the hometown of Soyuz MS-01 Commander Anatoli Alekseyevich Ivanishin.

The MS variant is the last in a series of planned upgrades for the veteran Soyuz vehicle of the Russian Federal Space Agency (Roscosmos).

The new MS series sports more efficient solar panels, a new Kurs NA approach and docking system weighing less than half that of its predecessor, additional micro-meteoroid debris shielding, and a modified docking and attitude control engine – which will add redundancy during docking and deorbit burns.

Moreover, its main computer, a TsVM-101, weighs one-eighth that of its predecessor (8.3 kg vs. 70 kg) while also being much smaller than the previous Argon-16 computer.

This new MS-series Soyuz also uses a unified digital command/telemetry system that allows telemetry to be relayed via satellite for control of the spacecraft as well as to provide crew with positioning data when the spacecraft is out of range of ground tracking stations.

Furthermore, the GLONASS/GPS and Cospas-Sarsat satellite systems have also undergone major upgrades to provide more accurate location services during search/rescue operations after landing.

To this end, only minor changes for the MS Soyuz series based on flight data/behavior are planned before the entire Soyuz vehicle family is retired.

While no date (not even a notional one) has been set for that retirement, it is currently understood that the Soyuz vehicles will be replaced by the Federation vehicle – a multi-person, partially reusable piloted spacecraft envisioned by Roscosmos to allow for the continuation of Low Earth Orbit transportation as well as lunar missions.