Main Engine Cut Off

Perhaps, the most important change pertains to the ship’s famous automated rendezvous system known as Kurs (“course”), which has guided Soyuz to its destinations in space since the mid-1980s. Though the Kurs proved exceedingly reliable over the years, many of its electronic components are now out of date. They’re also produced in Kiev, Ukraine, with whom Russia has been at a virtual state of war for two and a half years. Not surprisingly, Soyuz-MS will introduce the domestically developed Kurs-NA system. In addition to resolving the obvious political problem, the new rendezvous hardware brings a higher level of computerization while being smaller, lighter, and less power-hungry.

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The large antenna array of the EKTS system “on the roof” of the Soyuz-MS is the most prominent new feature on the ship’s exterior. Thanks to three available Russian Luch-5 satellites, the crew will be able to stay in touch with mission control around 83 percent of the time each day. The Soyuz will be also able to communicate via American TDRS and European DRS satellites.