Digital Soyuz Return Could Be Rocky

First mission has some kinks to work out

4 min read

14 March 2011—The new ”digital” version of the Soyuz spacecraft is having some decidedly analog problems on its maiden voyage. Astronauts will test on-orbit repairs made to its troubled control systems ahead of a scheduled landing on Wednesday, 16 March. The tests will determine whether the Soyuz can perform a gentle guided descent or if it must rely on a backup emergency ”ballistic” landing instead, which would involve a much rougher deceleration and require the team to land several hundred kilometers short of the main recovery zone.

The digital Soyuz differs from its predecessors in that it has a computer upgrade, and the five incompatible analog processors for monitoring different spacecraft systems have been replaced with a single digital device called MBITS (the Russian acronym for ”small-sized onboard informational telemetry system”). MBITS promises to make transmission of spacecraft parameters much more efficient, so that Russia can meet the rapid launch demands needed to keep the International Space Station (ISS) crew at six in the absence of the U.S. space shuttle fleet.

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Two men fix metal rods to a gold-foiled satellite component in a warehouse/clean room environment

Technicians at Northrop Grumman Aerospace Systems facilities in Redondo Beach, Calif., work on a mockup of the JWST spacecraft bus—home of the observatory’s power, flight, data, and communications systems.


For a deep dive into the engineering behind the James Webb Space Telescope, see our collection of posts here.

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