Soyuz rocket launch scrubbed due to faulty IMU

Uh-oh: A Soyuz rocket launch from French Guiana was scrubbed an hour before launch on Sunday because of detected problems with the inertial measurement unit (IMU) in its navigational system.

Arianespace chief executive Stephane Israel tweeted Sunday that the faulty inertial measurement unit, or IMU, will be replaced overnight in time for a launch attempt Monday. The IMU is located on the Soyuz rocket’s third stage and is used to determine the heading and orientation of the vehicle in the first nine minutes of its mission, feeding critical attitude data to the launcher’s guidance computers, which transmit steering commands to the engines.

The venerable Soyuz booster flies more often than any other launcher in the world, and delays due to technical causes are rare. [emphasis mine]

This is not good news for Russia’s aerospace industry, as it suggests that the quality control problems Russia has experienced with the company that manufactures its Proton rocket are now beginning to appear with the different company that manufactures the Soyuz rocket.

If true, this is also very bad news for American astronauts, who must use this rocket to get to and from space.