Saturday, January 16, 2021

SLS Green Run Engine Test Aborts After 67 Seconds

The SLS Green Run test of the core stage at Stennis Space Flight center aborted after about 67 seconds today.  The intended test was to be 8 minutes but somewhere just a few seconds short of the shutdown, the video narrators said they heard something like "MCF" - Major Component Failure - and soon thereafter the engines shutdown. 

Video capture about 30 seconds into the test. 

The commentators on the video say that before the test, someone (Boeing rep.?) had said they'd get just about everything they needed with a minute and a half test, so they came up short of that.  Not to put too much of a smiley face on the situation, but the test is also supposed to test things like the way the software would handle a contingency, and that apparently worked properly.  Everything seemed to shut down in a controlled way.  Nothing was apparently destroyed - the core stage is still in the test stand after the shutdown. 

Unfortunately, being a weekend, we're not likely to see anything official out of the SLS program discussing this for at least a couple of days while they analyze their data and try to understand why the system shutdown. 


  1. I heard that something failed but not much more. Thank you for the update.

  2. Just goes to show, space is hard.

    Still much more impressive than Blue Origins...

  3. If only there was a company making reliable engines . . .

    1. Certain other companies with methane/lox engines seem to be having issues making lots of them that work reliably, too.

      Design For Manufacturing. It's not just a good buzzword.

    2. At least that one company making methane/lox engines is actually testing working models and trying to make them work... And so far, three have safely gotten above 10 kilometers. Kinda messed up after a non-engine failure during landing, but still, so far above B.O.

    3. The thing that keeps getting me is they're going to put 28 Raptors in the Heavy booster and getting three that work together and (I assume) match performance seems to be an issue. They seem to swap them out very routinely. Getting 28 to match seems a long way off.

      My more mature side says these are just signs of an immature design. I want to see them make it routine but it isn't, yet.

      OTOH, SLS is using Space Shuttle Main Engines, and has like 16 engines Shuttle program gave them. These are the most flight-proven engines in the world, and one of them apparently had a "major component failure" during the static fire test.

      Rocket engines are hard to get right.