Space Launch System Delayed Again With Short Test Fire

The test-fire of the Space Launch system rocket two days ago should have lasted eight minutes but the engines shutdown after one minute. Eight minutes is the time to launch the rocket to orbit. A one-minute firing on an actual launch would have meant a failure to reach orbit.

The Space Launch System collected data but even if they find a simple problem, it would be reckless to proceed to an actual launch without a good test.

The Space Launch System needs months to prepare for a full test firing.

NASA has 16 RS-25 engines which were salvaged from the old space shuttle program. Those engines will be used on the first four SLS rocket launches for Artemis missions 1 through 4. Clearly, NASA has been wasting money trying to use the old engines. They have spent about $30-40 billion and over twenty to get to this failed test. This includes the SLS program and the constellation program.

The two main champions of the SLS are no longer in the Senate.

This continued failure will likely cost the SLS program the Europa Clipper launch. There are problems making the SLS compatible with the Europa Clipper.

If SpaceX can complete a successful flight to orbit with the Super Heavy Starship in 2021, then the SLS program could finally be killed. The Super Heavy Starship would have more payload capacity and would be over ten times cheaper than SLS.

Written by Brian Wang,

56 thoughts on “Space Launch System Delayed Again With Short Test Fire”

  1. SLS was never meant to be productive. It's simple congressional graft for the military industrial complex while the U.S. lulls in its aggression.

  2. "You mean private space companies like Boeing"

    Boeing a private space company? <laughs derisively in human>

  3. The exhaust from the original design was found to contain dihydrogen monoxide.

    Or as a principal chemist said when I mentioned that famous pollutant "Oh, do you mean protonated hydroxide?"

  4. You mean private space companies like Boeing, Orbital ATK, Aerojet Rocketdyne & Lockheed Martin? I think any entity with funding can employ engineers, always cheaper than paying retail for work product from 3rd parties.

  5. Not to argue, but on the other hand, both Shuttle and SLS use SRBs, so the "first" stage is a little vague compared to Musk big booster. SLS *core* is like a combo of External Tank and SSMEs, so like stage 1.5 or something. I still find it confusing, in that there is not a clear principle to cite, rather all sorts of trades off. And that is without Carbon fiber v stainless structure!

  6. H for a first stage is not ideal. H as a fuel is high ISP but lower thrust at the point where thrust matters most (liftoff).

    SLS went with H first stage engines because that is what NASA had at the time. Remember that SLS is based on currently existing parts because that was the way to reliably get back to orbit as quickly as possible.


  7. Thanx! I would point out that LCROSS found quite a lot of C too, but H fuel will be everywhere on Moon, rockets and electricity. Probably harder to make CH4, but I HOPE Musk decides to do it anyway instead of Earth launching fuel. If he brings raw polar rego to Halo Industrial Park, everybody can play with it. edit: The suite of LCROSS and LRO instruments determined as much as 20 percent
    of the material kicked up by the LCROSS impact was volatiles, including
    methane, ammonia, hydrogen gas, carbon dioxide and carbon monoxide. The
    instruments also discovered relatively large amounts of light metals
    such as sodium, mercury and possibly even silver.

  8. Musk's reasoning isn't that confusing. Methane isn't as hot a fuel as hydrogen, but it's good enough, and a lot easier to handle. And hydrogen is a lot more expensive than methane.

    As Musk drives down the cost of the actual rocket hardware, the cost of the fuel becomes a significant consideration.

    For upper stages the actual amount of fuel being used is considerably less, and spending money to have less weight of fuel there reduces the size of the required 1st stage a lot. So the economic considerations work out differently. 

    Hydrogen doesn't gain you as much as you'd think, due to being deep cryogenic and very low density. (Between 6 and 7 times less dense than methane!) Both those factors push tankage weight up, erasing a lot of the ISP gain. Musk figured it just wasn't worth the hassle, and economized on engineering investment by sticking with methane for all stages.

    The calculus is different for Bezos, because he's aiming for a Moon based launch system eventually, and the Moon is notoriously carbon deficient. Hydrogen would make sense for him even if it didn't have a higher ISP.

  9. Of course, they would get modern specs with the new engine, but I do remember you not liking H where not absolutely needed. For boosters, the advantages of H can be replaced with a larger tank of gas, without changing anything riding on top. If the second stage is not H, however, then the booster also has to be bigger. Musk does this, too. Almost as confusing as rocket science.

  10. I suppose you could ask Blue Origin, since they've developed an engine with a third of the thrust recently. I don't doubt that they could develop a RS-25 replacement to modern specs for less than the cost NASA has already contracted to pay.

    I question the logic of a hydrogen burning first stage anyway. The fuel density being so low is a real problem.

  11. There will be a hold up because they will have to start over when designing engines to use enviro-mental-ly safe fuel and oxidizer that smell like lavender when lit.

  12. Of course, that is SLS, not ULA overall. BO is in charge of Halo Industrial Park refueling effort. Orbital. O'Neill. Practical. $$$$

  13. I think you are implying that a socialist space program would have excelled at innovation. If only there was some private space company that we could compare SLS to. We could come up with metrics like money spent, launch success rates, reusability, etc.

    I mean the hypotheticals are amazing!

  14. If SLS is a problem, it's all your fault.

    All thanks to your generation's fetishization of the private sector and the pseudo religious belief that governments exists to feed money to private sector. They cannot engage in activities that could compete with the best interests of the private sector.


    The pork must flow…to private sector businesses in certain districts.

  15. So, how much would a new design big H engine be? From what you say, we essentially do not have one, that can be afforded. Do we need one, if gas works for boosters?

  16. He probably learned his lesson in the end. Or rather about 5 seconds before the end. Way too late to implement his new wisdom.

  17. Agreed. That dude who got eaten by grizzly bears after claiming he figured how to live with them is also an example of a something not being learned. >_>

  18. They have already issued a contract to manufacture 18 new engines for a total contract price of $1.8bn or $100m per engine. However they’ve already been given a contract for restarting production and 6 engines, so in total they’re receiving $3.5bn for 24 engines, or $145m per engine. By comparison, Musk says each Raptor costs $1m. Like the RS25, also designed to be reusable, and with a similar level of efficiency. Crazy.

  19. The RS-25 is a great performing engine, high performance H2/LOX. Maybe not the way we'd design one today, but an impressive engine for the time.

    It's also designed to be reusable, so naturally NASA is using it in a throw away application.

    It's almost as though the SLS was designed for the specific purpose of wasting museum pieces. (They have 6 available.)

    Well, they HAVE let a contract to manufacture 18 additional engines. At a mind boggling $100M each!

    Apparently they only expect to ever launch the SLS 6 times in total, since each flight consumes 4 engines.

  20. When Starship reaches orbit, logic would demand that NASA partner with SpaceX and drop the SLS. We'll see if logic prevails — not hopeful.

  21. After two years the blue ribbon committee will come to the conclusion that they need to make new engines.

  22. Once NASA switches to Rusike engines they will form a blue ribbon committee to evaluate their options.

  23. This is an old style contract, design not really under contractor control. New style *purchase service* rather than *build this* far better. But you have to be doing something that makes $$$ eventually for it to work well. Then, the gov customer is more of an official protective presence than the only goal.

  24. If you think that NASA spent 20 Billion dollars on this rocket you are not paying attention. NASA is just using the SLS launch system as a great big allocation bucket.

    "Hey, we are all getting new laptops. Charge it off to the SLS bucket."

    "Oh boy, we are going to Vegas for a week of training. Charge it off to the SLS bucket."

    "Let's enact a new Inclusivity Department. Allocate their cost to the SLS bucket."

  25. Nasa not even tested the gimbaling (after 2 min).
    They defininatly NEED a new >2min running test.

    Still I prefer others that with just 50% change of success go for it, and mention that it might fail. "Underpromise and over deliver."

  26. It's been reported that Launch Alliance management told engineers to keep their mouths shut about orbital refueling, since that would require fewer launches overall.

  27. SLS lost my indifference when I learned they had actively suppressed talk of refueling. That is going too far in stopping progress. Almost as bad as letting Mars people suppress lunar rovers and such.

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