On Monday, as Tropical Storm Harold passed a bit to the north of Boca Chica, SpaceX continued work on Starbase upgrades, moving Booster 9 to the launch pad on Tuesday (video should start almost 10 minutes into a 16 minute video - 9:53 in, but it's not critical) and then lifting it off the SPMT (Self-Propelled Motorized Transport) (I think) and onto the OLM (Orbital Launch Mount).
It didn't take long for them to set up for a spin prime test on Wednesday,
which apparently went flawlessly.
They apparently took Thursday to go over the results and verify they were ready to do a second static firing of B9, presumably to make sure it doesn't have the same errors as the static firing earlier in the month that had four engines shut down early and the entire vehicle shut down at 2.74 seconds instead of burning the entire planned five seconds.
This morning, I was emailed a notice by NASASpaceflight saying SpaceX was planning a static firing today, and started their feed in a browser tab a little after 11:00 AM ET. The static firing was at 1:35 PM ET.
Screen capture from SpaceX coverage of the test.
Full video of the test is here, starting at 7:53 in the video and T-30 seconds. A shorter video with more views is from NASASpaceflight here. Within the first few minutes after the test, Elon Musk tweeted that it was a successful test and the NASA Spaceflight coverage said it appeared that the test was full duration. Late in the day, SpaceX confirmed that, tweeting:
Super Heavy Booster 9 static fire successfully lit all 33 Raptor engines, with all but two running for the full duration. Congratulations to the SpaceX team on this exciting milestone!
When you watch the coverage, you'll see a small water jet start to run at about T-20 seconds and the big deluge system starts up at about T-5 seconds. The engines start to light at T-2 seconds and then it's hard to see.
Before the live coverage on NASASpaceflight ended, the chopsticks moved from above B9 over to the side and down to the position that another SPMT might come to - presumably to lift S25 and stack it on top of the booster.
So what's next? Elon has said that he wants to launch "soon", perhaps in a couple of weeks. There's a Notice to Mariners [pdf] for "approximately September 8" citing "rocket launching activities," but we can't jump to the conclusion it's the launch date. The FAA has to complete its review of the Mishap Investigation Report that SpaceX submitted last week. Considering the pace at which fed.gov agencies work, as opposed to the pace SpaceX operates, the FAA might have read the table of contents. Then add in that the DOJ has sued SpaceX over not hiring enough undocumented immigrants and asylum seekers; we just don't know if that will slow things or not.
Obama's DOJ tried suing SpaceX because they wouldn't hire foreign nationals at the same time the DOJ was investigating SpaceX for possible ITAR violations.
ReplyDeleteSo this is just a rehash of previous actions.
Does this surprise you?
Cool on SpaceX for passing the firing test. Looks like the launch is in the FedGov's hands now. Which isn't promising.
I really don't understand what they've done wrong. I thought that's how ITAR/EAR worked.
DeleteElon has offended the Democrats by taking away X/Twitter from their control. He also has not paid baksheesh to the appropriate parties with a reserve 10% for The Big Guy. It is harassment pure and simple.
DeleteApparently the DoJ did this to Lockheed-Martin some years ago; the DoD had a talk with the DoJ and it went away.
Considering how much Artemis depends on Starship, maybe instead of DoD it'll be NASA? What if both NASA and DoD ganged up on them?
DeleteRight now SpaceX is the only reliable and 100% USA only flight provider, so the DoD is stuck using their services for, at least, until 2025, as even if Vulcan flies early in 2024, DoD requires a series of proven flights before they'll allow their missions to fly.
DeleteWell, hire a few migrants and put them in the rocket for the trip. Problem solved.
ReplyDeleteFar better to do that with Congresscritters and members of the Administration!
DeleteEven Starship doesn't have enough room to dot that. We'd have to wait until we have a fleet of Starships.
DeleteThen we could reenact that scene from Hitchhiker's Guide to the Galaxy where all the politicians and managers were told the planet had to be evacuated because of impending doom and all of them were given priority seats. "We'll catch up with you some day," which got all the useless corrupt people off the planet.
I'm pretty sure it was Hitchhiker's Guide.
Yes, SiG, you are correct. Telephone Sanitizers et al !
DeleteAnd then everyone died of a plague from a virus that mutated on telephones.
DeleteI would pay good money for a proper technical report detailing precisely why these engines aren't starting up. Apparently they don't have this problem on the test stands at MacGregor, so it's an issue with fuel supply or sympathetic vibrations or sequence or firex or valves or...?
ReplyDeleteMe and you both. When I read that Super Heavy Booster 9 static fire successfully lit all 33 Raptor engines, with all but two running for the full duration. I was grinning all the way up to "...all but two..."
DeleteI understand "proprietary knowledge" and all, but this has been going on too long. Turn on all 33 and have them all run for the full two or three minutes the booster has to run. The only way that can be tested is at Stennis or in flight.
If I had to make a guess, I'd look very closely at fuel/oxidizer delivery. The manifolding is complex, and may harbor pathological turbulence somewhere, possibly triggered by vibration. I would be running the hell out of the fluid dynamic simulations of the design.
DeleteAnd they probably are.
SiG, if they were to run them for two or three minutes, there were probably be damage to the OLM. I think SpaceX has tried to make the OLM just robust enough to last the few seconds that the Superheavy is close to it.
DeleteI agree with Malatrope that there is probably something unusual going on in the fuel delivery system that causes the engines to shut down prematurely. I am guessing that it is the outer ring of engines where the problem is. I commented over at "Behind the Black", that they will probably be chasing these issues and have one or more static fires until it is solved. Plus, they may need to go back and do some fixes "under the hood" to alleviate problems.
It would be interesting to see if the problem went away after the vehicle experiences some acceleration. Unfortunately, the only way to test that is to launch the thing and try to restart the engines that shut down.
ReplyDeleteIt is also possible that the software limits are too sensitive to some changes, and just allowing a bigger range would solve it. Without blowing them up, of course. As my signature over at NSF says, "Space is hard. Hard is fun."
It makes me modify the old aphorism, "when you look at things no one has ever looked at before, you see things no one has seen before." In this case, change the first statement to "when you work on things no one has worked on before..."
ReplyDeleteModeling only gets you so far. Testing the entire 33 engines and hardware at someplace like Stennis gets you much closer, but anything fixed there still needs to fly.
Forget Stennis, you have to fly. Too many things are different when the thing is actually flying, like vibrations, flex, acoustics, g-forces. Heck, Goddard knew that much (and discovered it in spades). For all we know, the vibrations from the engines against the manifold is creating cavitation bubbles. Remember, the vibration spectra will be different with different mountings and masses. Gotta use the ship.
ReplyDeleteI see a couple more static fires on the calendar, whether they admit it or not.
Heh. Cavitation bubbles. That's what doomed early F1s until they installed baffling at the ejectors.
DeleteWell, it would be interesting to see their design up close and personal. One assumes they've studied the old masters, but SpaceX can sometimes be extraordinarily clueless about the little things.
Delete