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Friday, November 17, 2023

The Reason Flight Test 2 is so Important

Whether Starship IFT-2 flies on Saturday morning or is held another few days or a week isn't really important.  What's important is that it needs to be a successful test.  The booster needs to burn for the full required time, the hot-staging needs to work, Starship needs to achieve its intended trajectory and it needs to splash down in the Pacific as intended.  

Why?  Simply that for the HLS or Human Landing System version of Starship to work is going to take nearly 20 successful missions and that says launches have to be routine.  

In a presentation at a meeting of the NASA Advisory Council’s human exploration and operations committee Nov. 17, Lakiesha Hawkins, assistant deputy associate administrator in NASA’s Moon to Mars Program Office, said the company will have to perform Starship launches from both its current pad in Texas and one it is constructing at the Kennedy Space Center in order send a lander to the moon for Artemis 3.

SpaceX’s concept of operations for the Starship lunar lander it is developing for the Human Landing System (HLS) program requires multiple launches of the Starship/Super Heavy system. One launch will place a propellant depot into orbit, followed by multiple other launches of tanker versions of Starship, transferring methane and liquid oxygen propellants into the depot. That will be followed by the lander version of Starship, which will rendezvous with the depot and fill its tanks before going to the moon.

Much like Starship itself, there are simulations of what it takes to do the sort of operation this entails but - here's the key point - it has never been done before by anyone.  SpaceX has shown Concept Of Operations documents for the Human Landing System (HLS) program that talk about multiple launches of the Starship/Super Heavy system. One launch will place a propellant depot into orbit.  There have been reports or speculation that was the purpose for Ship 26 which had no thermal tiles or "flings" (control surfaces) - they're not needed if doesn't come back down - but S26 now appears to be obsoleted and in the "rocket garden" at Boca Chica.  Whatever that propellant depot looks like, the launch will require multiple other launches of tanker versions of Starship which transfer methane and liquid oxygen propellants into the depot. That will be followed by the HLS version of Starship, which will rendezvous with the depot and fill its tanks before going to the moon.

Again, while a large number of people can cite concerns about things like fuel evaporation and leakage on orbit, nobody has hard test data they're dropping on NASA.  

Exactly how many launches will be required has been a point of debate since Starship’s selection by NASA for the first HLS award in 2021. Neither NASA nor SpaceX have given firm numbers recently. A paper about the HLS program presented at the 2023 International Astronautical Congress by NASA, for example, mentioned only “a series of reusable tanker Starship variants” that would be launched to fill the depot before the Starship lander is launched, without giving a number.

Assistant deputy associate administrator Hawkins has said, “It’s in the high teens in the number of launches.  In order to be able to meet the schedule that is required, as well as managing boiloff and so forth of the fuel, there’s going to need to be a rapid succession of launches of fuel.” 

For additional perspective, the Government Accountability Office, in its rejection of protests by Blue Origin and Dynetics of the Starship HLS award in 2021, noted that SpaceX required 16 launches overall for a Starship lunar lander mission.  Elon Musk disagreed, calling the need for 16 launches “extremely unlikely” in an August 2021 Twitter (before it was X) post. He said a “max of 8” tanker launches should be needed to fuel the Starship lander, adding it could be as few as four.  

Between four and 20 launches?  They'd better be more like Falcon 9's cadence of one every three days than the seven months between the first flight test and this one.  Seven months delay times 20 launches isn't a nice number.  One month between each of 20 launches isn't that nice, either.

Illustration from the NASA presentation at the 2023 International Astronautical Congress linked above.



12 comments:

  1. 7 months between launches is NOT a technology problem, but a Gubmint problem.

    Get the hell outta the way, FedGov. Tell the Enviroweenies to stand down and shut up!!

    It's doable.

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    1. Not under THIS Administration! Nor with our current "Legal" system.

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    2. It is nothing but a Gubmint problem. And they're all environweenies, not to mention watermelons.

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  2. That was remarkably clean and smooth all the way up until the Starship was lost. The 33 raptors lit and stayed on the whole way, hot staging worked, and yeah, the booster did a RUD, but at that point, it had done everything.

    I'm not sure, but I think the Starship got higher into space than the suborbital tourist flights.

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    1. I know they are instrumented up the wazoo, and I hope they tell us exactly why the FTS triggered (on both the booster and the ship, apparently). The booster appeared to be leaking profusely during the flip maneuver, and the ship was definitely having some engine problems. The pressures in the interstage are probably right off the top of the gauge during sep, might have damaged something.

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    2. It got to 148 Km (88 miles) at the last report on the SpaceX feed. The final reported velocity was 24,124 Kph.

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  3. That. Was. EPIC!
    'Twill be interesting to see the AAR on why both booster and ship terminated themselves. For only the second launch it was remarkably successful from an engineering perspective. This is all new stuff and the scrutiny from all Agencies that are involved will make a proctologist blush...

    Hey, let's do it again! And again!!

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  4. The FWS can't have too many objections as that was a clean launch compared to ITF-1. I saw some debris flying about but they look fairly light and didn't go far.

    It looks like another 6+ months before the next flight because the FAA will be having their (collective) nose up SpaceX's business for both stages failing even if SpaceX, the experts on the system, can come to quick conclusions on what happened and what corrective actions need to be taken.

    Expanding on what Malatrope said about the hot staging, I think that they will increase the height of the hot staging ring. I expected to see only the vacuum engines immediately after staging, but all 6 Starship engines were lit.

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    1. Existing hot-staging designs have a more open structure than this one. I am concerned that there is only ~50% of the area open to allow gases to escape in SpaceX's concept. I realize that this is likely because it uses the same rib-and-cylinder method as the other structure, but they may have to rethink this. I agree that it will, at the least, get taller.

      I would love to see the profiles on their telemetry. What condition was the pressurization on the top booster tank? How hot did the structure get? What was the pressure within the hot stage ring as it separated? Did they light all six engines at once, or only the vacs until there was separation?

      Of course, all the evil, rat fink media are running headlines like "Starship fails AGAIN", which makes me want to crush some skulls. Liars, all.

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    2. "If you dont read the press, you're uninformed; if you do read the press you're misinformed." ...someone famous once.

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    3. I seems to me (taps top of head) that due to the failure of the self-destruct on test 1, they might have wanted to prove to the powers that it would work this time. Just sayin'.

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  5. Well, after half a day to analyze the videos of the flight, it appears the booster suffered from some kind of leak, which triggered the AFTS, and then the Starship shut its engines down prematurely juuuuuust before SECO - cause unknown but maybe another leak as the O2 levels were dropping FAST towards the end of the Starship boost. Don't know if it was a command detonation or if the flight computer said, "screw it!"
    More's the pity, it was almost there!!

    All 33 +6 engines worked flawlessly!

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