Ultimate Steve

Hmm, I did a double take and thought it was an Electron for a second.

The Apollo capsule was also at 100 percent oxygen, 1/3 atmospheric pressure. As most capsules today are focused on transfers to and from long term LEO habitats, you're going to end up with a heavier structure and environmental control system for something that is sea level pressure nitrogen and oxygen. You also state that the service module would not be needed for LEO missions. While if they had done this a lot, they doubtless would have made a smaller service module, they would have certainly needed a service module to do anything more than a suborbital hop. That thing provides power generation, I think oxygen and water, propulsion, rcs to dock with, and a lot more. If you just wanted the clout of having sent people to space, sure, but such a spacecraft would be utterly incapable of doing anything more than that.

https://www.nasa.gov/foia/nasa-e-libraries/headquarters-foia-library/ WB-57 videos got released, but with the hot staging and flip removed, likely ITAR or trade secrets or something (smh). Looks like the heat shield teams have got a lot of work to do. I know they have heat shield upgrades already assembled on one of the upcoming ships, hopefully they figured it out this time. That is not a happy looking heat shield.

As far as a paying for college job goes, I am paid 20.79 an hour to sit in a comfy chair in an air conditioned structure, entrusted with a complicated mechanical machine, with consistent hours. The job is contractually required to schedule around my classes (I've had to exercise that right three times this month because my arranged classes kept changing, lol), and I can go from my dorm to punching in, with a ~10 minute bike ride. Much preferable to working in a dining hall or retail or grading papers or tutoring, for me at least. The only other thing I could ask for would be an easier time getting time off. The only caveat is that I don't really like driving, but given that no space company exists in a small town, driving with significant vehicular and pedestrian traffic is a skill I'll likely need, and I'm being paid to learn it! Right now, it is looking like I will graduate without debt, which is a massive win and a huge source of relief. The 100 grand price tag scared me so much going in, and now it has been chipped away scholarship by scholarship, grant by grant, and bus driving shift by bus driving shift into basically nothing. Now all I have to do is not fail any classes this semester (and, you know, get a job in this economy with a resume that could be significantly better).

Step AWAY from the bus. Your S needs to get to Mars. And not as a bus driver. Gotta pay for the degree somehow! Edit: Been doing this for a year and a half now, I intend to drop it the instant I get an actual space job. Today was just the first time I got to drive the bendy buses (and the electric ones too), I basically got "niche bus" trained today.

Are you sure that number in the figure is the mass and not the maximum mass of payload you can stick into it?

Been a while since I posted here. I got to drive one of these today:

I don't know if the telemetry is accurate, but it appears it tumbled upon landing.

It might be as simple as wanting to not carry 100 tons of liquid oxygen through re entry (ship may not be structurally capable of re entering with significant fuel outside the header tanks), and it may be easier to drain the lox while under acceleration. While they could do this with ullage or something it may not have enough time in its atmosphere crossing orbit to drain it all that way. Underfilling would not be done in case of a lot of engine outs or other underperformances. Also to keep dynamic environment similar.

Probably wanted margin in case of engine outs, and a similar acceleration and vibration environment to what would be on a normal flight. This kind of reminds me of the very first Centaur mission, where the boiloff vent for the propellants was not adequately separated from the main engines and led to an explosion.

Yeah that looks better. You can also do ctrl-shift-v to paste without formatting instead of ctrl-v and save a few clicks. That will also remove italics and such, though, and might break links, not sure.

This is Kerbal Space Program we are talking about here. If a player wants to be able to dock two kilometer long spaceships together, they should be able to do so. I often forget that myself with how deep I get into hyperoptimizations and low mass missions. Not everyone plays for realism or for things that would make sense from an engineering perspective. I do find it odd how we have a 60 ton RCS tank in the game right now but no RCS thrusters larger than default.

Floor 4451: Storage for the infinite amount of musical instruments needed to keep the infinite amount of mes sane.

Another thing I've thought up in another discussion. People often do a lot of Artemis to Apollo comparisons, and those not in the loop are often very confused by how goofy Starship looks next to Gateway. I think I've come up with some words that adequately sum up why. Apollo was a program defined by what was possible to make in a decade. Artemis is a program defined by what we have available right now, as the political will to build anything dedicated from scratch is very low. What we happen to have right now just so happens to be Beefy Apollo incapable of getting a lander to Low Lunar Orbit, low flight rate orange rocket incapable of doing much more than launching Beefy Apollo, promising medium and medium-heavy commercial rockets, minimal lander budget, and ambitious aspiring Mars colony builder that is also capable of landing on the Moon if rapid refueling works. Plus Blue Moon but I couldn't figure out a funny name for it. That is the gist of why Artemis looks so goofy at first glance. A tower built with a random fistful of Legos is gonna look a lot different than if you could select those Legos.

5 months between first two Saturn Vs, 6 months between first two shuttles, 4 months between the first two N1s, 6 months between the first two Falcon 9s. Seven months between the first two Starships is more than the average for this sort of thing but not significantly above average, especially given that the first mission blew up their launch pad and the legal challenges they faced. And especially considering that it is arguably the most ambitious rocket ever. We are looking at late March for flight 3 (applying typical delay constants), so that should be 4 months between flights 2 and 3, quite an acceleration.

Back to actual SpaceX discussion, I just remembered that it actually takes less propellant to fling one of these bad boys to Mars than it does to land on the Moon. Deep space communications, making the heat shield not fall apart and Mars capable, and near zero boiloff aren't trivial problems by any means, but once one of these lands on the Moon, I expect them to fling one at Mars at the next window (or at the next next window if the next one is really close). Most of the stuff required to do Mars will have been demonstrated at that point, and far less flights are required to do a Mars landing test than a Moon landing.

You know, if I had a nickel for every time we would go back and forth on this thread with someone who doesn't buy Starship and uses dark mode incompatible text, I'd have two nickels, which isn't a lot, but it is weird that it happened twice. Side note, would it be bad faith to dig up some of those old posts and tally how many of them have been proven wrong?

Okay. That I can believe. Thank you for answering the question. Big static fire series to catch issues and protect hardware, in a way that, per test and per booster, in an ideal world, is somewhat more effective at catching issues than flight testing. Then it becomes an economic problem. Cost (and feasibility) of a test stand versus cost of however many full stacks you end up exploding. I will add that startup and shutdown are the most iffy parts of such a test, steady state operation (although starship throttles around a lot so not a perfect comparison) is less likely to cause issues in most cases. A 10 second test will catch many of the issues that would also be caught on a longer test. You can't uncover most vibration and acceleration issues this way because the vibration and acceleration environments are different. So now it's an even smaller number of exploded stacks on that side of the equation due to doing the half measure testing that they are doing. Given the unique difficulties SpaceX faces on their plot of land, I could see that equation closing.

Man, we've had so much Falcon 9 saturation for the past several years that I forgot just how much of a sporty vehicle Falcon 9 is. Vulcan has like a 5 minute first stage burn, a 20-25 second stage separation sequence from cutoff to startup, and a 10 minute second stage burn. Not that it's bad, there are advantages to a sustainer architecture, but I just kind of haven't seen a sustainer rocket go up in a while (and had kind of assumed Vulcan was a tad sportier than it is).

If this goes right, a small wafer with my name engraved onto it (and an SD card with a picture I made on it) will be going to the Moon.

https://www.dropbox.com/scl/fo/3n441r6qea7ik41ncokov/h?rlkey=oep8frmrfyukl9hu8gxip8uc2&dl=0 I don't really like how workspaces are implemented and end up overwriting a lot of stuff accidentally, but some version of it should be in one of those two workspaces.

Just a reminder of the long struggle SpaceX had to get the EIS through and the subsequent legal battles over their sound suppression system, which was dumping a small amount of freshwater, comparable to rainfall, into the ocean. The assumption that the full duration stand gets through with no resistance is doing a lot of heavy lifting.

As others have noted. Flame trench: purpose is to put distance between the rocket and the nearest surface below it, and redirect exhaust outwards to prevent damage to both the rocket and the launch pad. An open on all sides flat deflector arguably performs this task better in most respects than a sloped open on one side deflector, all else held equal. Only real advantage a sloped deflector has is probably better Shockwave reflection characteristics. Powered stage separation: jury is out on this one but SpaceX is trying as hard as they can to find a method that does not require maintainence, refurbishment, or replacing components between flights. While a traditional ullage system would work, it violates that above constraint. A pusher like falcon 9 might also work but it would be stupidly heavy. They will do this if they need to but they are going to try everything else first. Full duration static fire is an economic problem. Is the cost of obtaining the land for, obtaining the permits for, constructing, building the transportation system for, and risking a catastrophic explosion of a full duration static fire stand that you are ideally only going to use one time if all goes well, or maybe once per booster, less than the cost of however many full stacks they blow up in flight due to issues that would have been uncovered during a full duration static fire plus the associated decrease in confidence due to in-flight failures? So far that is maybe one full stack on the other side of the equation, so far at least. IFT 1 could have possibly been prevented or mitigated by a full duration static fire, at the cost of the booster itself which would have likely been toast either way if they didn't shut it down early. So the only thing you are saving is S24 (which would probably be scrapped anyway working towards the next flight) and if you are extremely optimistic, maybe B7. Still, let's steel man this. Let's say 4/20, IFT 1 and IFT 2 were all destroyed explicitly by failures that would have been caught during a full duration static fire. Now we don't know the cost of what a test stand would be. I am also having trouble finding the original construction cost for the B2 test stand. However, I did find an OIG document saying that the renovation of B2 to get it ready for the SLS core stage, which mind you, doesn't even have that much thrust and isn't even a flight condition static fire (boosters are by far the majority of the thrust and vibration), on a site which the land was already owned and developed, was to cost 250 to 350 million dollars. Again, that is for modifying an already owned test stand for a far less powerful rocket than Starship. Granted, SpaceX has a knack for doing things cheaply. Maybe they could manage to do a starship scale test stand from scratch under their already strained environmental permits for 250 million dollars and without causing schedule slip. The question is now, are three starship stacks worth less than 250 million dollars? No, of course not, that would be ridiculous for these early flight articles to cost under 100 million each, although it is on the edge of possibility. Maybe these things cost 200M a piece right now, maybe 300, maybe 100, we have no reliable estimates. They were literally building their GSE the same way a while back, so maybe the raw tanks are ridiculously cheap by themselves, maybe the whole thing is 50M. But by most reasonable cost estimates for a full stack, SpaceX should probably have built a test stand. But do you see just how many assumptions we had to give there? Assuming that all three stacks could have succeeded if one had test fired? Of which only 1 was partially explicitly destroyed by something first stage engine boost phase related? Discounting the massive environmental statement related stuff they would have to do in order for this to get built? Assuming the costs for renovation of a less powerful stand are comparable to the new construction of a more powerful stand? This is an analysis so thoroughly biased towards a test stand and even then the test stand just barely comes out on top, well within the margin of hindsight.

I mean uh, I have like 50 bucks in a Robinhood account I made during COVID and nearly forgot about. I have $3.52 in fractional Tesla stock, so I guess I am a Musk shill.

It has had two flights. It is not unheard of for new rockets to fail a couple times and then go on to have successful careers, much less possibly the most ambitious rocket in history which was deliberately developed in a way in which more failures than average are expected. Now, if it still hasn't made orbit by flight 5 or 6, then that is cause for alarm. Even for normal rockets I wouldn't really start worrying until the third failure, although 2 would raise a few eyebrows.