zolotiyeruki

I just saw Scott Manley's short, and it looks like there might be *two* RVac nozzle extensions damaged: (look at 0:25)

I had to hold back a belly laugh when I saw that, so as not to alert my boss next door...

It feels like there's an implication here that SpaceX's lack of communication means they aren't motivated to fix deficiencies. Seriously? In what world would SpaceX NOT want to fix design issues with Raptor?

Apollo was a great achievement, but it was hardly without its own failures: Apollo 1 - fire in the capsule, 3 dead. Apollo 6 - Two of the second stage engines shut down prematurely and the third stage did not reignite for its second burn, forcing an alternate mission. Wait, this sounds vaguely familiar...almost as if ground testing couldn't ensure engine reliability! Apollo 11 - Nav computer ran out of memory during descent. Also, ran pretty low on propellant. Apollo 13 - One second-stage engine shut down early, and of course there's that whole oxygen tank thing that happened... It's also worth pointing out that, adjusted for inflation, the Apollo program cost over $250 Billion (in 2020 dollars) over its 13-year run. You have to wonder what SpaceX would do with a freakin' quarter-trillion dollars.

1) You don't know that a Raptor failed on the boostback. All we know is that it didn't start. We have zero reason to believe that there's something wrong with that particular Raptor. In fact, since it fired up just fine for the landing burn, we have evidence that the Raptor worked just fine, and the failure-to-relight during boostback was due to something else. 2) You don't know that a Raptor failed catastrophically on SS. All we know so far is that it RUD'ed, and Musk's tweet about a leak above the false ceiling. Was it inside a Raptor? It's possible, but we have no evidence to support the conclusion you consistently jump to. 3) How is that "standard industry practice" working out these days? How well did it work for SLS? How well did it work for New Glenn? Both of them had second-stage issues, didn't they? All three are at a similar stage of development. BONG started in 2013, similar to Starship's early concept. SLS started in 2011, with a huge head start on propulsion. Starship (effectively re-)started development in 2017, when it was shrunk to a 9m diameter. Money spent so far? SS/SH: ~$7B. New Glenn? I'm not sure. SLS? hehe...$23 Billion and counting. Between the three, it's pretty clear that the "standard industry practice" isn't bringing the benefits you imagine it does.

I'm glad I'm not the only one who noticed flames coming from the hinge at T+07:55. No flames at that same location at +04:45. That's right near the engines. Yup, something blowed up good.

Was any reason given for the no-go on the catch?

In addition to everything else, I'm stoked about the idea of reusing stripped-down starships in space as the foundation for a space station. Picture a bunch of stripped-down (no tiles, ablative, or even flaps) Starships docked to a central hub like wheel spokes. The amount of volume for science or even space tourists would be spectacular.

I just noticed that one of the ten engines in the second ring isn't glowing and flaming like the other nine. The graphics on SpaceX's feed show all 10+3 engines running nominally for the landing burn, but something is different about this one:

Well, hello there, new wallpaper!

The California Coastal Commission has denied Space Force + SpaceX's application for 50 launches next year: https://www.politico.com/news/2024/10/10/california-reject-musk-spacex-00183371 It sounds like the commission didn't like a few things: --sonic booms --disturbance of wildlife --Musk's politics --SpaceX's labor practices

Well, so much for the "b-b-b-b-but they didn't do a full-duration static test fire!" nonsense.

So here's my take on it: Short version: SpaceX have the most to lose here, and I'm inclined to think that they're confident in their fixes to the earlier problems. Given SpaceX's rapid pace of development and iteration, and that regulatory approval seems to consistently stand on the critical path, it makes sense to test as many things as possible with each launch. In other words, if the FAA/EPA/FWS are going to drag their feet for months for every launch, you'd want to maximize the amount of test data you get with each launch. Longer version: A successful chopsticks-catch relies on all the various bits working correctly--engine relight, flaps, engine gimbals, control system, radar altimeter, GPS, etc. And all of that is moot unless the launch, separation, and boostback are nominal. Rather than take an overly-simplified perspective on it ("they haven't had a flawless soft ocean landing yet"), it's important to get into the details. First, you have to define the actual Bad Thing that could happen. Let's call it "damage to the tower." Second, you have to figure out what failures on the booster could cause that. Third, you have to eliminate (or accept the reduced risk from) those failures which have mitigations in place. For example, several of those failures (failed relight, GPS, a few others) are mitigated by having an initial trajectory that sends it offshore. Several others may be mitigated by FTS. Fourth, you look at the ask-yet-unmitigated failure modes. It appears that SpaceX have already proven out most of the systems--the aerodynamics, engine gimbals, control systems and GPS/altimeter stuff is fine, based on the previous launch. The propulsion systems appear to be the last piece (at least for the booster) that haven't had a perfect performance. SpaceX have surely addressed (or attempted to address) the issues that caused the engine fire on the last SuperHeavy, which means that the last known unmitigated failure modes have been addressed. Besides, you could make the argument that the successful water landing proved that the existing mitigations (e.g. throttling the other engines up to compensate) already work. And lastly, you have to evaluate the consequences of a failure. At this point the Bad Things that are left are some sort of failure in the chopsticks, and a fuel leak and fire at the engine end of the booster, with a potential structural failure and spectacular-but-brief fire. SpaceX have to test the chopsticks at some point, and I'd be willing to bet that SpaceX have a solution to the engine fire thing. So yes, they could do one more soft water landing to prove that all the systems work. At that point, however, they'd be chasing unknown unknowns, i.e. now-we're-just-guessing-what-might-go-wrong.

I'm pretty sure the Falcon 9 booster landing burns still start with a trajectory that misses the ASDS, with the landing burn adjusting the trajectory toward the ship. Compared to RTLS, the difference between the two trajectories can be pretty small. I don't recall--how many successful water landings did SpaceX perform before they started attempting to land on the droneships? It seems like it wasn't very many, certainly not a dozen. Just to add to this: if the relight succeeds, not only will the rocket be moving slower, but it will also have a lot less fuel in it when it gets to the chopsticks, in case something *does* go wrong after relight.

Keep in mind that when Superheavy (or Starship, for that matter) are being caught, there's not a whole lot of fuel left for any explosion. Sure, if the arms miss the catch, there'll still be quite a mess to clean up, but we're not talking Russian-ammo-dump levels of kaboom here.