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this post was submitted on 18 Nov 2023
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So the booster worked in that it achieved lift off and properly separated. Did the other stages complete their jobs? Because this looking like it's only a failure in the sense that the booster didn't do the cool we-live-in-the-future part of flipping itself over and landing.
The main focus of this test was stage separation. In that sense it was a roaring success. Also, looks like they managed not to trash the landing pad this time. So that will make it easier to get the next flight approved. But clearly there's still a long way to go.
Also demonstrated the flight termination systems, for both stages, it seems.
It appears they got their engine development under control too. Every one lit and burned effectively full duration, on both stages.
So basically they've fixed every issue displayed in the first flight I'd say.
Still some work to do in the not-blow-up department, though.
I mean, the entire purpose of the "blow up the ship" system is to blow it up, so that part worked correctly
Nope. Blew up uncontrolled.
Yes, but they blew up correctly. What they are saying is it is all new issues and the old ones are fixed. This is good for test vehicles.
Just for anyone wondering what blew up correctly means. The flight termination system didn't work properly on the 1st launch. Starship and the booster didn't separate and it tumbled in the air for too long. That puts people at risk as it might go out of the safe area.
This time, when whatever went wrong went wrong, the system triggered properly and both vehicles blew up.
They pick and chose what was the "focus" every time there's a launch. In reality focus is for everything to work. It didn't work this time either. It was worse the first time, but this time at the moment it looks better. Things worked out but second stage blew up in LEO which can cause all kinds of issues with debris and other satellites.
They've been pretty transparent about their expectations for these early test flights, and today's achievements match those expectations. For example, they didn't bother securing all the thermal tiles because they didn't really expect to survive re-entry.
The rocket didn't go to LEO. This was intentional, because they knew that this flight was unlikely to survive and they're as concerned about space debris as you are. All the debris either burned up or fell into the ocean.
Look up what LEO region is. It's everything beneath 2000km. But the point still stands, it was big ship with big explosion. You can't be sure things didn't get thrown outwards. Also, SpaceX is not exactly known for respecting the environment. In fact they've been constantly criticized about that.
But isn't the key aspect here "orbit"? I get that the FTS would lengthen the trajectory of some of the debris, but would it be enough to create a stable orbit? The original trajectory was going to splashdown near Hawaii.
I certainly agree that there are lots of environmental downsides to space exploration that are increasingly overlooked, I'm just not sure that there's anything extra egregious about this flight.
Well, I don't know if there is anything egregious about this either. Last time there was a spaceship test it was touted as a great success while tons of concrete flew in all directions destroying everything in their path from cameras to people's cars. Most importantly launch site is in the middle of the nature's reserve and agency in charge of that already filed a number of complaints because of their reckless destruction. "Genius" in charge said it was planed and only concrete was just fine, until it wasn't.
So I never trust what their PR says. Last time it was also planned and great success but they managed to get their launch license suspended. Am just not quick to jump to conclusions about whether this made any damage or not. Hopefully none of the debris managed to destroy anything.
Yeah, the concrete storm wasn't great last time. They did have some engineering reasons to believe it would work for a single launch, but it seems like there was more subsurface damage to the concrete than they realized. As far as I know the only property that was significantly damaged was related to the company, but I'm sure there were some smaller residential insurance claims for the dust.
Part of the reason Saturday's launch was delayed was so that more environmental assessments could be performed. A few weeks ago there some government scientists taking samples at the launch site for a baseline measurement to compare against in the future, and the entire project was reviewed by environmental regulators. So, those agencies were very involved in approving the launch license and SpaceX can't just do whatever the owner wants them to. I guess my point is that it's not strictly PR-speak, there really are qualified people making these decisions. But I agree that it's not great to have the facility in the middle of a sensitive wetland, and no doubt there was backdoor politicking. I wish SpaceX would do more to offset the harm they cause, but I still think the StarShip project does more good than harm.
I know you're just trying to be negative, I assume because of Musk (I hate him too). You're not being accurate, on purpose or otherwise it doesn't matter. It didn't even reach orbit. How did it blow up in Low Earth Orbit?
Am not trying just to be negative. Explosion disperses debris in all directions, and it wasn't a small explosion and it wasn't a small spaceship either but more to the point to quote wikipedia:
So I should have said LEO region, but still. Rocket exploded at 146km, which can pose issues. Hopefully it won't. But it remains to be seen. Kessler syndrome is a real threat.
It's about velocity, not altitude. The pieces from the explosion would need to get a fairly dramatic dv addition prograde to end up near orbital. The explosion seems pretty undirected, so the force will be spread in all directions, so most of the force won't be prograde. Even still, it can't be orbital. It'd need some other force added later on its trajectory or it eventually had to pass through the same altitude that the explosion happened, which is in-atmosphere and will cause fairly quick decay. There is no risk of Kessler syndrome. It could potentially have posed a risk to some very low satellites, but we'd already have seen that happen by now if it were going to.
Let's hope that's the case. It's unlikely I agree.
It seems that Starship, the second stage, experienced RUD from the automated FTS at around the time it was expected to shut off its engines.
Edit: RUD is Rapid Unscheduled Disassembly. Basically an explosion. FTS is Flight Termination System, which explodes a rocket if something goes wrong in a potentially dangerous way.
Which is an incremental improvement over the prior attempt. People mock these failures as though they have never built anything and have no concept that any step forward is a win when you are trying to do something that has never been done before. They got the smaller rockets working. It will just take time to get this giant one working.
Yeah but to get from here to a 99.99% reliability is a very very long way
Look at the Falcon rocket history. They started out at a very similar point, though at a smaller scale. And yet now they are comfortably human rated. They have landed the last 171 times in a row without fail, with another one coming this evening to add to that incredible number.
The guy at the helm is a terrible person, but this does not discredit the absolutely insane progress they have made.
What do you mean, never been done before?
We had satellites in space 70 years ago.
Delta clipper was pioneering reusable boosters in the 90’s.
SpaceX themselves have been recovering boosters for almost ten years now. They learned nothing from that?
I’m not saying it should work every time out of the gate, but they haven’t even reached orbit yet. And musk himself has said that starship being operational is critical to SpaceX and starlink if they don’t want the companies in serious financial trouble. So, it’s not like they’re taking their sweet time with these as incremental tests.
Fully reusable super-heavy rockets with multiple full stage combustion engines running on Methane have been done before? You mind sharing sources because I can't find any.
Closest thing I can think of is the Soviet N1 rocket (about 2/3 the thrust of Starship) which the Soviets really struggled with and ended up abandoning, and it wasn't even close to being reusable.
Didn't the N1 have a massive launch pad failure that we still don't know how many people it killed?
Can't find any reference to anyone dying or getting injured, but in terms of pad damage it definitely takes the cake.
The first Starship may have put a hole in the pad, but the N1 obliterated it.
You're comparing the world's first fully reusable rocket that also happens to be the world's most powerful operational rocket to old technology? The payload capacity of this vehicle is immense. There is not a single aspect of it that isn't brand new, from its proportions, engine power cycle, engine amount, construction materials, you can go on almost endlessly.
These incremental tests are what allow them to move at this incredible speed. Traditional rocket development doesn't take years, it takes decades. You have to consider that this isn't a government trying to outcompete another one, it's a private company. They are pushing the envelope with everything they're doing.
Nah, I mock this and I've built shit. The fact that musk is failing at stuff we've done before is hilarious.
Uh... Who has done this before?
We've been to the moon already.
What? 😂 This flight wasn't supposed to go to the moon. It's a test flight. They're developing the most powerful rocket to have ever flown and recover every part of it. They're also using a power cycle for the engine that has never been used before. So no, what SpaceX is doing has never been done before.
Musk is a twat but the people working at Spacex have shown themselves to be quite competent at what they do.
With an eight times higher injury rate? That's not competence.
What aspect of this "has never been done before"? Its a multi-stage rocket (NASA and the Soviets have been doing that for about seventy-ish years and the Nazi scientists we all recruited were doing it for even longer). The main innovations are material choice (which is debatable) and landing a rocket on a pad, which is mostly a function of having good computers.
Space flight is hard. That said, there is a very strong argument for being much less iterative. Especially when the quest for a reusable rocket involves constant spraying of wreckage across oceans and land.
In the respect that they're trying to get the world's largest rocket to separate and land itself. You know, be reusable.
Mentioned this in the other branch but:
The Space Shuttle was already a "reusable rocket". And the Saturn Vs would be recovered and refurbished, where possible. The main issue is that, much like with the space shuttle (and the "Starship" rockets): A LOT of wear and tear occurs during takeoff and re-entry. Reuse involves a LOT of repair and maintenance that often gets short cutted to save money. Which... is what leads to tragedies like Challenger and Columbia.
And I addressed the landing rockets on a pad. It is primarily a function of having MUCH better computers these days. And I was going to talk about how that has already been done but, while checking if Blue Origin also do it, I came up on this
https://www.discovermagazine.com/the-sciences/dc-x-the-nasa-rocket-that-inspired-spacex-and-blue-origin
So... it wasn't even "never been done before" a decade ago.
The big reason why we moved away from the Space Shuttle was... well, mostly Challenger and Columbia. It got that "This is bad technology" juju. But also, the costs of reuse are significant and drastically increase the cost per payload. I've read some good articles that argue we could make a MUCH cheaper and MUCH better space plane with modern tech but I am not qualified to assess that.
But... that also applies here. Having a rocket that lands itself is great and significantly reduces damage from recovery (whether it is thumping wrong in the ocean or getting damaged in transit). But that means you need a lot more fuel and a lot more weight for all the advanced maneuvering systems. And as you actually get out of the atmosphere, you now are increasing those costs considerably.
Whereas the old capsule system, while not sexy in the slightest, "works". Get the payload into space and then, when ready, use a minimal amount of fuel to de-orbit in a controlled manner and deploy a parachute once you aren't on fire anymore. But the main drawback to that is that the pod itself is incredibly limited in size and scope. With most modern missions expected to dock at a space station this matters a lot less. But I expect a return of a "space plane" design if we ever actually do a crewed mission to Mars.
The shuttle was hardly reusable. Yea, the airframe was, but after the first launches NASA discovered how fragile it really was.
Had they taken SpaxeX's approach, they would've discovered those issues much sooner and been able to correct them instead of mitigate them.
What we're seeing play out is an Agile project vs Waterfall project.
Agile, as the name implies, enables small, early course corrections so you don't waste effort and get stuck with something you weren't intending.
We're also seeing the difference between private sector risk management vs government. (Risk isn't just "exploding rocket", but risk to the investment of time, resources, opportunity, etc).
The space shuttle was a bus on boosters we had to fish out of the ocean. It was expensive and had a very limited cargo capacity.
Okay?
I mean, I very much forget what the "marketing" was. But like I mentioned above, the real value is the crew and scope of missions. You have a lot more space to move around and do Science! and whatever else.
The dragon capsule and falcon nine is a bus on boosters. It can only deliver people OR cargo. Not both.
The space shuttle could deliver crew, cargo, and mission modules in one launch. It was a very versatile and 75% reusable too. Compared to falcon which is only about 50% reusable.
The fastest turnaround time for a space shuttle was 54 days pre Challenger disaster and 88 days post Challenger disaster. It was very expensive and time consuming to reuse the space shuttle (they basically had to completely disassemble and reassemble the whole thing) which is one of the main reasons it has stopped flying. Falcon 9 on the other hand has a fastest turnaround time of 3 weeks. So not sure where you got your numbers from, but it seems to me that the Falcon 9 is a much better vehicle in terms of reuse.
You should look further into what that 25% difference is as far as cost and labor. Because that number is lying to you.
I'm pretty sure I remember reading that the cost to refurbish the shuttle boosters ended up costing as much or more than new ones.
Launching a rocket is even easier, it's mostly a function of having a big tank of propellant and powerful engines. A big rocket ? Just need a bigger tank and bigger engines.
RUD, aka “Rapid Unscheduled Disassembly”. I love how you can make “shit blew up in a way we didn’t expect” sound so mundane.