Anyone reading the headline could easily be misled: this was a massive success. Some context:
- This was the first "integrated test" of the Starship space craft with its booster
- The whole thing together was 120 meters tall
- It will be one order of magnitude larger than the current largest rocket in terms of carrying capacity (~150 tonnes if it needs to return the booster, 250 if it doesn't)
- There's 5 more of these being built right now so the next tests can be done soon
As a SpaceX fan reading through the post-launch analysis, this was definitely more of a success than the headline applies, but 'massive' is a stretch. Most commentary I'm seeing put it at a C or B-. It's true that there was a number of areas where the risk is now retired, but three engines out at launch with three more dropping out along the way hints that their engine design still isn't as reliable as it needs to be, several years and several engine test campaigns later.
SpaceX doesn't have a test stand where they can static-fire the booster at full power or duration, which feels like an interesting gap in their usual 'hardware-rich, test-often' iterative approach. I'm betting we see something like that roll out soon.
In fact it was a really amazing "engine out" test. The thing appeared to been shedding engines all the way to RUD. I imagine these engines were all early generation, might as well fly them, units. It's easy to imagine a calculus of "we're pretty sure X% of engines will fail, but we only need Y% for this flight, go ahead and fly them". But yeah, Musk once said there's a gigawatt of power going through these Raptor engines, that's not nothing.
Possible, but I don't think that's the full explanation. When the booster did a static test at half throttle, not all of the engines were able to light as well. SpaceX clearly chose to go ahead with a launch without waiting for a booster test with 100% ignition
That’s so hard to comprehend. I used to operate a 25ton crane. That’s less than half of 1% of Starship. That made me think it’s in the magnitude of a skyscraper. Apparently the Empire State Building is “only” 7 million pounds. What the fuck.
I guess "Largest rocket test in history successfully launched" doesn't generate enough traffic compared to the pessimistic "explodes minutes after launch."
If there are 5 more of these being built, how they will incorporate anything they learned during this failed attempt? Isn't that just a waste of money?
Considering that the failures don't appear to point to fundamental design flaws of the structure of the vehicle (if anything it kind of overperformed structurally with how long it just tumbled despite being a 100m tall, mostly hollow tube), they'll do it the same way you would fix/upgrade a car, by swapping out the bad parts.
The countdown process needs optimization. There are things missing and things which shouldn’t be there. We’re talking about speed of loading propellant, density of it, etc.
Then there’s software. So much software.
And a million other things. Rockets are complex, launching them doubly so.
Exactly. Falcon 9 took years and a couple dozen launches to optimize the countdown and flight profile to the current best in class general purpose medium weight launcher with the flight hardware remaining relatively constant (if for nothing else than certification reasons.)
Yeah, that's why you engineer, and test before trying to launch something like that.
There won't be any other attempt this year - I can bet my lunch money on this.
From watching the launch, my absolutely pulled from my butt guess is that something went wrong with the stage separation system, and that the explosion was deliberately triggered by the SpaceX team / triggered by automated guardrails when the mission didn't go according to parameters.
If that's true, then they can just fix whatever is wrong with the stage separation. And if it's something else, they can probably fix that too. Doesn't seem like it was anything unchangeably / structurally wrong with the entire craft.
There was a lot of wrong with the launch from the start - failed engines, destroyed pad, parts of the rocket flying off during the start. Yes, it's amazing that it went for as far as it did, but there is no way they can fix all of it quickly.
Everything you just listed is very probably all from a single root cause (the pad not being able to handle the force) and the fix could be as simple as using a bigger water deluge system / having a pad that isn't just a flat block of concrete / etc.
No only are there more being built, but this launch used engines that are already obsolete. They are learning stuff by building the rocket, by testing the components and by using them to do a test launch. They are trying to wring as much learning out of each step as possible.
SV first stage had 5 engines, vs 33 on the Starship's booster. Which I think answers your question :)
I don't know about other metrics for comparing engine efficiency. But the design requirements seem quite different here - they have to be restartable (not something the F1 engines on the SV had to worry about), probably more steerable, and able to throttle down to quite low power for landing. And presumably the fact that there's so many in an array also imposes its own constraints on the design.
> > > Is 2x thrust accomplished by scaling # of engines, or are the engines 'more-thrustful' per unit because of engineering advances?
> > SV first stage had 5 engines, vs 33 on the Starship's booster. Which I think answers your question :)
> it doesnt, please eLI5
I kinda suspect bad faith/trolling, but if not... 6.5 times the number of engines for twice the thrust means that you are getting less thrust per engine.
No trolling, but one of the the things I like to promote on HN is for people to ELI5 as much as possible, given the fact that our knowledge will evaporate over time... so I want people to, as much as possible, divulge as much as one can before they kick the can...
Yah, I just though this wasn't really subject matter expertise. It's not quite ELI"5", but I thought reasoning using ratios would be universal/intuitive.
Having a whole bunch of engines means loosing a few at launch won't end in disaster. That means you can pursue more high-risk, high-performance engine designs.
Starship at this point is mostly a shell. Internal human grade components aren't there yet. We have no idea what the final cost will be. But doesn't matter since NASA is the one paying.
> We have no idea what the final cost will be. But doesn't matter since NASA is the one paying.
The HLS contract SpaceX has gotten from NASA is a fixed-fee contract (like most contracts NASA gives out these days), so the final cost absolutely matters to SpaceX's bottom line. Anything they spend beyond the contracted amount they'll have to come up with themselves. A good example of this is Boeing, which is now booking losses on the Starliner program every quarter because it has gone over time and budget.
What? This makes zero sense. The cost to create a crew capsule is extremely well understood because they've been made countless times before. Also to imply the cost of that would put any dent whatsoever into the 5b vs 50b comparison is ridiculous. The cost of adding a crew capsule is a rounding error on total cost.
Actually we do know what NASA will be paying. Its all in the public contract. And its fixed cost, so it will not cost NASA more, no matter how often it blows up.
That doesn't give us details about how much it will cost SpaceX but its good information.
As impressive as Starship is or will be, Saturn V has definitely earned a place in the history books that cannot be undone. The first airplane flew in 1903. Just 64 years later, Saturn V was launched for the first time. The fact that it has taken us 56 more years since then to outdo it says a lot.
And by all excitement and history and nostalgia, if we are honest, the moon landing program was a massive waste of money. Like the Egyptian pyramids. The are impressive, yes ...
- This was the first "integrated test" of the Starship space craft with its booster
- The whole thing together was 120 meters tall
- It will be one order of magnitude larger than the current largest rocket in terms of carrying capacity (~150 tonnes if it needs to return the booster, 250 if it doesn't)
- There's 5 more of these being built right now so the next tests can be done soon