News for hackers. Stuff that matters.
Re:Was Starship’s Stage Zero a Bad Pad? by carabiner on Wednesday July 05, 2023 @03:56AM (#36597149)
They're working without precedent and I don't blame them for wanting to go for it in a full scale test. I don't know if you read the article, but the author, a civil engineer, makes the case that SpaceX deliberately went without a real pad just to see how bad the damage would be. They're planning to use a radically different pad for the next launch: a steel plate upsidedown showerhead with water spraying out.
Re:Was Starship’s Stage Zero a Bad Pad? by tsimionescu on Wednesday July 05, 2023 @04:07AM (#36597233)
If that is true, it's dangerously irresponsible, both to the protected environment they make their base in, and to themselves in terms of regulatory risks they are exposing themselves to.

It's quite likely that the launch will mean they have to litigate for their right to even keep using the Boca Chica site, given that both locals and environmental protection organizations are now aiming for their guts.

Re:Was Starship’s Stage Zero a Bad Pad? by XorNot on Wednesday July 05, 2023 @04:12AM (#36597269)
And none have a case. A worst case outcome of any rocket launch is a pad level detonation which levels the entire facility.

Against that, trashing their own launch pad is nothing. The most they've got is the dust plume.

Re:Was Starship’s Stage Zero a Bad Pad? by photonerd on Wednesday July 05, 2023 @04:41AM (#36597548)
They failed this federal test on basically every level.

So that’s a major case.

Re:Was Starship’s Stage Zero a Bad Pad? by tsimionescu on Wednesday July 05, 2023 @04:31AM (#36597451)
That's why you can't just "move fast and break things" when dealing with rockets. SpaceX is not allowed to launch a rocket that they don't have confidence will not explode on the pad. If one ever does, they will surely have to dismantle the site and move somewhere that is not a protected wildlife reservation.

In fact, they were also not really supposed to launch a rocket they didn't have confidence they could detonate if it veered off course - which they did (remember, the FTS failed to detonate the rocket on demand, and we were lucky that it was far enough away from anything after the attempt that it didn't put anyone in danger before structural forces destroyed it). The FAA investigation will determine whether they did their due diligence and simply made a mistake, or whether they acted irresponsibly on that front as well.

Re:Was Starship’s Stage Zero a Bad Pad? by XorNot on Wednesday July 05, 2023 @05:53AM (#36598094)
You're completely missing the point: if the rocket fired up its engines and immediately went off course from the pad, they would have to trigger the flight termination system at ground level which would cause the near fully loaded to rocket to explode on the pad.

If an area of a launch site is so valuable as to not be allowed to ever be at risk of mishap from the rocket launch, then the launch site should not be there.

However, the launch site is there and has already passed review for launch operations from that location. The occurrence of a launch failure or damage to the site does not suddenly mean re-evaluation on that basis: the default state of all rocket launches is that the rocket may explode upon ignition.

The environmental suit is motivated by people who have had an axe to grind with Elon Musk specifically (as opposed to SpaceX) unifying up with the regular environmentalist opposition, but neither has a valid claim here: a rocket failure resulting in destruction of the rocket and the facility is part and parcel of having any area performing launch operations.

Talking about "confidence" is irrelevant because that's not how you do a safety assessment: the assessment is "what happens when a failure happens, not if". You can only factor in "confidence" if your mitigations would depend strongly on an expected rate of failure being achieved.

Re:Was Starship’s Stage Zero a Bad Pad? by alexvoda on Wednesday July 05, 2023 @04:10AM (#36597262)
That will push water directly opposite of the thrust. I expect the water to be pushed backwards, the plate to melt and the exaust to be pushed into the water tank and maybe we will see a steam explosion.

There is a reason flame diverters are diverters instead of blockers. It's much much easier to just throw the exaust to the side instead of trying to fight it head on. Don't try to use force to block it, put a 45 degree angle and use geometry and physics to your advantage.

If they really want to experiment with unconventional solutions they could make a small scale test with a spent F9 and see if the idea is feasible. For what it's worth, even the F9 uses a flame diverter trench.

I get why they don't want to. It probably means modifying the tower too, probably to make it taller. But I foresee this shower head plate going badly.

Re:Was Starship’s Stage Zero a Bad Pad? by kortilla on Wednesday July 05, 2023 @04:34AM (#36597481)
The F9 uses the flame diverter trench because the pad it launches from already has it. Not because spacex built it.

They don’t need to test with a spent F9. They already did with raptor engines blasting a steel plate in mcgregor.

Re:Was Starship’s Stage Zero a Bad Pad? by alexvoda on Wednesday July 05, 2023 @05:28AM (#36597897)
But why would you ever put the plate at 0° when you can put it at 45°. Yes you need some height, but is that so onerous?

I am not saying they have to build something equivalent to the SLS/SST/Satun/Soyuz/Proton concrete pad infrastructure. Just put a 45°. Wedge, cone, pyramid, whatever shape works. Make everything out of steel if it works and is cheaper.

Re:Was Starship’s Stage Zero a Bad Pad? by inglor_cz on Wednesday July 05, 2023 @05:41AM (#36597992)
AFAIK flame diverters at Boca Chica would be technologically very challenging because of high ground water level, that is why they try other solutions.
Re:Was Starship’s Stage Zero a Bad Pad? by alexvoda on Wednesday July 05, 2023 @06:45AM (#36598459)
You don't need to dig to make the diverter. You can also build upwards. And I don't think you even have to make it of concrete. But from the tiny (Electron) to the super heavy (Saturn, N1, SLS) they all used some form of diverter. It doesn't have to be over engineered like the ones built by NASA. Even the Relativity Terran 1 which only ever launched once had a diverter.

Since the Super Heavy and the Starship are lifted into place by the tower instead of being rolled already assembled or rolled and erected from horizontal, it would be far easier for Super Heavy to have an above ground diverter compared to other rocket systems because it is no longer necessary to build the artificial hill and ramp on which to roll it. But the diverter is still needed.

Re:Was Starship’s Stage Zero a Bad Pad? by Gwypaas on Wednesday July 05, 2023 @10:00AM (#36600604)
> You don't need to dig to make the diverter. You can also build upwards.

And wait years for the soil to settle.

Re:Was Starship’s Stage Zero a Bad Pad? by alexvoda on Wednesday July 05, 2023 @10:38AM (#36601080)
You did not read the rest of the comment.
Re:Was Starship’s Stage Zero a Bad Pad? by mhio on Wednesday July 05, 2023 @08:45PM (#36609418)
Re:Was Starship’s Stage Zero a Bad Pad? by alexvoda on Thursday July 06, 2023 @04:26AM (#36612913)
That paragraph was hyperbolic sarcasm which I hoped would have been made clear by suggesting the tank would explode.

Note that even in the test you linked the plate was angled. This is not done just to redirect heat but in order too redirect the sound: https://physics.byu.edu/docs/publication/4678

Reflecting that towards the engines is probably suboptimal.

Re:Was Starship’s Stage Zero a Bad Pad? by esjeon on Wednesday July 05, 2023 @04:01AM (#36597185)
> They're working without precedent

It's not "without precedent" - they want to ignore the precedent and the entire concept of careful engineering for the sake of going fast (i.e. less money spent on step-by-step experiments). I think this is as irresponsible as the Titanic submarine. Hardware is not software.

Re:Was Starship’s Stage Zero a Bad Pad? by leoedin on Wednesday July 05, 2023 @04:14AM (#36597305)
The problem with this argument, when talking about space, is that precedent is often so extremely conservative and over-engineered that there's likely to be a huge middle ground between "good enough" and what NASA did in the 60s.

NASA built a launch pad with a flame diverter and water quenching system - and it worked! But now they have it, they're unlikely to test launches without it. Space X clearly think that there's a middle ground - something which is simpler, quicker and cheaper than the status quo, but which is good enough.

Clearly they failed - and arguably they were irresponsible not to do more tests. Given the environmental repercussions of failing, they probably should have started with something closer to precedent and worked iteratively to simplify it. But when you're talking about this sort of very low volume system (how many launch pads, total, are there in the world?), precedent is only worth so much. (It's also the reason so little progress was made in re-usable launchers until SpaceX came along).

Hardware is not software - I completely agree. But you can only make progress by testing hardware. Assumptions are rarely correct.

Re:Was Starship’s Stage Zero a Bad Pad? by davedx on Wednesday July 05, 2023 @04:50AM (#36597618)
Yup, apparently the pad at 39A was overdesigned too (for larger rockets than were launched from it).

Engineering is all about finding the tolerances. It's a difficult line to walk.

Re:Was Starship’s Stage Zero a Bad Pad? by mft_ on Wednesday July 05, 2023 @05:19AM (#36597810)
Broadly speaking, any individual or organisation working in a regulated industry is directly incentivised to either maintain the current status quo of conservatism, or increase it further.

Maintaining existing conservative approaches brings a huge amount of 'CYA' with little direct downside. Trying to even slightly roll back from a conservative position places all of the risk on the individual or individuals responsible, with a huge downside versus a small incremental upside that few will likely appreciate. It's mostly a thankless endeavour

I see this regularly in a different industry (with FDA, EMA) and it's what SpaceX are dealing with here. While I'm not arguing that their decision to launch with the existing stage 0 was correct, their decision to do something differently has introduced that much larger downside - further delays and potential censure from the FAA, and opprobrium from commentators and internet forums alike.

Re:Was Starship’s Stage Zero a Bad Pad? by Gwypaas on Wednesday July 05, 2023 @04:14AM (#36597303)
The alternative is the SLS, how many billions down the drain is that?

The true issue with the launch was the flight termination system taking 15-30s to trigger, which they have had to requalify since that is what protects the public from harm.

Re:Was Starship’s Stage Zero a Bad Pad? by namaria on Wednesday July 05, 2023 @04:21AM (#36597371)
Down the drain? The money has been used to pay people's labor and sourcing materials. That was demand attended to by highly sophisticated supply chains. SLS isn't some stone monument in the desert. It's a huge engineering undertaking.
Re:Was Starship’s Stage Zero a Bad Pad? by kortilla on Wednesday July 05, 2023 @04:32AM (#36597464)
Yes, a huge portion of the money was down the drain because of the significant waste. It enabled bloated, inefficient companies to stay alive supporting this one massive project.

SLS could have been done differently. Instead it was loaded with political favors demanding specific parts/suppliers.

Re:Was Starship’s Stage Zero a Bad Pad? by namaria on Wednesday July 05, 2023 @04:46AM (#36597596)
We can only know what was a dead end, waste or bloat in a complex systems pathways in retrospect. I would prefer for humanity's sake to see more avenues of technological advancement pursued rather then only those conforming to some(one's) definition of efficient/correct. SpaceX might be construed to be blowing private investment in some guy's grand vision of space exploration that might turn out to be simply vain. Time will tell. Deriding people exploring the edge of human progress because they don't fit with your values is presumptuous.
Re:Was Starship’s Stage Zero a Bad Pad? by thatjoeoverthr on Wednesday July 05, 2023 @04:50AM (#36597623)
Cost and value are different things.
Re:Was Starship’s Stage Zero a Bad Pad? by namaria on Wednesday July 05, 2023 @04:53AM (#36597646)
Someone's cost is another's value. Money didn't get burned. It moved along in the economy. It moving in ways you disapprove of is no basis to call it wrong. Unless you wanna parse the whole economy and veto things you don't agree with. Let me know how that turns out.
Re:Was Starship’s Stage Zero a Bad Pad? by Dylan16807 on Wednesday July 05, 2023 @05:43AM (#36598019)
The government can only spend so much money without things breaking down. When some of that money goes to bloat, that is waste. Despite it still being in the economy. And it's not about some kind of personal approval factor. If the government pays 2x what it could have paid for the same level of quality, that's entirely objective.
Re:Was Starship’s Stage Zero a Bad Pad? by namaria on Wednesday July 05, 2023 @06:53AM (#36598531)
If you're being objective with numerical measurements, care to provide source?

Bloat = waste, that is just circular logic. You're defining what you want to call waste as a synonym of waste. Nasa gets a budget and spend it on space missions, propulsion technology and launch vehicles. That money employs engineers and scientists and generates demand for high specs engineering firms and supply chains. The bang for the buck is this impact on the economy, stimulating education, R&D etc. Not the rocket that fits your definition of efficiency. Having more then one actively used propulsion vehicle with different technological approaches is a national investment in resilience.

Calling it bloat and inefficient because it takes more money per launch then another 100% experimental and unproven platform is incredibly myopic.

Re:Was Starship’s Stage Zero a Bad Pad? by Dylan16807 on Wednesday July 05, 2023 @07:17AM (#36598711)
I do not have a source for the generic example number.

If you want sources for government spending too much on things, those exist all over.

> Calling it bloat and inefficient because it takes more money per launch then another 100% experimental and unproven platform is incredibly myopic.

No, that's not what people are saying. The problem is that the main companies NASA contracts to are running in an extremely inefficient way and they get paid more when they waste money.

This is a problem that would exist even if SpaceX never became a company.

> That money employs engineers and scientists and generates demand for high specs engineering firms and supply chains. The bang for the buck is this impact on the economy, stimulating education, R&D etc.

The problem is the dollars that aren't going to engineering and R&D.

Dollars that just stimulate the economy are bloat when they're going to some big company out of a budget that's supposed to be doing things like exploring space. If you want to just send out dollars to stimulate the economy, send them out to people with low incomes and they'll have a much bigger impact.

Re:Was Starship’s Stage Zero a Bad Pad? by namaria on Wednesday July 05, 2023 @09:33AM (#36600232)
So you're just inventing numbers and making baseless claims? Got it. Stop wasting my time
Re:Was Starship’s Stage Zero a Bad Pad? by Dylan16807 on Wednesday July 05, 2023 @03:16PM (#36605627)
I think it was abundantly clear that "If the government pays 2x" was a generic hypothetical number.

Thank you for ignoring 95% of my post with that useless rejection.

Re:Was Starship’s Stage Zero a Bad Pad? by cromwellian on Wednesday July 05, 2023 @04:51AM (#36597627)
Have you looked at what SpaceX promised NASA for HLS? They need to be able to launch it and rapidly refuel it with 13 tankers. They’ve already spent a few billion, by the time they can reliably launch 13 refueling tankers in rapid succession and not destroy their stage 0, we could be taking $10-15 billion in dev costs putting Starship firmly in SLS territory.
Re:Was Starship’s Stage Zero a Bad Pad? by mavhc on Wednesday July 05, 2023 @05:43AM (#36598018)
Although if all goes well they'll still have all the future starships and engines afterwards. And a system that doesn't cost 100x as much to launch.
Re:Was Starship’s Stage Zero a Bad Pad? by simiones on Wednesday July 05, 2023 @05:12AM (#36597771)
And yet, the SLS has flied one successful mission and put something in lunar orbit without a hitch, while Starship failed in so many ways:

- it destroyed its pad

- it went off course as soon as it left the pad

- 8 out of 33 engines failed - one of which immediately after firing (causing it to go off course)

We'll see what the future brings, but for now its clearly SLS 1 - Starhsip 0. Given the amount of failures in the Starship exepriment, my bet is that we'll see at least 1 more successful SLS launch before the first Starship launch to reach orbit and back.

Re:Was Starship’s Stage Zero a Bad Pad? by Dylan16807 on Wednesday July 05, 2023 @05:40AM (#36597991)
At the same stage in development, SLS also had zero successful launches. So that's not very meaningful.
Re:Was Starship’s Stage Zero a Bad Pad? by alexvoda on Wednesday July 05, 2023 @05:48AM (#36598060)
No, there are options between the two extremes.

Nasa over engineered pad 39A and now they have a pad that can probably launch anything. But SpaceX with stage 0 did absolutely nothing even though most rockets in history used a diverter of some kind. A simpler and cheaper solution is welcome, but ignoring physics and doing nothing is just baffling (especially for the largest rocket ever). Even RocketLab with their tiny Electron have a diverter. You can see it here: https://youtu.be/P_tGKxL6CLI?t=31

Re:Was Starship’s Stage Zero a Bad Pad? by sneak on Wednesday July 05, 2023 @04:13AM (#36597288)
The Titan submarine was manned; errors resulted in lost lives.

No one was killed or even injured in the Starship test flight.

They are not comparable levels of "irresponsible".

Re:Was Starship’s Stage Zero a Bad Pad? by 34679 on Wednesday July 05, 2023 @06:05AM (#36598181)
Flame diverters are heavy, and none exist on Mars. It's safer to gather as much of that data as possible before going to Mars.
Re:Was Starship’s Stage Zero a Bad Pad? by alexvoda on Wednesday July 05, 2023 @07:15AM (#36598695)
And the Super Heavy will never go to Mars. Starship might. But how it launches from Mars is entirely speculation. For something like Starship to launch you need plenty of pad infrastructure anyway: fueling, chilling, etc.. If you can build that you can build a diverter no problem.

Also on Mars you need to dig anyway to create any kind of habitable environment due to radiation and you have no issues digging caused by the water table. So digging a diverter on Mars might even be easier then digging one at Boca Chica.