5 ms·

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

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.

esjeon 3y ago
> 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.
- sneak 3y ago
  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".
- Gwypaas 3y ago
  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.
  - namaria 3y ago
    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.
    - kortilla 3y ago
      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.
      - namaria 3y ago
        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.
    - thatjoeoverthr 3y ago
      Cost and value are different things.
      - namaria 3y ago
        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.
        Dylan16807 3y ago
        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.
  - cromwellian 3y ago
    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.
    - mavhc 3y ago
      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.
  - simiones 3y ago
    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.
    - Dylan16807 3y ago
      At the same stage in development, SLS also had zero successful launches. So that's not very meaningful.
  - alexvoda 3y ago
    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 https://youtu.be/P_tGKxL6CLI?t=31
- leoedin 3y ago
  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.
  - davedx 3y ago
    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.
  - mft_ 3y ago
    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.
- 34679 3y ago
  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.
  - alexvoda 3y ago
    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.
tsimionescu 3y ago
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.
- XorNot 3y ago
  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.
  - tsimionescu 3y ago
    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.
    - XorNot 3y ago
      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.
alexvoda 3y ago
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.
- kortilla 3y ago
  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.
  - alexvoda 3y ago
    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° angle. Wedge, cone, pyramid, whatever shape works. Make everything out of steel if it works and is cheaper. Even RocketLab with their tiny Electron have a diverter. You can see it here: https://youtu.be/P_tGKxL6CLI?t=31 https://youtu.be/P_tGKxL6CLI?t=31
- inglor_cz 3y ago
  AFAIK flame diverters at Boca Chica would be technologically very challenging because of high ground water level, that is why they try other solutions.
  - alexvoda 3y ago

esjeon 3y ago

> 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.

sneak 3y ago
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".
Gwypaas 3y ago
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.
- namaria 3y ago
  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.
  - kortilla 3y ago
    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.
    - namaria 3y ago
      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.
  - thatjoeoverthr 3y ago
    Cost and value are different things.
    - namaria 3y ago
      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.
      - Dylan16807 3y ago
        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.
- cromwellian 3y ago
  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.
  - mavhc 3y ago
    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.
- simiones 3y ago
  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.
  - Dylan16807 3y ago
    At the same stage in development, SLS also had zero successful launches. So that's not very meaningful.
- alexvoda 3y ago
  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 https://youtu.be/P_tGKxL6CLI?t=31
leoedin 3y ago
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.
- davedx 3y ago
  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.
- mft_ 3y ago
  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.
34679 3y ago
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.
- alexvoda 3y ago
  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.

tsimionescu 3y ago

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.

XorNot 3y ago
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.
- tsimionescu 3y ago
  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.
  - XorNot 3y ago
    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.

alexvoda 3y ago

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.

kortilla 3y ago
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.
- alexvoda 3y ago
  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° angle. Wedge, cone, pyramid, whatever shape works. Make everything out of steel if it works and is cheaper. Even RocketLab with their tiny Electron have a diverter. You can see it here: https://youtu.be/P_tGKxL6CLI?t=31 https://youtu.be/P_tGKxL6CLI?t=31
inglor_cz 3y ago
AFAIK flame diverters at Boca Chica would be technologically very challenging because of high ground water level, that is why they try other solutions.
- alexvoda 3y ago