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My point would be that while SpaceX does save lots of money, it doesn't do so by producing cheap or less reliable rockets. It would never accept a failure rate

My point would be that while SpaceX does save lots of money, it doesn't do so by producing cheap or less reliable rockets. It would never accept a failure rate any different than anyone else because, in aerospace, that isn't really a thing. SpaceX can certainly blast forwards with different business practices and different tolerance for developmental risks, but the final product will not be fundamentally different than anyone else: near-perfect machines resulting in near-perfect performance. There will never be a "cheap" version of a commercial rocket with an accepted less-than-perfect failure rate. Spaceflight is an all-or-nothing game.

CydeWeys 4y ago
> My point would be that while SpaceX does save lots of money, it doesn't do so by producing cheap or less reliable rockets. It does though. During the development process. SpaceX will do five launches with lower reliability vehicles before the big launch providers will even do a single launch, and those five will have be cheaper in total. Of course, they aren't putting essential cargo (or god forbid people) on these higher risk test flights. By the time they're doing that they have developed certainty in the design.
- LeonB 4y ago
  > Of course, they aren't putting essential cargo (or god forbid people) on these higher risk test flights. A number of Tesla-related deaths can be attributed to Autopilot malfunction. Real people - really dead.
  - amanaplanacanal 4y ago
    Different company. This is about SpaceX.
  - martindbp 4y ago
    And statistically many more people would have died without AP. But you're correct in that Tesla is using the same playbook on FSD as SpaceX, launch HW (and SW) early and iterate often, and I'd bet they'll save way more lives trying to get to autonomy like SpaceX rather than like NASA (the Waymo approach).
    - yellowapple 4y ago
      > But you're correct in that Tesla is using the same playbook on FSD as SpaceX Except Tesla, unlike SpaceX, is willing to put passengers in its test vehicles. The SpaceX approach would be to let a bunch of FSD Teslas crash into things and each other before giving them payloads.
      - FireBeyond 4y ago
        Tesla is willing to put UNWILLING people in its tests (other road users, pedestrians).
        zaroth 4y ago
        I “unwillingly” have to share the road with people who murder 40,000 people a year with their vehicles. Thankfully we are developing the technology to get these reckless maniacs out of the driver’s seat.
      - martindbp 4y ago
        Putting someone in an experimental rocket is quite different from being essentially a safety driver required to pay attention and take over at any time. If you have an accident on FSD is is probably (though not always) your fault for not paying attention.
    - FireBeyond 4y ago
      > And statistically many more people would have died without AP. Citation needed. Not Tesla's "stats" that if the people compiling them completed anything more than high school statistics are intensely misleading. Comparing a subset of miles driven on the simplest and easiest roads (because the systems can't be used and are turned off) and comparing to accident stats across ALL roads is disingenuous to the extreme, and Tesla continues to tout it. Short of pulling over, humans don't have the opportunity to say "let's disengage, because it's a bit challenging", and then not have to worry about "counting" any accidents from there forward.
      - 4y ago
  - CydeWeys 4y ago
    I wasn't talking about Tesla though and I don't know why you assumed I'm pro-fake-Autopilot????
  - rjmunro 4y ago
    A number of Tesla related non-deaths can be attributed to Autopilot safety features working as promised. Tesla will argue that the number is higher, based on number of crashes per mile statistics. I'm not sure if that's true, but assuming for everyone who died due to an Autopilot failure, someone else survived a human error crash that didn't happen, would that be a good thing? What about if it was, for example, 10 people saved for every 1 killed?
    - dotancohen 4y ago
      I'm reminded of runaway trolleys.
jefftk 4y ago
> There will never be a "cheap" version of a commercial rocket with an accepted less-than-perfect failure rate. Spaceflight is an all-or-nothing game. Why? If you're launching people I see why you want near-perfect, but if you're launching something with a low replacement cost (ex: getting fuel to orbit to support other projects) it seems to me that as volumes get large enough eventually "use lower quality and accept a slightly higher probability of failure" starts to be cost effective.
- sandworm101 4y ago
  Because there is no way of building a cheaper rocket with a less reliability. Take aircraft. Does anyone deliberately build cargo aircraft with less reliability than passenger aircraft? Does anyone build a smaller airliner with less reliability than the big airliners because fewer lives are at risk in the smaller aircraft? No. All aircraft are designed and built to amazingly high standards because, in such as complex high-energy environment, there is no money to be saved by building less-than-perfect machines.
  - jrumbut 4y ago
    I'm with you on spaceflight but people definitely have built small cargo carrying UAVs to a lower standard than passenger aircraft. Such a thing is conceivable anyway.
    - sandworm101 4y ago
      Ya but smaller UAVs aren't operating in the same energy environment. They are small enough that them randomly dropping on people's houses doesn't matter much. Aerospace is about things large/fast/high enough that all failures put lives at risk.
  - Dylan16807 4y ago
    Okay, so you're not saying it has to be expensive, but almost the opposite? Perfect and slapdash have similar production cost, so properly designed rockets will all be just about perfect?
FormerBandmate 4y ago
The testing rocket is less reliable (and unmanned). The tests happen earlier in development
s1artibartfast 4y ago
I think it is a subtle difference. SpaceX does not have a difference in intended reliability, or a difference in design reliability. (At least for the rocket as a whole. One could argue that 33 engines allows lower engine reliability through redundancy) What they DO have is a significant difference in prototype reliability for live launch. This is clear when you look at their launch history.
- sandworm101 4y ago
  Or one could say that SpaceX has basically the same tolerance for failure as the traditional rocket companies had back in the 50s and 60s when they too were first learning to build rockets. That pre-launch "tolerance" is basically zero, with every post-launch failure being investigated as a mistake to be corrected rather than an acceptable cost of doing business.
  - s1artibartfast 4y ago
    >That pre-launch "tolerance" is basically zero I don't think that is accurate. There is a difference between 9%, 99%, and 99.999% confidence of success going into a launch. You can almost always delay builds and launces to run more simulations, tests, and studies and increase confidence. A simple example is SpaceX could have chosen to wait until they had a booster test with 100% engine ignition before moving on a full launch. Instead they choose move forward anyways without more stationary booster testing.
deleted 4y ago
[deleted]
AstixAndBelix 4y ago
>There will never be a "cheap" version of a commercial rocket with an accepted less-than-perfect failure rate. Spaceflight is an all-or-nothing game. substitute rocket and spaceflight with airplane and flight and see how that sounds
- sandworm101 4y ago
  Sounds exactly the same. There are no cheap aircraft. Everything that flies is subject to innumerable laws and regulations to ensure that it is built to exceedingly high standards. There is no such thing as a discount aircraft with lesser reliability. Some are cheaper than others but none are deliberately less-reliable, not in any fundamental way. Even ultralights have to abide many regulations.
  - monocasa 4y ago
    I can buy an ultralight with cash. I can't come close to a commercial aircraft with cash. Yes ultralights have some regulations, but even general aviation has less regulations resulting in cheaper aircraft, to say nothing of ultralights.
perryizgr8 4y ago
> it doesn't do so by producing cheap or less reliable rockets I saw in another comment that each SLS launch costs $2B. Do you think SpaceX spent $2B on this launch? I find it hard to believe.
labcomputer 4y ago
> My point would be that while SpaceX does save lots of money, it doesn't do so by producing cheap or less reliable rockets Indeed, if we assume that the each launch is an IID binomial coin flip (which isn’t really the right way to evaluate right-censored data), and observe (by reading Wikipedia) that SpaceX has had at least 450 successful Falcon 9 launches since the last in-flight failure, then they have at least five nines of reliability: 0.999995^450 ~= 449/450. Which appears to be an industry-leading stat. For context (excluding the Columbia re-entry failure), the space shuttle only had 4 nines: 0.99994^125 ~= 124/125
- stopping 4y ago
  I'm going to challenge those numbers: Using a posterior probability density function for a binomial distribution, the lower bound in Falcon 9 reliability is .9934 with 95% confidence (assuming 450/450 successful trials). The reliability of F9 could be much lower than five 9s and still reasonably give you 450/450 successful trials. There's only a 0.44% chance that F9 reliability is at least five 9's given the data.

CydeWeys 4y ago

> My point would be that while SpaceX does save lots of money, it doesn't do so by producing cheap or less reliable rockets. It does though. During the development process. SpaceX will do five launches with lower reliability vehicles before the big launch providers will even do a single launch, and those five will have be cheaper in total. Of course, they aren't putting essential cargo (or god forbid people) on these higher risk test flights. By the time they're doing that they have developed certainty in the design.

LeonB 4y ago
> Of course, they aren't putting essential cargo (or god forbid people) on these higher risk test flights. A number of Tesla-related deaths can be attributed to Autopilot malfunction. Real people - really dead.
- amanaplanacanal 4y ago
  Different company. This is about SpaceX.
- martindbp 4y ago
  And statistically many more people would have died without AP. But you're correct in that Tesla is using the same playbook on FSD as SpaceX, launch HW (and SW) early and iterate often, and I'd bet they'll save way more lives trying to get to autonomy like SpaceX rather than like NASA (the Waymo approach).
  - yellowapple 4y ago
    > But you're correct in that Tesla is using the same playbook on FSD as SpaceX Except Tesla, unlike SpaceX, is willing to put passengers in its test vehicles. The SpaceX approach would be to let a bunch of FSD Teslas crash into things and each other before giving them payloads.
    - FireBeyond 4y ago
      Tesla is willing to put UNWILLING people in its tests (other road users, pedestrians).
      - zaroth 4y ago
        I “unwillingly” have to share the road with people who murder 40,000 people a year with their vehicles. Thankfully we are developing the technology to get these reckless maniacs out of the driver’s seat.
    - martindbp 4y ago
      Putting someone in an experimental rocket is quite different from being essentially a safety driver required to pay attention and take over at any time. If you have an accident on FSD is is probably (though not always) your fault for not paying attention.
  - FireBeyond 4y ago
    > And statistically many more people would have died without AP. Citation needed. Not Tesla's "stats" that if the people compiling them completed anything more than high school statistics are intensely misleading. Comparing a subset of miles driven on the simplest and easiest roads (because the systems can't be used and are turned off) and comparing to accident stats across ALL roads is disingenuous to the extreme, and Tesla continues to tout it. Short of pulling over, humans don't have the opportunity to say "let's disengage, because it's a bit challenging", and then not have to worry about "counting" any accidents from there forward.
    - 4y ago
- CydeWeys 4y ago
  I wasn't talking about Tesla though and I don't know why you assumed I'm pro-fake-Autopilot????
- rjmunro 4y ago
  A number of Tesla related non-deaths can be attributed to Autopilot safety features working as promised. Tesla will argue that the number is higher, based on number of crashes per mile statistics. I'm not sure if that's true, but assuming for everyone who died due to an Autopilot failure, someone else survived a human error crash that didn't happen, would that be a good thing? What about if it was, for example, 10 people saved for every 1 killed?
  - dotancohen 4y ago
    I'm reminded of runaway trolleys.

jefftk 4y ago

> There will never be a "cheap" version of a commercial rocket with an accepted less-than-perfect failure rate. Spaceflight is an all-or-nothing game. Why? If you're launching people I see why you want near-perfect, but if you're launching something with a low replacement cost (ex: getting fuel to orbit to support other projects) it seems to me that as volumes get large enough eventually "use lower quality and accept a slightly higher probability of failure" starts to be cost effective.

sandworm101 4y ago
Because there is no way of building a cheaper rocket with a less reliability. Take aircraft. Does anyone deliberately build cargo aircraft with less reliability than passenger aircraft? Does anyone build a smaller airliner with less reliability than the big airliners because fewer lives are at risk in the smaller aircraft? No. All aircraft are designed and built to amazingly high standards because, in such as complex high-energy environment, there is no money to be saved by building less-than-perfect machines.
- jrumbut 4y ago
  I'm with you on spaceflight but people definitely have built small cargo carrying UAVs to a lower standard than passenger aircraft. Such a thing is conceivable anyway.
  - sandworm101 4y ago
    Ya but smaller UAVs aren't operating in the same energy environment. They are small enough that them randomly dropping on people's houses doesn't matter much. Aerospace is about things large/fast/high enough that all failures put lives at risk.
- Dylan16807 4y ago
  Okay, so you're not saying it has to be expensive, but almost the opposite? Perfect and slapdash have similar production cost, so properly designed rockets will all be just about perfect?

FormerBandmate 4y ago

The testing rocket is less reliable (and unmanned). The tests happen earlier in development

s1artibartfast 4y ago

I think it is a subtle difference. SpaceX does not have a difference in intended reliability, or a difference in design reliability. (At least for the rocket as a whole. One could argue that 33 engines allows lower engine reliability through redundancy) What they DO have is a significant difference in prototype reliability for live launch. This is clear when you look at their launch history.

sandworm101 4y ago
Or one could say that SpaceX has basically the same tolerance for failure as the traditional rocket companies had back in the 50s and 60s when they too were first learning to build rockets. That pre-launch "tolerance" is basically zero, with every post-launch failure being investigated as a mistake to be corrected rather than an acceptable cost of doing business.
- s1artibartfast 4y ago
  >That pre-launch "tolerance" is basically zero I don't think that is accurate. There is a difference between 9%, 99%, and 99.999% confidence of success going into a launch. You can almost always delay builds and launces to run more simulations, tests, and studies and increase confidence. A simple example is SpaceX could have chosen to wait until they had a booster test with 100% engine ignition before moving on a full launch. Instead they choose move forward anyways without more stationary booster testing.

deleted 4y ago

[deleted]

AstixAndBelix 4y ago

>There will never be a "cheap" version of a commercial rocket with an accepted less-than-perfect failure rate. Spaceflight is an all-or-nothing game. substitute rocket and spaceflight with airplane and flight and see how that sounds

sandworm101 4y ago
Sounds exactly the same. There are no cheap aircraft. Everything that flies is subject to innumerable laws and regulations to ensure that it is built to exceedingly high standards. There is no such thing as a discount aircraft with lesser reliability. Some are cheaper than others but none are deliberately less-reliable, not in any fundamental way. Even ultralights have to abide many regulations.
- monocasa 4y ago
  I can buy an ultralight with cash. I can't come close to a commercial aircraft with cash. Yes ultralights have some regulations, but even general aviation has less regulations resulting in cheaper aircraft, to say nothing of ultralights.

perryizgr8 4y ago

> it doesn't do so by producing cheap or less reliable rockets I saw in another comment that each SLS launch costs $2B. Do you think SpaceX spent $2B on this launch? I find it hard to believe.

labcomputer 4y ago

> My point would be that while SpaceX does save lots of money, it doesn't do so by producing cheap or less reliable rockets Indeed, if we assume that the each launch is an IID binomial coin flip (which isn’t really the right way to evaluate right-censored data), and observe (by reading Wikipedia) that SpaceX has had at least 450 successful Falcon 9 launches since the last in-flight failure, then they have at least five nines of reliability: 0.999995^450 ~= 449/450. Which appears to be an industry-leading stat. For context (excluding the Columbia re-entry failure), the space shuttle only had 4 nines: 0.99994^125 ~= 124/125

stopping 4y ago
I'm going to challenge those numbers: Using a posterior probability density function for a binomial distribution, the lower bound in Falcon 9 reliability is .9934 with 95% confidence (assuming 450/450 successful trials). The reliability of F9 could be much lower than five 9s and still reasonably give you 450/450 successful trials. There's only a 0.44% chance that F9 reliability is at least five 9's given the data.