4 ms·

SpaceX actually got very close to sticking this landing. Sea conditions were reasonably rough, with 3-meter waves. It's also the first time SpaceX launches in f

by marvin 11y ago

SpaceX actually got very close to sticking this landing. Sea conditions were reasonably rough, with 3-meter waves. It's also the first time SpaceX launches in fog, IIRC. Everything about the landing except the stuck leg seemed to be perfect. So IMHO, the fact that the rocket exploded is not the most pertinent fact about this experiment. The main piece of news is that SpaceX is exceedingly likely to be able to recover rocket boosters intact from sea, even in non-perfect weather conditions.

noobie 11y ago
>It's also the first time SpaceX launches in fog Musk said the "root cause may have been ice buildup due to condensation from heavy fog at liftoff."
- ridgeguy 11y ago
  Ice buildup on cryogenic components has been a problem with earlier private launch attempts from VAFB. See [1]for a frozen main LOX valve that didn't fully open due to ice frozen out of humid air. [1] https://en.wikipedia.org/wiki/American_Rocket_Company https://en.wikipedia.org/wiki/American_Rocket_Company
smoyer 11y ago
As a former gymnast, I like the sticking the landing analogy but a human (even on an unstable mat) has far more control over their balance point (we do much of our balancing by bending at the waist - if only the rocket had one). In any case, I agree that this was very close. I've also spent a reasonable amount of time on "big water" and was specifically watching the attitude of the landing deck with respect to the horizon. I didn't see much movement of the barge (but that doesn't mean there wasn't some instantaneous movement that together with the force of landing exceeded the leg's load rating). The other thing that's struck me is that the SSTO advocates could end up becoming irrelevant. Who's going to argue we need SSTO at all if we can recover and reuse all the stages anyway? Multiple stages will remain dramatically more efficient (Yes - I know we don't get space planes with two hour flight times from New York to Tokyo quite as easily). Finally ... I just have to say "I LOVE THIS". I remember as a child watching the Apollo missions and, as an engineer, I haven't been this excited about a project for a long time. Isn't this exactly the type of thing we can rally humanity around? Who's going to argue that it's not a great accomplishment?
- rtkwe 11y ago
  The Falcon 9 isn't totally reusable not does it plan to be. It still has a non-recoverable second stage so it's not quite to the point of a SSTO.
  - smoyer 11y ago
    Are you sure that there's not a plan to recover the second stage once they've consistently been recovering the first stage? (I'm assuming that would be part of the road-map).
    - deleted 11y ago
      [deleted]
    - CarolineW 11y ago
      From Wikipedia: The project's long-term objectives include returning a launch vehicle first stage to the launch site in minutes and to return a second stage to the launch pad following orbital realignment with the launch site and atmospheric reentry in up to 24 hours. https://en.wikipedia.org/wiki/SpaceX_reusable_launch_system_development_program https://en.wikipedia.org/wiki/SpaceX_reusable_launch_system_... However, from other sources: SpaceX would love to recover the second stage, which they had planned. But it sounds like they have given up on that. http://space.stackexchange.com/questions/7814/what-happens-to-the-falcon-9-second-stage-after-payload-separation http://space.stackexchange.com/questions/7814/what-happens-t... What they are referring to there is a transcript I have been unable to access. It's here: http://shitelonsays.com/transcript/elon-musk-at-mits-aeroastro-centennial-part-1-of-6-2014-10-24 http://shitelonsays.com/transcript/elon-musk-at-mits-aeroast... More discussion about it all here: https://www.quora.com/Could-SpaceX-feasibly-recover-the-second-stage-of-a-rocket-in-addition-to-the-first-stage https://www.quora.com/Could-SpaceX-feasibly-recover-the-seco... https://www.reddit.com/r/spacex/comments/1zg7zm/how_soon_can_we_hope_for_2nd_stage_reuse/ https://www.reddit.com/r/spacex/comments/1zg7zm/how_soon_can... https://www.google.co.uk/search?q=space-X+recovering+second+stage https://www.google.co.uk/search?q=space-X+recovering+second+...
dwc 11y ago
> Everything about the landing except the stuck leg seemed to be perfect. And there's the issue: it only takes a tiny bit of imperfect to ruin a landing. I do think that SpaceX is going to get to the point where they are recovering enough of their rockets to make it pay off. But there will probably always be a significant chance that some little thing will go wrong. Don't be fooled later by "we've landed 5 in a row" about that.
- thatswrong0 11y ago
  I guess it depends on what you mean by significant. It's true that, inherently, space flight is risky business.[0] This is new technology, so of course they are going to continue to uncover weaknesses even much further down the line once they start hitting a higher success rate. But for the tiny bit of imperfect: the same could have been said for the space shuttle, and that had people in it. And its fragility was a fundamental to its design (it rode exposed on the fuel tank with its critically important heat-absorbing tiles). And the shuttle still had a decent success rate! I would argue that these failures are less fundamental to the design of the rocket. And the difference is that if, in the future, you have that 1/100 failure on landing, it's only a loss from a cost perspective, not a human one. [0] http://i.imgur.com/ei3h1B7.png http://i.imgur.com/ei3h1B7.png
- martinald 11y ago
  This is very, very, early days. I'm sure you could have side the same about 'normal' flight, loads and loads of failures, then getting it to the '5 in the row', then a bunch of screwups. Now jet flight across the oceans in often horrendous conditions is 99.999% safe (ish).
- Htsthbjig 11y ago
  The number of things that could go wrong is limited. The will learn all of them. The same happened with airplanes. Just something so simple as breaking sound barrier control inversion meant hundreds of pilots dying until someone figured it out.. Thanks to automation and telemetry, SpaceX is learning fast without killing anyone. In the past it was hard to analyze what went wrong when the pilot did not survive.
ctdonath 11y ago
There's a pragmatic difference between recovering the booster over some period of time, vs literally parking the booster right where it took off & ready to re-launch within hours/minutes.
- tempestn 11y ago
  I can't see re-launching withing hours any time in the foreseeable future. Even once they're proven reusable each booster will need significant inspection and likely maintenance before being ready to re-launch.
  - mmcconnell1618 11y ago
    The same stage probably won't be ready to relaunch but imagine an assembly line of reusable stages that land at the same facility where they take off and then head right into a service center. With enough stages in rotation you can have a near continuous stream of launches.
  - msandford 11y ago
    > I can't see re-launching withing hours any time in the foreseeable future. Even once they're proven reusable each booster will need significant inspection and likely maintenance before being ready to re-launch. Initially, yes of course. But if they manage to launch a stage 100 times and it always passes inspection and etc, etc etc it's not impossible that eventually you'll get to the point where you only inspect every 2 launches, every 3 launches, every 5 or 10 launches. Once the ride to orbit costs: $100million/X + $Ymillion + $Zthousand where X is the number of reuses Y is the second stage cost Z is the fuel, launch fees, refurb, etc There's an experience curve (https://en.wikipedia.org/wiki/Experience_curve_effects https://en.wikipedia.org/wiki/Experience_curve_effects) that shows you how much you'll save as you build more and more units and it's entirely possible that the (expendable) second stage could eventually get very cheap to the point where you don't want to spend $1 million (or whatever) going over the rocket for every launch. If you're launching priceless (or very, very expensive) fancy space telescopes that cost tens of billions then the cost of a failed launch is very, very high. But if you're launching a bunch of food and you can lob another shot next week if it fails, and everything else is cheap enough, it might someday make sense. Before you ask me if I'm crazy, please understand that airplanes do exactly this; you have to get your engines overhauled every few thousand hours and I'm sure there are inspections, but they don't tear the plane down and rebuild it after every flight. Once systems get reliable enough, that's a thing.
niels_olson 11y ago
3-meter waves?! For context, once those hit the surf zone they stand up a bit more. Here's what that looks like when it's breaking http://www.surfline.com/forecasters/blog/12_foot1.gif http://www.surfline.com/forecasters/blog/12_foot1.gif (source: http://www.surfline.com/surf-science/wave-heights---forecaster-blog_22495/ http://www.surfline.com/surf-science/wave-heights---forecast...)

by marvin 11y ago

noobie 11y ago

>It's also the first time SpaceX launches in fog Musk said the "root cause may have been ice buildup due to condensation from heavy fog at liftoff."

ridgeguy 11y ago
Ice buildup on cryogenic components has been a problem with earlier private launch attempts from VAFB. See [1]for a frozen main LOX valve that didn't fully open due to ice frozen out of humid air. [1] https://en.wikipedia.org/wiki/American_Rocket_Company https://en.wikipedia.org/wiki/American_Rocket_Company

smoyer 11y ago

As a former gymnast, I like the sticking the landing analogy but a human (even on an unstable mat) has far more control over their balance point (we do much of our balancing by bending at the waist - if only the rocket had one). In any case, I agree that this was very close. I've also spent a reasonable amount of time on "big water" and was specifically watching the attitude of the landing deck with respect to the horizon. I didn't see much movement of the barge (but that doesn't mean there wasn't some instantaneous movement that together with the force of landing exceeded the leg's load rating). The other thing that's struck me is that the SSTO advocates could end up becoming irrelevant. Who's going to argue we need SSTO at all if we can recover and reuse all the stages anyway? Multiple stages will remain dramatically more efficient (Yes - I know we don't get space planes with two hour flight times from New York to Tokyo quite as easily). Finally ... I just have to say "I LOVE THIS". I remember as a child watching the Apollo missions and, as an engineer, I haven't been this excited about a project for a long time. Isn't this exactly the type of thing we can rally humanity around? Who's going to argue that it's not a great accomplishment?

rtkwe 11y ago
The Falcon 9 isn't totally reusable not does it plan to be. It still has a non-recoverable second stage so it's not quite to the point of a SSTO.
- smoyer 11y ago
  Are you sure that there's not a plan to recover the second stage once they've consistently been recovering the first stage? (I'm assuming that would be part of the road-map).
  - deleted 11y ago
    [deleted]
  - CarolineW 11y ago
    From Wikipedia: The project's long-term objectives include returning a launch vehicle first stage to the launch site in minutes and to return a second stage to the launch pad following orbital realignment with the launch site and atmospheric reentry in up to 24 hours. https://en.wikipedia.org/wiki/SpaceX_reusable_launch_system_development_program https://en.wikipedia.org/wiki/SpaceX_reusable_launch_system_... However, from other sources: SpaceX would love to recover the second stage, which they had planned. But it sounds like they have given up on that. http://space.stackexchange.com/questions/7814/what-happens-to-the-falcon-9-second-stage-after-payload-separation http://space.stackexchange.com/questions/7814/what-happens-t... What they are referring to there is a transcript I have been unable to access. It's here: http://shitelonsays.com/transcript/elon-musk-at-mits-aeroastro-centennial-part-1-of-6-2014-10-24 http://shitelonsays.com/transcript/elon-musk-at-mits-aeroast... More discussion about it all here: https://www.quora.com/Could-SpaceX-feasibly-recover-the-second-stage-of-a-rocket-in-addition-to-the-first-stage https://www.quora.com/Could-SpaceX-feasibly-recover-the-seco... https://www.reddit.com/r/spacex/comments/1zg7zm/how_soon_can_we_hope_for_2nd_stage_reuse/ https://www.reddit.com/r/spacex/comments/1zg7zm/how_soon_can... https://www.google.co.uk/search?q=space-X+recovering+second+stage https://www.google.co.uk/search?q=space-X+recovering+second+...

dwc 11y ago

> Everything about the landing except the stuck leg seemed to be perfect. And there's the issue: it only takes a tiny bit of imperfect to ruin a landing. I do think that SpaceX is going to get to the point where they are recovering enough of their rockets to make it pay off. But there will probably always be a significant chance that some little thing will go wrong. Don't be fooled later by "we've landed 5 in a row" about that.

thatswrong0 11y ago
I guess it depends on what you mean by significant. It's true that, inherently, space flight is risky business.[0] This is new technology, so of course they are going to continue to uncover weaknesses even much further down the line once they start hitting a higher success rate. But for the tiny bit of imperfect: the same could have been said for the space shuttle, and that had people in it. And its fragility was a fundamental to its design (it rode exposed on the fuel tank with its critically important heat-absorbing tiles). And the shuttle still had a decent success rate! I would argue that these failures are less fundamental to the design of the rocket. And the difference is that if, in the future, you have that 1/100 failure on landing, it's only a loss from a cost perspective, not a human one. [0] http://i.imgur.com/ei3h1B7.png http://i.imgur.com/ei3h1B7.png
martinald 11y ago
This is very, very, early days. I'm sure you could have side the same about 'normal' flight, loads and loads of failures, then getting it to the '5 in the row', then a bunch of screwups. Now jet flight across the oceans in often horrendous conditions is 99.999% safe (ish).
Htsthbjig 11y ago
The number of things that could go wrong is limited. The will learn all of them. The same happened with airplanes. Just something so simple as breaking sound barrier control inversion meant hundreds of pilots dying until someone figured it out.. Thanks to automation and telemetry, SpaceX is learning fast without killing anyone. In the past it was hard to analyze what went wrong when the pilot did not survive.

ctdonath 11y ago

There's a pragmatic difference between recovering the booster over some period of time, vs literally parking the booster right where it took off & ready to re-launch within hours/minutes.

tempestn 11y ago
I can't see re-launching withing hours any time in the foreseeable future. Even once they're proven reusable each booster will need significant inspection and likely maintenance before being ready to re-launch.
- mmcconnell1618 11y ago
  The same stage probably won't be ready to relaunch but imagine an assembly line of reusable stages that land at the same facility where they take off and then head right into a service center. With enough stages in rotation you can have a near continuous stream of launches.
- msandford 11y ago
  > I can't see re-launching withing hours any time in the foreseeable future. Even once they're proven reusable each booster will need significant inspection and likely maintenance before being ready to re-launch. Initially, yes of course. But if they manage to launch a stage 100 times and it always passes inspection and etc, etc etc it's not impossible that eventually you'll get to the point where you only inspect every 2 launches, every 3 launches, every 5 or 10 launches. Once the ride to orbit costs: $100million/X + $Ymillion + $Zthousand where X is the number of reuses Y is the second stage cost Z is the fuel, launch fees, refurb, etc There's an experience curve (https://en.wikipedia.org/wiki/Experience_curve_effects https://en.wikipedia.org/wiki/Experience_curve_effects) that shows you how much you'll save as you build more and more units and it's entirely possible that the (expendable) second stage could eventually get very cheap to the point where you don't want to spend $1 million (or whatever) going over the rocket for every launch. If you're launching priceless (or very, very expensive) fancy space telescopes that cost tens of billions then the cost of a failed launch is very, very high. But if you're launching a bunch of food and you can lob another shot next week if it fails, and everything else is cheap enough, it might someday make sense. Before you ask me if I'm crazy, please understand that airplanes do exactly this; you have to get your engines overhauled every few thousand hours and I'm sure there are inspections, but they don't tear the plane down and rebuild it after every flight. Once systems get reliable enough, that's a thing.

niels_olson 11y ago

3-meter waves?! For context, once those hit the surf zone they stand up a bit more. Here's what that looks like when it's breaking http://www.surfline.com/forecasters/blog/12_foot1.gif http://www.surfline.com/forecasters/blog/12_foot1.gif (source: http://www.surfline.com/surf-science/wave-heights---forecaster-blog_22495/ http://www.surfline.com/surf-science/wave-heights---forecast...)