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What are the odds of Starship working? It seems really complex. And that last phase where the ship flips vertical from the bellyflop, looks insane for human pa

What are the odds of Starship working? It seems really complex. And that last phase where the ship flips vertical from the bellyflop, looks insane for human passengers inside. How many G’s is that maneuver pulling? SN8 appears 90% successful, but I’m wondering if that remaining 10% is the killer. As they say: You spend 10% of your time, solving 90% of your problem. And then you spend 90% of your time, solving the last 10% of your problem. Between high speed re-entry, and thermal protections, I wonder how well the Starship design was modeled, to handle hypersonic re-entry speeds. It appears to be a very large spacecraft that’s re-entering the atmosphere at very high speeds. If it succeeds, then maybe it’ll open up space travel and make it cheaper. If not, then well, nice try. Back to the drawing board. But maybe, we’ll see results soon enough, with SN9.

andrewflnr 6y ago
Gs come from acceleration, either straight line or centripetal. I don't think there is enough control authority in starship's fins to create much centripetal acceleration the way a fighter jet's wings can. If the rocket is capable of it, it would do the same whether it was belly-flopping or dropping straight down the whole way. Any passengers will certainly get an inner-ear workout, but I can't imagine how the flip, more or less around the rocket's own axis, could contribute significantly to G-loading.
- christophilus 6y ago
  You’re still spinning violently and then snapping to a stop. I wonder if the payload could be designed to counter that in some way? If it was suspended in a liquid, that might work, but that’s unrealistic.
juanbyrge 6y ago
I don’t mean to trivialize what SpaceX is accomplishing, but maybe we are overestimating the degree of difficulty of building rockets in the 21st century, given the advances in technology over the past few decades? With the immense improvement in compute power, materials, accelerometers, welding techniques, etc.. since the 60s, maybe SpaceX was the first to recognize that building rockets is not as hard as it used to be?
- nickik 6y ago
  Well, we actually have a large amount of companies trying to do it. Like 40-60 different companies. Not to mention government projects. Of all of those, only RocketLab has managed to do it, and their rocket is basically as tiny as you can build a orbital rocket. SpaceX did an orbital rocket bigger then RocketLab in 2008. RocketLab doesn't yet have real competition, despite many billions invested. SpaceX at the same time went from the tiny Falcon 1 to a gigantic Starship program more ambitious then Saturn V and Apollo. I think we do our self a dissevers by just saying 'well, we have computers now so its easy'. Given how many people have tried and how many have failed or taken many, many years longer then they thought, it is clearly not easy at all. And mass producing them reliably is even harder. SpaceX and Elon Musk are clearly special and unique. Something we have never seen before.
  - christophilus 6y ago
    ULA is doing it, and seems to be a commercial success. I’m genuinely curious why ULA doesn’t get more publicity.
    - nickik 6y ago
      ULA is not new, its basically Boeing and Lockheed Martin getting together to form a monopoly. The rockets themselves have a lot of legacy going back 60 years. These rockets were developed for the US government and ULA itself has never created its own rocket. I also didn't talk about China or Indian launch who are also doing it.
  - blackrock 6y ago
    Is RocketLab able to 3D print larger rockets?
iamcreasy 6y ago
If you look back at how they learned about landing Falcon 9 first stage - they failed many times before succeeding : https://www.youtube.com/watch?v=bvim4rsNHkQ https://www.youtube.com/watch?v=bvim4rsNHkQ
- blackrock 6y ago
  Always fascinating to watch. Thanks for the link.
baq 6y ago
SN8 was more like 99% successful. it only failed because the fuel mix became a bit too engine-rich. SN9 supposedly has a fix for that. the biggest risk was the reverse belly flop and that went flawless to everyone's surprise. to quote musk, the crater is in the right place, and it didn't even properly explode anyway - the nose cone was more or less intact :) if the fuel pressure issue really is fixed and SN9 lands on the pad, it'll be a mark of a new age of space industry - and not that long after the previous one set by the same company! the most recent NRO mission flew on a booster used four times previously; fifteen years ago you'd be laughed out of the room for just suggesting the possibility of launching a national security payload on a used rocket.
saberdancer 6y ago
Depending on the g-load, they may make a less radical flip when handling passengers. Once they figure it out, it's just a matter or refining the parameters.

andrewflnr 6y ago

Gs come from acceleration, either straight line or centripetal. I don't think there is enough control authority in starship's fins to create much centripetal acceleration the way a fighter jet's wings can. If the rocket is capable of it, it would do the same whether it was belly-flopping or dropping straight down the whole way. Any passengers will certainly get an inner-ear workout, but I can't imagine how the flip, more or less around the rocket's own axis, could contribute significantly to G-loading.

christophilus 6y ago
You’re still spinning violently and then snapping to a stop. I wonder if the payload could be designed to counter that in some way? If it was suspended in a liquid, that might work, but that’s unrealistic.

juanbyrge 6y ago

I don’t mean to trivialize what SpaceX is accomplishing, but maybe we are overestimating the degree of difficulty of building rockets in the 21st century, given the advances in technology over the past few decades? With the immense improvement in compute power, materials, accelerometers, welding techniques, etc.. since the 60s, maybe SpaceX was the first to recognize that building rockets is not as hard as it used to be?

nickik 6y ago
Well, we actually have a large amount of companies trying to do it. Like 40-60 different companies. Not to mention government projects. Of all of those, only RocketLab has managed to do it, and their rocket is basically as tiny as you can build a orbital rocket. SpaceX did an orbital rocket bigger then RocketLab in 2008. RocketLab doesn't yet have real competition, despite many billions invested. SpaceX at the same time went from the tiny Falcon 1 to a gigantic Starship program more ambitious then Saturn V and Apollo. I think we do our self a dissevers by just saying 'well, we have computers now so its easy'. Given how many people have tried and how many have failed or taken many, many years longer then they thought, it is clearly not easy at all. And mass producing them reliably is even harder. SpaceX and Elon Musk are clearly special and unique. Something we have never seen before.
- christophilus 6y ago
  ULA is doing it, and seems to be a commercial success. I’m genuinely curious why ULA doesn’t get more publicity.
  - nickik 6y ago
    ULA is not new, its basically Boeing and Lockheed Martin getting together to form a monopoly. The rockets themselves have a lot of legacy going back 60 years. These rockets were developed for the US government and ULA itself has never created its own rocket. I also didn't talk about China or Indian launch who are also doing it.
- blackrock 6y ago
  Is RocketLab able to 3D print larger rockets?

iamcreasy 6y ago

If you look back at how they learned about landing Falcon 9 first stage - they failed many times before succeeding : https://www.youtube.com/watch?v=bvim4rsNHkQ https://www.youtube.com/watch?v=bvim4rsNHkQ

blackrock 6y ago
Always fascinating to watch. Thanks for the link.

baq 6y ago

SN8 was more like 99% successful. it only failed because the fuel mix became a bit too engine-rich. SN9 supposedly has a fix for that. the biggest risk was the reverse belly flop and that went flawless to everyone's surprise. to quote musk, the crater is in the right place, and it didn't even properly explode anyway - the nose cone was more or less intact :) if the fuel pressure issue really is fixed and SN9 lands on the pad, it'll be a mark of a new age of space industry - and not that long after the previous one set by the same company! the most recent NRO mission flew on a booster used four times previously; fifteen years ago you'd be laughed out of the room for just suggesting the possibility of launching a national security payload on a used rocket.

saberdancer 6y ago

Depending on the g-load, they may make a less radical flip when handling passengers. Once they figure it out, it's just a matter or refining the parameters.