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SpaceX Successfully Soft-Landed Booster Rocket in the Atlantic

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Re: SpaceX Successfully Soft-Landed Booster Rocket in the Atlantic

#111

Post by lotsofmangos »

XorNot wrote: post #92
ef4 wrote: post #82

Earlier quoted context omitted.

> you need to strip and re-build the thing That's how politically-designed boondoggles like the shuttle work. It's not inevitable, if you actually spend the engineering effort on reliability and repeatability. If NASA operated an airline, they would probably be tearing down and rebuilding every jet engine after every flight, and a ticket would cost $100,000.

I said this in another thread, but part of the issue is failure intolerance. Sure - for human payloads I'd want to be damn sure my process is good, like, hundreds to thousands of missions deep before I trusted it. But that's totally unnecessary for an unmanned payload! If the cost of launch drops enough, you can fully justify launching 2x the payloads if you expect maybe 1 in 10 failures due to the mode of launch. I…

SpaceX appear to have gone with failure tolerance. Their first stage is practically a raid array.

Re: SpaceX Successfully Soft-Landed Booster Rocket in the Atlantic

#112

Post by avmich »

trhway wrote: post #83
kindredlight wrote: post #26

Earlier quoted context omitted.

All Atlas V first-stage engines (RD-180) are manufactured in Russia. That the second stage engines are made in the US doesn't change the fact that you're dependent on Russian supply. In response to your edits: >but they can't get more flights because of their record The Air Force required 3 successful flights in the exact configuration the Air Force would fly. SpaceX provided the "record" as stipulated by the Air For…

>you're dependent on Russian supply and my understanding that this supply is limited to the what had already been manufactured long time ago. Beside the inventory issues, one can easy imagine Putin saying "bad Americans, no more gas ... err... rocket engines for you"

RD-180 are being manufactured continuously last ~20 years. All new, not manufactured long time ago.

NK-33 - from which AJ-26 are made - aren't manufactured today. It's a question if the manufacturing will restart. There are a few tens of them in US. Orbital Sciences has that question in the middle of their table, or close to it.

Russian-American relationships in space trace back to at least 1975, deep Cold War. We're not at that state of affairs just yet. As somebody mentioned on The Space Review, ISS is a front-runner for Nobel peace prize, so let's not jump the gun too early. It doesn't seem to be too desirable for Putin to close that particular relationship.

Re: SpaceX Successfully Soft-Landed Booster Rocket in the Atlantic

#113

Post by InclinedPlane »

paul_f wrote: post #60

This may be a dumb question, but why are they test landing in the ocean instead of on land? Flight paths preclude it?

Safety and ease. Landing in the ocean they don't have to boost back which saves them fuel (so it's essentially trivial to just add a test onto an existing launch at no significant payload penalty), plus they get to run through most of the flight profile (especially the most important parts) without having any potential of hitting anything on land and with the expectation that the vehicle is going to be destroyed anyway. They have several (at least 4) more flights within the next year with sufficient payload margin to do more of these tests so they can spend time gaining confidence (at almost zero cost to SpaceX) and exploring the boost back trajectory (coming closer to land) before actually attempting a landing.

Re: SpaceX Successfully Soft-Landed Booster Rocket in the Atlantic

#115

Post by rjurney »

001sky wrote: post #100
XorNot wrote: post #92

Earlier quoted context omitted.

I said this in another thread, but part of the issue is failure intolerance. Sure - for human payloads I'd want to be damn sure my process is good, like, hundreds to thousands of missions deep before I trusted it. But that's totally unnecessary for an unmanned payload! If the cost of launch drops enough, you can fully justify launching 2x the payloads if you expect maybe 1 in 10 failures due to the mode of launch. I…

This is true for a sub-set of unmanned payloads. Space-X is great for the sub-set of things that don't require insurance, and don't therefore need to use corner-case mil-spec stuff with the corner case pricing. For others, the cost of losing a $1-2B bird on top of a $100m/cheap rocket is shitty math. Nobody is going to insure the top of it, so ultimately the "waste" is akin to a form of insurance. Everybody knows thi…

You really think SpaceX loads aren't insured? This seems impossible.

Re: SpaceX Successfully Soft-Landed Booster Rocket in the Atlantic

#116

Post by seacious »

mikeash wrote: post #48
physcab wrote: post #15

Earlier quoted context omitted.

ULA uses engines manufactured from many different sources. Some rockets fly with engines manufactured in Russia, and as far as I know these aren't necessarily new engines but re-used from the 60's. But other programs use engines manufactured in the US. Atlas V rockets have engines made by Aerojet Rocketdyne which is based in Sacramento California. http://en.wikipedia.org/wiki/Atlas_V Also to match costs, you have to…

Regarding payloads, it depends on what you're launching. If your satellite is 4 tons, then you can directly compare the price of a Falcon 9 and an Atlas, for example. It doesn't get noticeably cheaper to fly a rocket at less than full payload. Obviously, if you're launching something that exceeds Falcon's maximum payload then it's not an option, but given their campaign, there must be a lot of lighter payloads going…

Musk mentioned GPS satellites as one of the kinds of payloads he wanted to bid for. It looks like they fall well within the capacity of the Falcon 9. See: http://en.wikipedia.org/wiki/GPS_Block_IIF

Re: SpaceX Successfully Soft-Landed Booster Rocket in the Atlantic

#117

Post by HarryHirsch »

rjurney wrote: post #115
001sky wrote: post #100

Earlier quoted context omitted.

This is true for a sub-set of unmanned payloads. Space-X is great for the sub-set of things that don't require insurance, and don't therefore need to use corner-case mil-spec stuff with the corner case pricing. For others, the cost of losing a $1-2B bird on top of a $100m/cheap rocket is shitty math. Nobody is going to insure the top of it, so ultimately the "waste" is akin to a form of insurance. Everybody knows thi…

You really think SpaceX loads aren't insured? This seems impossible.

If you look at previous launches of new designs you will see that the first few flights are invariably not commercial, they carry research spacecraft. These are the qualification flights; until the vehicle has a good track record the satellite operator won't find anyone to insure their bird.

Now the Falcon 9 is an all-new design, and their track record isn't all that shiny - there is a history of missing the target orbit by a fairly significant margin. It's going to be downvoted, but it had to be said.

I wouldn't be surprised if this flight went without insurance.

Re: SpaceX Successfully Soft-Landed Booster Rocket in the Atlantic

#118

Post by XorNot »

001sky wrote: post #100
XorNot wrote: post #92

Earlier quoted context omitted.

I said this in another thread, but part of the issue is failure intolerance. Sure - for human payloads I'd want to be damn sure my process is good, like, hundreds to thousands of missions deep before I trusted it. But that's totally unnecessary for an unmanned payload! If the cost of launch drops enough, you can fully justify launching 2x the payloads if you expect maybe 1 in 10 failures due to the mode of launch. I…

This is true for a sub-set of unmanned payloads. Space-X is great for the sub-set of things that don't require insurance, and don't therefore need to use corner-case mil-spec stuff with the corner case pricing. For others, the cost of losing a $1-2B bird on top of a $100m/cheap rocket is shitty math. Nobody is going to insure the top of it, so ultimately the "waste" is akin to a form of insurance. Everybody knows thi…

Right, but part of the reason we launch hugely expensive satellites is because launching a rocket is hugely expensive.

That calculus changes if your rocket launches start to get cheaper. It changes by a lot if your rocket launches have reasonable but predictable failure modes - which is something you get from volume.

As it is, rocket launches are relatively infrequent and expensive - which means its impossible to figure out the amortization of costs, and its not worth building a 10m satellite if your launch costs 100m (since if you can raise the latter, you can almost certainly get more for a better satellite too).

Re: SpaceX Successfully Soft-Landed Booster Rocket in the Atlantic

#119

Post by 001sky »

XorNot wrote: post #118
001sky wrote: post #100

Earlier quoted context omitted.

This is true for a sub-set of unmanned payloads. Space-X is great for the sub-set of things that don't require insurance, and don't therefore need to use corner-case mil-spec stuff with the corner case pricing. For others, the cost of losing a $1-2B bird on top of a $100m/cheap rocket is shitty math. Nobody is going to insure the top of it, so ultimately the "waste" is akin to a form of insurance. Everybody knows thi…

Right, but part of the reason we launch hugely expensive satellites is because launching a rocket is hugely expensive. That calculus changes if your rocket launches start to get cheaper. It changes by a lot if your rocket launches have reasonable but predictable failure modes - which is something you get from volume. As it is, rocket launches are relatively infrequent and expensive - which means its impossible to fig…

^^^ Yes, this is exactly the 'white space' for Space-X.

Re: SpaceX Successfully Soft-Landed Booster Rocket in the Atlantic

#120

Post by seanjensengrey »

m_mueller wrote: post #89
andrewtbham wrote: post #29

Earlier quoted context omitted.

I watched a senate hearing where Elon Musk squares off with the ULA. It's awesome. One great quote is where the ULA says Space X can't handle the missions. Elon responds. If our rockets are good enough for NASA, they are good enough for the Department of Defense. https://www.youtube.com/watch?v=O_azyt1JhI0

That was an interesting watch, even as a foreigner. The ULA representative did everything he could to defend their contract - a 'good' politicians as it seems. He responded pretty well to Feinstein's chart I have to say - a chart with cost per ton in orbit would have been much more informative and I couldn't deduct from her numbers whether that has actually gone up significantly. Musk's response to Shelby's remark on…

Yeah, that chart is painful. Talking about absolute dollars with no basis is not productive.
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