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4 hours ago, Crimeo said:

I realize engines are obviously more valuable than a few meters of tank, but are not necessarily obviously more valuable than a few meters of tank PLUS the opportunity benefit of not spending money on robot barges, fancy avionics in the first stage, and landing hardware.

The robot barges are reused just like the rocket engines and landing hardware.  So in the long run, I'd expect the savings on the engines and entire LV would far outweigh the original capital costs of landing hardware and a couple of barges.

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Pffft. Even if doing all the reusability stuff only breaks EVEN and doesn't save any money...I'm still in favor of it for the absolute coolness factor of it all. Watching SpaceX learning to land boosters has been the best thing I've seen in rocketry in years.

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The most important thing SpaceX is doing is pioneering the stage recovery technology. If we want to put anything substantial into space, we need reusable boosters. Otherwise, the expense becomes prohibitive, especially considering supplies and transport for manned stations. Things get even worse if we are in Cislunar or near-Earth space - that extra 3.5 km/s severely increases the mass of a launcher departing from Earth. 

SpaceX's rocket landing method is the best we are going to get - we will probably be able to make rockets in space (robotic factories producing fuel, etc) before we have fully reusable, economic space-planes which can carry significant payload. The math just doesn't work without significantly better engines than we can manage with current technology. 

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27 minutes ago, MaxL_1023 said:

The most important thing SpaceX is doing is pioneering the stage recovery technology. If we want to put anything substantial into space, we need reusable boosters. Otherwise, the expense becomes prohibitive, especially considering supplies and transport for manned stations. Things get even worse if we are in Cislunar or near-Earth space - that extra 3.5 km/s severely increases the mass of a launcher departing from Earth. 

SpaceX's rocket landing method is the best we are going to get - we will probably be able to make rockets in space (robotic factories producing fuel, etc) before we have fully reusable, economic space-planes which can carry significant payload. The math just doesn't work without significantly better engines than we can manage with current technology. 

If we want to do anything substantial, we need loads of capital. NASA is able to do great things with what's essentially very little money. We just need more of it. That and proper infrastructure. If we have that in place, then our rockets need only ever go to LEO. But we can use nuclear rockets, either in the form of Project Orion for insane payload with a similar cost (at least in order of magnitude) to the Apollo Program, but with far greater returns. Or we can use Nerva engines, or LANTR. Stage recovery is very useful, of course. But remember, SpaceX aren't the only guys in the game. BO is perfecting the landing before they get their orbital launcher going.

Really what we need is a well oiled machine in the form of infrastructure.

Rocket takes payload to LEO. Space tug grabs payload and rendezvous with a "spaceport." A space cargo ship, or just some sort of transfer vehicle, then takes the payload to its destination. That'd be a good way to start out. Then having "ports" in various locations of interest, namely LEO and GEO, would benefit us greatly.

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I think the era of nation-states spending significant chunks of their GDP on space programs because politics has come to an end. We are now in the era of billionaires spending significant chunks of their own wealth on space programs because AWESOME!. Hopefully this will last long enough to bridge the gap to ordinary people spending ordinary sums to finance space programs, because ________(?). I really believe if they can just make it cheap it enough, other people will suddenly find reasons to go there.*

*I have zero empirical evidence to actually support this.

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2 hours ago, Bill Phil said:

If we want to do anything substantial, we need loads of capital. NASA is able to do great things with what's essentially very little money. We just need more of it. That and proper infrastructure. If we have that in place, then our rockets need only ever go to LEO. But we can use nuclear rockets, either in the form of Project Orion for insane payload with a similar cost (at least in order of magnitude) to the Apollo Program, but with far greater returns. Or we can use Nerva engines, or LANTR. Stage recovery is very useful, of course. But remember, SpaceX aren't the only guys in the game. BO is perfecting the landing before they get their orbital launcher going.

Really what we need is a well oiled machine in the form of infrastructure.

Rocket takes payload to LEO. Space tug grabs payload and rendezvous with a "spaceport." A space cargo ship, or just some sort of transfer vehicle, then takes the payload to its destination. That'd be a good way to start out. Then having "ports" in various locations of interest, namely LEO and GEO, would benefit us greatly.

So basically what we need is the Space Transportation System.

 

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18 hours ago, tater said:

The problem with reuse and cost is that they have a staff that needs to be working, and if they are making rockets, then need to launch them. All of them, plus the reused ones. Otherwise they end up with a hanger full of rockets. It comes down to launch cadence as always. Jury is out.

SpaceX has an backlog now and want to expand so they need more launches, they can always fire people if needed too but look like they will rater be expanding. 
In short the costs is 1) yearly fixed cost even if not launching 2) cost of doing the launch including integration 3) cost of the rocket itself. 
3) will be replaced with an far smaller cost of verifying the rocket after returning a bit more for the barge landing. Non of the other are affected. 
 

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5 hours ago, CatastrophicFailure said:

I think the era of nation-states spending significant chunks of their GDP on space programs because politics has come to an end. We are now in the era of billionaires spending significant chunks of their own wealth on space programs because AWESOME!. Hopefully this will last long enough to bridge the gap to ordinary people spending ordinary sums to finance space programs, because ________(?). I really believe if they can just make it cheap it enough, other people will suddenly find reasons to go there.*

*I have zero empirical evidence to actually support this.

I think that next step would be that billionaires would invest billions as owners of space mining companies because they want to get profit. But it takes several decades and uncountable billions before technology is at that point. Currently there are couple of interested billionaires and their projects are more hobby than severe business investments. I am sure that for example Musk and Bezos would get more profit for their capital if they would invest it to another businesses and that they know it but choose awesomeness.

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15 hours ago, Crimeo said:

I realize engines are obviously more valuable than a few meters of tank, but are not necessarily obviously more valuable than a few meters of tank PLUS the opportunity benefit of not spending money on robot barges, fancy avionics in the first stage, and landing hardware.

If I remember correctly, there was some announcement that SpaceX has already invested couple of billions to develop reusing. If they save couple of tens of millions per launch, they can pay it back during about 100 launches. Maybe in 5 years. And they can use technology in their coming larger rockets and develop it further. It is not necessarily bad business, if there will not be unforeseeable severe problems. They have full order book and it takes several years before competitors get their rockets to regular flights and force them to reduce prices.

I am sure that coming decade or two will show if reusing will be real breakthrough. I would say that at this point it looks very promising technology, but of course nobody can show it exactly.

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1 hour ago, Hannu2 said:

If I remember correctly, there was some announcement that SpaceX has already invested couple of billions to develop reusing. If they save couple of tens of millions per launch, they can pay it back during about 100 launches. Maybe in 5 years. And they can use technology in their coming larger rockets and develop it further. It is not necessarily bad business, if there will not be unforeseeable severe problems. They have full order book and it takes several years before competitors get their rockets to regular flights and force them to reduce prices.

I am sure that coming decade or two will show if reusing will be real breakthrough. I would say that at this point it looks very promising technology, but of course nobody can show it exactly.

SpaceX reuse program was pretty cheap in hardware. They had the grasshopper test platform for landing who was an cheap version of an falcon 9 lower stage with fewer engines. 
Then they added the upper stage flight control system to lower stage for testing turnaround and decent, this was done on standard flights, then add legs and start to try to land.
Crash 5-6 times, learn by mistakes and it works.
I do not know how much they used to develop the technology but it the kerbal way they developed it make it look pretty cheap compared to the other stuff they do like falcon 9, the dragon pod or the merlin engine. 
its far more expensive to develop something if you want to be 99% sure it works the first time than if you can tinker and test. 
Now the Falcon 9 development towards full trust was needed for reuse but something who makes sense anyway. 
Now they can probably write off all the crashed stages as expenses during the testing program to save tax. 

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1 hour ago, magnemoe said:

SpaceX reuse program was pretty cheap in hardware. 

But they went through  falcon9 1.0 (could launch into orbit, no reuse), falcon 1.1 (60% more mass), full thrust, block 5.  While 1.1 managed to land, you can be pretty sure that all (Falcon) R&D after 1.0 made orbit was for recovery.  That's a huge amount of Spacex's expenses (although, as you noted they never had to throw away a ~$100,000,000 rocket just to test the lander).

10 hours ago, Brotoro said:

Pffft. Even if doing all the reusability stuff only breaks EVEN and doesn't save any money...I'm still in favor of it for the absolute coolness factor of it all. Watching SpaceX learning to land boosters has been the best thing I've seen in rocketry in years.

I suspect that this has a lot to do with the difference in hours worked by Spacex people vs. NASA people.  This might be some of the cheapest R&D (that doesn't involve specifically donated R&D) around.

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14 hours ago, Soda Popinski said:

The robot barges are reused just like the rocket engines and landing hardware.  So in the long run, I'd expect the savings on the engines and entire LV would far outweigh the original capital costs of landing hardware and a couple of barges.

The barges represent very little capital investment anyway; they're leased ones with some bolt-on SpaceX upgrades, not custom-built.

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21 minutes ago, wumpus said:

But they went through  falcon9 1.0 (could launch into orbit, no reuse), falcon 1.1 (60% more mass), full thrust, block 5.  While 1.1 managed to land, you can be pretty sure that all (Falcon) R&D after 1.0 made orbit was for recovery.  That's a huge amount of Spacex's expenses (although, as you noted they never had to throw away a ~$100,000,000 rocket just to test the lander).

I'd wager that a majority of post-v.10 R&D was recovery-oriented, but not all of it. Even the fully-expendable Falcon 9 FT is a far, far more capable launch vehicle than v1.0 was. Remember that v1.0 couldn't even launch satellites; it had no clamshell fairing, no octaweb, nothing. Falcon 9 FT can send more to GTO than Falcon 9 v1.0 ever sent to LEO.

Edited by sevenperforce
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2 hours ago, wumpus said:

But they went through  falcon9 1.0 (could launch into orbit, no reuse), falcon 1.1 (60% more mass), full thrust, block 5.  While 1.1 managed to land, you can be pretty sure that all (Falcon) R&D after 1.0 made orbit was for recovery.  That's a huge amount of Spacex's expenses (although, as you noted they never had to throw away a ~$100,000,000 rocket just to test the lander).

I think most of the R&D went to adding launch capacity to the rockets, after that it was mostly trial and error using fully-paid-for-and-expended first stages as testing platforms.

Sure they added a probe-core and extendable fins, but the legs were not added until they were confident that they could land them exactly where they wanted them.  

It is pretty neat when you can have your clients pay for your on-going R&D and still be the cheapest option available...

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20 hours ago, Scotius said:

4000+ sats in LEO.

4000 is for cowards.

True guys launch 12000.

https://translate.google.ru/translate?sl=ru&tl=en&js=y&prev=_t&hl=ru&ie=UTF-8&u=http%3A%2F%2Fwww.interfax.ru%2Fworld%2F561164&edit-text=

(Link from the article:

https://cdn.arstechnica.net/wp-content/uploads/2017/05/Legal-Narrative.pdf

Edited by kerbiloid
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5 hours ago, Terwin said:

I think most of the R&D went to adding launch capacity to the rockets, after that it was mostly trial and error using fully-paid-for-and-expended first stages as testing platforms.

Sure they added a probe-core and extendable fins, but the legs were not added until they were confident that they could land them exactly where they wanted them.  

It is pretty neat when you can have your clients pay for your on-going R&D and still be the cheapest option available...

At least they don't reuse customer satellites by putting them in orbit around the Moon after getting them to GSO, Looking at you KSP players. 

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16 hours ago, magnemoe said:

At least they don't reuse customer satellites by putting them in orbit around the Moon after getting them to GSO, Looking at you KSP players. 

At least one GSO satellite has been looped around the Moon after getting into the wrong position after the initial burn.  Read about it roughly before 2000.  Not sure how much that limited its lifespan by using up so much stationkeeping fuel.

21 hours ago, Terwin said:

I think most of the R&D went to adding launch capacity to the rockets, after that it was mostly trial and error using fully-paid-for-and-expended first stages as testing platforms.

Sure they added a probe-core and extendable fins, but the legs were not added until they were confident that they could land them exactly where they wanted them.  

It is pretty neat when you can have your clients pay for your on-going R&D and still be the cheapest option available...

I can't help but think it would be a lot cheaper (R&D wise) to simply add solid boosters.  Especially if 1.0 was designed with becoming falcon heavy in mind (of course considering how cash strapped they were when designing it, my guess was that heavy came along with 1.1 (I had no idea that 1.0 was essentially limited to launching dragon 1.0).

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4 hours ago, wumpus said:

At least one GSO satellite has been looped around the Moon after getting into the wrong position after the initial burn.  Read about it roughly before 2000.  Not sure how much that limited its lifespan by using up so much stationkeeping fuel.

Remember that satellite, however it was an operation to get it into its orbit, it was not to put an earth observatory satellite in orbit around the Moon as you wanted to do science around moon, again this is something most KSP players has done :)

 

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1 hour ago, magnemoe said:

Remember that satellite, however it was an operation to get it into its orbit, it was not to put an earth observatory satellite in orbit around the Moon as you wanted to do science around moon, again this is something most KSP players has done :)

 

NASA did this as well https://en.m.wikipedia.org/wiki/THEMIS

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1 hour ago, magnemoe said:

Remember that satellite, however it was an operation to get it into its orbit, it was not to put an earth observatory satellite in orbit around the Moon as you wanted to do science around moon, again this is something most KSP players has done :)

No, he was right; https://en.wikipedia.org/wiki/PAS-22

In theory you could save a bunch of fuel for most GSO sats by doing something similar, but thermal issues mean it's considered too much of a risk.

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