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  On 7/13/2019 at 12:15 AM, tater said:

If they man rate it, then it flies there itself

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They're going to need to man rate Starship at some point. Commercial crew launches to the Gateway is a good opportunity to prove its safety and reliability, before starting selling tickets to Mars.

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  On 7/13/2019 at 1:04 AM, sh1pman said:

They're going to need to man rate Starship at some point. Commercial crew launches to the Gateway is a good opportunity to prove its safety and reliability, before starting selling tickets to Mars.

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That’s a bit like taking a cruise ship to go stay in a yurt, tho, isn’t it? Better to just park the Starship there in orbit for a while. 

Actually, the entire case for the Gateway gets quivery as fresh jello as soon as Starship is operational. Why even bother when NASA could just contract to take astronauts and all their stuff directly to the surface?

Extra surcharge to bring them back. 

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I continue to be amazed at how people are SO SURE that Starship is going to do everything and be everything and work so well, considering that SpaceX has yet to ever successfully launch even a single person into space. It's kind of like if the Wright Brothers were selling people tickets for First Class on 747s in 1902.

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  On 7/13/2019 at 2:24 AM, mikegarrison said:

I continue to be amazed at how people are SO SURE that Starship is going to do everything and be everything and work so well, considering that SpaceX has yet to ever successfully launch even a single person into space. It's kind of like if the Wright Brothers were selling people tickets for First Class on 747s in 1902.

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It’s called being optimistic, yo. :wink: SpaceX has a history of actually delivering on what they promise, if not exactly when they promised. :rolleyes: They still remain in the lead for actually launching people into space from this country again, and they’re way in the lead for the next superheavy launch vehicle, and yes, that includes SLS. 

And Starship rises above even that because if (and when) it works, it will be nothing short of paradigm-changing for the industry. They have the potential to leapfrog right past everyone else who are still struggling to even agree on a design for a lunar lander. Time after time, SpaceX has gone and done the very things that “they” said were impossible, and right now, today, they have flight hardware ready to test with more under construction. So, being optimistic until I see reason to be otherwise is a very rational decision for me. 

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  On 7/13/2019 at 2:24 AM, mikegarrison said:

I continue to be amazed at how people are SO SURE that Starship is going to do everything and be everything and work so well, considering that SpaceX has yet to ever successfully launch even a single person into space. It's kind of like if the Wright Brothers were selling people tickets for First Class on 747s in 1902.

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You are banned from Mars >=|

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  On 7/13/2019 at 3:46 AM, CatastrophicFailure said:

It’s called being optimistic, yo. :wink: SpaceX has a history of actually delivering on what they promise, if not exactly when they promised. :rolleyes: They still remain in the lead for actually launching people into space from this country again, and they’re way in the lead for the next superheavy launch vehicle, and yes, that includes SLS. 

And Starship rises above even that because if (and when) it works, it will be nothing short of paradigm-changing for the industry. They have the potential to leapfrog right past everyone else who are still struggling to even agree on a design for a lunar lander. Time after time, SpaceX has gone and done the very things that “they” said were impossible, and right now, today, they have flight hardware ready to test with more under construction. So, being optimistic until I see reason to be otherwise is a very rational decision for me. 

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To play the devil's advocate, they didn't deliver DragonLab, Falcon Heavy with fuel crossfeed, Falcon 1E, Falcon 5, propulsive landing for Dragon 2, 12m BFR, Carbon Fiber ITS/BFR, second stage reusability, and didn't do Red Dragon or Grey Dragon.

I know that there are good reasons for this, including improved replacements for a lot of those, but the statement that they always deliver what they promise is definitely false.

In the lead for the next SHLV remains to be seen. They have no launch pad, and no trace of the core stage besides the engine, and only a (likely) non orbital spec hopper (missing half of it due to a storm) and two empty hulls for the upper stage. To date they have only delivered six engines when the final vehicle needs around forty.

As far as schedule, SpaceX might come out ahead due to the fact that in this case SpaceX has been moving pretty fast. However, the current target dates for the first full up orbital flight are around the same timeframe, both in 2020. There are doubts as to whether either vehicle will reach that.

SLS is definitely ahead in hardware right now. The core stage, I believe, is mostly assembled. The CM and SM have been mated or are about to be mated. I'm pretty sure the ICPS has been done for a while but I am not sure. I have heard nothing about the boosters as of recent. They also have a launch pad.

I still consider myself an optimist, though. Even if SpaceX can only accomplish what they have done with the Falcon 9 with Starship (just first stage reusability, no second stage reusability, days of turnaround) they still have a game changing rocket, one that can launch 150 tons to LEO for less than 200 million dollars (which is a pessimistic number).

 

 

 

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  On 7/13/2019 at 2:24 AM, mikegarrison said:

I continue to be amazed at how people are SO SURE that Starship is going to do everything and be everything and work so well, considering that SpaceX has yet to ever successfully launch even a single person into space. It's kind of like if the Wright Brothers were selling people tickets for First Class on 747s in 1902.

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I'll believe some of it when they do it (crew, for example), but I think the basic idea of a fully reusable TSTO is either something that happens, or space travel never really progresses.

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  On 7/13/2019 at 2:24 AM, mikegarrison said:

I continue to be amazed at how people are SO SURE that Starship is going to do everything and be everything and work so well, considering that SpaceX has yet to ever successfully launch even a single person into space. It's kind of like if the Wright Brothers were selling people tickets for First Class on 747s in 1902.

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*cough* SLS *cough*

  On 7/13/2019 at 3:46 AM, CatastrophicFailure said:

SpaceX has a history of actually delivering on what they promise, if not exactly when they promised.

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Eeeehh... Kind of. It's not like the upper stage of FH is ever going to land itself. But at least they are trying to change some things in the industry. LinkSpace would probably not be hopping their minirocket if it wasn't for the increasing demand for cheaper thus reusable designs. Same with Callisto and that other chinese Falcon Heavy copy.

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  On 7/13/2019 at 4:39 AM, Wjolcz said:

Kind of. It's not like the upper stage of FH is ever going to land itself.

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They are agile enough to not chase after incremental improvements when a sea change is needed. They are also driven by the (frankly crazy) idea of colonizing Mars.

It's not something I share as a goal, but if they want to make the things to do it... everyone benefits who cares about space exploration.

All the things we could want/need are side benefits of cost-effective mass to LEO.

If a SS launch at 125 mt to LEO (per Musk tweet just above) could be a thing for 50 million a flight, that's $400/kg.

If they can fly 10X more than that on average (whatever that number is), then it's $40/kg. Or simply if SS works, they can simply make them arbitrarily large to get the cost/kg pretty low.

 

https://www.ulalaunch.com/docs/default-source/commercial-space/commercial-lunar-propellant-architecture.pdf?sfvrsn=649113d4_4

In the above ULA study, they call cost of propellant at LEO as $4,000/kg, and at EML1 it's $12,000/kg (3X more at EML1 dragged from Earth). They suggest that ISRU at the Moon could deliver props to LEO for $3000/kg, and to EML1 for just $1000/kg.

What if props can be delivered to LEO for $400, and to EML1 for $1200? ISRU starts looking marginally OK if you are based at EML1, but much worse at LEO than just dragging it up from Earth.

As soon as propellants can be delivered to LEO for under $333/kg, unless the ULA economics are all not optimistic enough, ISRU on the Moon is pointless. That value for SS/SH is around 41.6 million a launch. Musk has said that it seems possible with (massive) reuse to get the cost per launch down to under Falcon 1 price (6M$). He can be off by almost a factor of 7 in that figure and still obviate lunar ISRU as proposed by ULA...

Except that ULA assumes those same costs to get to the Moon in the first place ($36,000/kg), so the infrastructure cost to do the ISRU is vastly higher than it might be with $333/kg to LEO (~$3000/kg for SS to the Moon with the same 9X multiplier). If they can get it to $40, lol, then the cost to the Moon is a few hundred $ a kg.

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  On 7/13/2019 at 4:19 AM, Ultimate Steve said:

they didn't deliver DragonLab, Falcon Heavy with fuel crossfeed, Falcon 1E, Falcon 5, propulsive landing for Dragon 2, 12m BFR, Carbon Fiber ITS/BFR, second stage reusability, and didn't do Red Dragon or Grey Dragon.

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But delivered Tesla.

Edited by kerbiloid
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  On 7/13/2019 at 4:19 AM, Ultimate Steve said:

I know that there are good reasons for this, including improved replacements for a lot of those, but the statement that they always deliver what they promise is definitely false.

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See, now here's part of the problem. I never said "always." :wink: Just about everything you mentioned there didn't happen (or didn't happen yet) because its purpose was absorbed into other projects (No need for colored Dragons when you've got a Starship) or simply rendered unnecessary (composite BFR, crossfeed).

 

  On 7/13/2019 at 4:19 AM, Ultimate Steve said:

As far as schedule, SpaceX might come out ahead due to the fact that in this case SpaceX has been moving pretty fast.

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This is what puts them ahead, in my book. They've gone from nothing to flight-ready prototypes in a fraction of the time it took SLS to go from existing hardware to test-ready prototype. If SLS suffers a major anomaly, it's dead (congress critters notwithstanding). SpaceX can accord to fail (best way to learn) and still forge ahead. I think we'll see a full flight-ready Starship/Superheavy stack on the pad before SLS, easily.

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  On 7/13/2019 at 6:16 AM, tater said:

If they can get it to $40, lol, then the cost to the Moon is a few hundred $ a kg.

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If they get it down that low, I'm launching my own Tesla to Mars. -_-

  On 7/13/2019 at 7:21 AM, Dale Christopher said:

>_<?

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You know, like the vermin who keep getting into your personal stores and just generally making a mess that you can't ever seem to get rid of... :P

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I would be worried to be on an about to be propulsivly landed Starship given that many propulsive landings have failed. 

Given that it was too hard to get the government to agree for a Dragon to land this way how hard would it be to have them approve a much larger vehicle landing like that?

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  On 7/13/2019 at 7:57 AM, Rus-Evo said:

I would be worried to be on an about to be propulsivly landed Starship given that many propulsive landings have failed. 

Given that it was too hard to get the government to agree for a Dragon to land this way how hard would it be to have them approve a much larger vehicle landing like that?

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Well, Texas just cleared the way to do so, and falcon 9s routinely do so on LZs. Precise propulsive landing remains much less tested than landing with parachutes, but as long as you set up an exclusion zone large enough, and have self-destruct explosives onboard, the paperwork should be fine.

On the other hand, manned propulsive landing is a whole different story. A lot, and by a lot I mean a whole freakish ton, of paperwork needs to be done.

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  On 7/13/2019 at 7:57 AM, Rus-Evo said:

Given that it was too hard to get the government to agree for a Dragon to land this way how hard would it be to have them approve a much larger vehicle landing like that?

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They will approve but require a new Starship for every launch, backup chutes, and sea splashing.

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  On 7/13/2019 at 8:58 AM, Xd the great said:

Well, Texas just cleared the way to do so, and falcon 9s routinely do so on LZs. Precise propulsive landing remains much less tested than landing with parachutes, but as long as you set up an exclusion zone large enough, and have self-destruct explosives onboard, the paperwork should be fine.

On the other hand, manned propulsive landing is a whole different story. A lot, and by a lot I mean a whole freakish ton, of paperwork needs to be done.

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Yes, exclusion zone is so large the size of the craft is pretty irelevant as in does not matter much if its an new Shepard or an Starship
You get an high speed crash and an fireball. 

Falcon 9 dogleg from over sea in to LZ is also pretty safe.
After they got the landings rights at start of 2016 it has been one drone ship fail and one ground landing fail, also the FH core fails 

But yes manned is another story. Not sure how FAA comes in here however or if its NASA still think the lack of an abort system is problematic. 

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  On 7/13/2019 at 7:57 AM, Rus-Evo said:

I would be worried to be on an about to be propulsivly landed Starship given that many propulsive landings have failed.

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A very large percentage of the failures were "first time to try X." I.e. there have been relatively few "routine" landings that have failed at the point of actual landing. Yeah, its not a statistically huge number to begin with...

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