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[New] Space Launch System / Orion Discussion Thread


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10 minutes ago, jadebenn said:

Dragon is a pretty terrible cargo carrier for Lunar COTS, though. There's no way it would be able to bring any downmass back to Earth from NRHO, so the Dragon heatshield is useless mass and reuse would be impossible.

I wasn't thinking return to Earth for Dragon LCOTS. If it could do that, then we could also just launch crew on Dragon instead of Orion. I doubt that the gateway will need downmass that Orion can't offer for a while.

Without the heatshield, parachutes, and superdracos, you would have an easier time getting there too.

(Tangent about how much cargo D2 could get to NRHO)

From what I can find, going from TLI to NRHO is around 450m/s (FH would get D2 to TLI just fine I think). I am having a very hard time finding a proper dry mass for dragon 2 and a proper fuel load... I am finding everything from 6.5 tons and 1.3 tons to 9.5 tons and 2.2 tons... I am going to go with the numbers on the environmental assessment for landing. https://www.faa.gov/about/office_org/headquarters_offices/ast/environmental/nepa_docs/review/launch/media/draft-ea_spacex-dragon-gulf-landing.pdf

Dry mass 7.7 tons, fuel mass up to 2.2 tons. Draco ISP of 300s. Delta V is about 740m/s. However, we have not factored in cargo. If we assume 100m/s for docking, undocking, and de-orbit plus safety margin, we need a total of 550. Running the numbers gives us, unfortunately, only 3 tons of cargo, half of what dragon is rated for. However, the heat shield, superdracos, and parachutes aren't light, so once we remove those we get maybe 3.5 tons or 4 if we're lucky. For comparison normal enhanced Cygnus can also carry 3.5-4 tons.

(End tangent)

And that's off the shelf besides the removal of entry equipment and addition of comms/other lunar equipment.

I can't find any numbers on Cygnus but it's almost certain that it has less Delta-V than Dragon 2, as it wasn't designed with launch abort or propulsive landing in mind. It would take a lot more effort to modify Cygnus to be able to reach Gateway than it would Dragon 2.

Dragon 2 can also dock off the shelf, whereas Cygnus berths, and there won't be a robot arm on gateway for a while. This can be changed fairly easily compared to other things, but it's still a change.

If we're only thinking about minimal modifications to get going quickly with a low dev cost, Dragon 2 seems like a really good choice.

However... They already have to get a Cygnus Derivative to the gateway for the MHM/HALO module, so if they're already doing the development on getting something Cygnus-y to have the fuel, comms, docking, etc. to get to gateway, it would mean that they could do the same thing to a Cygnus if they play their cards right.

Which means that in this case, Cygnus is a really good choice because they already have to do big modifications to something closely related, including comms, which would still have to be modified on D2.

I wonder if they are considering just one provider or two... If two, then D2/Cygnus variants seem like good choices (one can get there almost off the shelf, one has the modifications already paid for). However, I doubt that Gateway will need two resupply carriers... I can't imagine needing more than one per crew, and that's one a year max.

 

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9 minutes ago, Ultimate Steve said:

However... They already have to get a Cygnus Derivative to the gateway for the MHM/HALO module, so if they're already doing the development on getting something Cygnus-y to have the fuel, comms, docking, etc. to get to gateway, it would mean that they could do the same thing to a Cygnus if they play their cards right.

Which means that in this case, Cygnus is a really good choice because they already have to do big modifications to something closely related, including comms, which would still have to be modified on D2.

I'd guarantee you that's Orbital's NGIS's game-plan.

They'll already have to replace the berthing mechanism with an NDS port for the MHM, so that's something they'd know how to do with a Lunar Cygnus. They'd also have equipment designed to withstand the NRHO environment, and experience using it. The main differences from the MHM would presumably be the lack of extra docking ports, and less-beefy life support systems.

Edited by jadebenn
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1 hour ago, jadebenn said:

Dragon is a pretty terrible cargo carrier for Lunar COTS, though. There's no way it would be able to bring any downmass back to Earth from NRHO, so the Dragon heatshield is useless mass and reuse would be impossible.

I honestly wouldn't be surprised if they instead form a partnership with NGIS and have a Lunar Cygnus launch on FH instead.

Cygnus has no downmass from anywhere at all.

Dragon would be fine for a lunar version of COTS, as was said, delete chutes, etc, it merely needs to be disposed of (ditto Cygnus), not sent home (which would require a SM, anyway).

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1 hour ago, jadebenn said:

It could be made to work. But since it's going to be disposed of and can't do downmass from NRHO, I find it hard to see how Cygnus wouldn't be the superior option here.

What Atlas V gets it to TLI? a 541 or 551?

Yeah, probably best, but expensive, the launch alone is about 150 M$ (vs 90 M$ for Dragon). Or they could fly Cygnus on FH, lol.

It might be interesting to see if the cargo version of Crew Dragon could return from NRHO, however, then SpaceX could test a direct entry with that vehicle. If it works, they would have some downmass. Not that there is any reason to have ay, there's not really much of interest to do at Gateway.

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9 hours ago, Ultimate Steve said:

 

Idk about reusability though. If you gave dragon 2 an actual service module, then it might actually be able to take crew to and from gateway on an expendable Falcon heavy, but you would have to probably modify the heat shield, comms, and life support. And also get fh man rated.

Even if you could get a D2 to NRHO with crew, it would have too little volume, which is why we need Orion.

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2 hours ago, Barzon Kerman said:

Even if you could get a D2 to NRHO with crew, it would have too little volume, which is why we need Orion.

Include CST-100, as well. The difference in usable volume between the 3 is in fact very small. The 2 Commercial Crew vehicles have very sparse interiors, with a lot of room, Orion has a much larger pressurized volume, but the usual volume is only about half the pressurized volume (interior is filled with equipment).

 

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31 minutes ago, Barzon Kerman said:

yes, but that equipment is needed. If it wasnt, it wouldn't be there.

It's a matter of where the equipment actually is (inside vs outside the pressure vessel) as well. The duration issue is largely a function of the service module, all the commercial crew vehicles are larger than Apollo in volume (substantially). If CST-100 or Dragon were given proper SMs, the only issue would be reentry. I realize you were replying to a post about using Commercial Crew as crew vehicles, I was only discussing using cargo Dragon 2 as a resupply ship. SpaceX has said that Dragon could do a direct entry from the Moon, though, so it might be interesting to see them try that (say downmass cargo, uncrewed).

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On 8/22/2019 at 12:13 PM, wumpus said:

Of all the innovations that have come out of SpaceX, why did NASA/Boeing have to pick up "Elon time"?

What innovations? Unless over-promising and under-delivering massively is an innovation.  

I don't think SpaceX has any patents. They stand on the shoulders of many other great innovators.

The landing rockets shtick was done decades ago. If it saves any real money is unknown.

 

 

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3 hours ago, Kerbal7 said:

What innovations? Unless over-promising and under-delivering massively is an innovation.  

I don't think SpaceX has any patents. They stand on the shoulders of many other great innovators.

The landing rockets shtick was done decades ago. If it saves any real money is unknown.

Absolutely, 100% agree, SpaceX is so insignificant, unoriginal and derivative that I’m really quite baffled as to why would someone even mention it here in the thread dedicated to such an innovative marvel of engineering which is SLS.

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Apart from the fact that there are sound business reasons not to file patents, most patented things are evolutionary rather than revolutionary.

For every patent that covered a game-changing invention, there'll be many more covering small improvements to it, and many more still covering variations on that invention that are just different enough to avoid the original patent. Different doesn't even imply better - the older a technical field is, the more baroque the patents get, simply because most of the truly innovative solutions to a problem have already been patented.

Number of patents is really a very crude measure of innovation, although its a very easily measured one, which is why people like it. And that's without getting into a debate over the term 'innovation' which is one of those all-things-to-all-people words. 

TL: DR, I wouldn't regard SpaceX's lack of patents as any sort of commentary on their innovation or lack of innovation.

Source: 20 odd years working with patents in various capacities.

 

Edit. The same comments apply to any company. I’m not singling SpaceX out for any special treatment here.

Edited by KSK
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I can think of three main reasons for patents:

1) you don't want people to use your idea

2) you do want people to use your idea, but you want them to pay for it

3) you want to make sure that you can use your idea without somebody else claiming you stole it from them

 

If you have reason to think nobody else can use your idea anyway, there's no real point to patenting.

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Some posts have been removed.

While we understand there is a lot of crossover between the two topics, and some cross topic talk is to be expected, let's stay focused on NASA/SLS.   If there is some mention of SpaceX, that's fine, it'll happen, as they work closely together, but let's not drag the discussion solely about SpaceX, they have their own thread. 

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7 hours ago, mikegarrison said:

I can think of three main reasons for patents:

1) you don't want people to use your idea

2) you do want people to use your idea, but you want them to pay for it

3) you want to make sure that you can use your idea without somebody else claiming you stole it from them

If you have reason to think nobody else can use your idea anyway, there's no real point to patenting.

Broadly speaking, yes. There are other considerations too that feed into your summary but this is an SLS thread not a patent law / IP management thread!

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14 hours ago, mikegarrison said:

I can think of three main reasons for patents:

1) you don't want people to use your idea

2) you do want people to use your idea, but you want them to pay for it

3) you want to make sure that you can use your idea without somebody else claiming you stole it from them

 

If you have reason to think nobody else can use your idea anyway, there's no real point to patenting.

That the US patent office advertises using "shield patents" for reason #3 tells you quite a bit about how broken the US patent (and any similar system) is.  Also it's been like this at least through a couple Bush administrations and two Democratic administrations as well, so much of the political machinery holding it together is bipartisan (I'm guessing anyone who can afford effective lobbyists can afford enough patent lawyers to usually get an edge against the competition).

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Not at all, although, as with most things when you’re talking about patents, the devil is in the details. In this case, if you’re an established company or a startup looking for investment, it can make sense.

For an established company, filing a patent is relatively cheap and it gives you an indisputable record that you had the idea on a given date. If somebody comes after you for stealing their idea, you’ve got a concrete date that you can rely on, which can be lot easier and cheaper than proving that same date from your own internal records.

Discovery (being compelled to produce documents as a prelude to litigation) is no fun at all, and it sure as hell ain’t cheap, especially for US litigation. Been there, done that, was responsible for collating everything. It’s bad enough if you’re litigating over patents (with the aforementioned concrete dates to rely on) - I don’t want to imagine how it goes for trade secret litigation.

For a startup company - file the patent. Either that or be prepared to have an absolutely cast iron strategic reason for not filing it that you can explain to your potential investors in three bullet points.

if you’re trying to put together a multimillion dollar investment round, that 5K you spent on your patent application will most probably be worth it.

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NASA announced that all of the SRB propellant casings for Artemis 2 have been cast.

Can I just mention how surreal it is how we're already seeing NASA start to talk about the second and third flights of the SLS? I mentioned this on another forum, but it feels like we're finally starting to see the beginnings of the pivot from developmental to operational.

Seeing stuff like this reminds me of diving through very old articles about upcoming Shuttle flights on NSF. And I mean that in a good way!

Edited by jadebenn
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@tater I hope you don't mind me cross-quoting this to the SLS thread, as I realized my reply was probably off-topic for the one you initially posted this in.

4 hours ago, tater said:

It was funded, and required (by that same bill) to fly by the end of 2016.

[...]

https://www.nasa.gov/pdf/510449main_SLS_MPCV_90-day_Report.pdf

That date was recognized by NASA as being impractical at the time, and was pretty much immediately moved to 2017 (which, admittedly, was missed as well).

This is going to sound a bit tinfoil-hattery, but I believe a large part of the SLS's early difficulties (2010-2013) were intentional - created by opponents of the program. The main act of "sabotage" in my mind was letting the clock run out on retaining large portions of the Shuttle workforce, such as the workers at the MAF. They could've been retained, but the administration appeared to deliberately stall until the clock ran out. While 2010 was probably too late to have a completely smooth transition of the Shuttle's industrial base to a Shuttle-derived launch vehicle either way, there was no reason it had to be as rough as it ended up being.

While I have my own suspicions to whom had the administration's ear in pushing these efforts, there's no concrete proof. All I'll say is that I'm pretty sure it wasn't Bolden (he seemed more of a scapegoat than anything else), and I'm pretty sure it wasn't the commercial industry either, though I do think it was done out of a misguided attempt to "help" them.

Anyway, my point is that while politics are often blamed for SLS's problems, there was a concerted effort to try and set SLS up to fail. While this effort failed itself, it still left a lasting (and negative) impact on the project.

Edited by jadebenn
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1 hour ago, jadebenn said:

This is going to sound a bit tinfoil-hattery, but I believe a large part of the SLS's early difficulties (2010-2013) were intentional - created by opponents of the program.

How about created by proponents of harvesting money, instead? All those delays guaranteed additions to the program that were out of the initial scope, and hence deserving of more money. No longer Shuttle SRBs, now dev money for 5 segments. Change the external tank entirely---not Shuttle anymore, needs dev money, tooling, etc. RS-25s no longer used as is, they need to be uprated in thrust, etc, ad nauseum. Every single change increased the budget. Coincidence?

Who gained by the delays? Certainly not "opponents" of SLS, the money was going to be spent regardless of any opposition. The only people who gained by the delays were in fact the proponents.

I'd add that any at NASA centers against SLS knew that nothing in the program would stop it, so delays harm everyone---except those who gain by the delays.

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Considering the person who I suspect, I find that highly unlikely. Besides, Congress -the "porkmasters"-  kept asking NASA why they were delaying and in-general forcing NASA to turn over info and come up with plans instead of allowing them to drag their feet. Plus: how does letting the entire shuttle workforce get laid-off and have to be replaced keep those constituents in jobs and happy? I wouldn't vote for someone who let me lose my job and get replaced by somebody else.

Edited by jadebenn
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