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NASA SLS/Orion/Payloads


_Augustus_

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1 minute ago, sh1pman said:

I think you did, significantly more than once...:)

So the reason why the Gateway will be at NRHO is because Orion can't visit any lower orbit. It is this way, because Orion's ESM is a copy of ATV service module and has 2 times less fuel than Apollo CSM. NASA decided to keep it small because SLS Block 1 can't send more than 26t to TLI... Did I get everything right?

It could go to L1 or L2 but they have chosen the NRHO for reasons other than Delta V. In KSP DeltaV is always the priority to consider but this isn't necessarily true in real spaceflight.

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3 minutes ago, Canopus said:

"A Delta V capability of 5 km/s covers the round trip between the Gateway and the surface."

Then the quoted dry mass is wrong, or the RL-10s are better than any ever flown.

The Isp needs to be 493s for 62 tonnes wet, 22 dry to have 5000 m/s dv.

Just now, Canopus said:

It could go to L1 or L2 but they have chosen the NRHO for reasons other than Delta V. In KSP DeltaV is always the priority to consider but this isn't necessarily true in real spaceflight.

They chose the orbit they did for Gateway because Orion can get there and back.

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1 minute ago, tater said:

Then the quoted dry mass is wrong, or the RL-10s are better than any ever flown.

The Isp needs to be 493s for 62 tonnes wet, 22 dry to have 5000 m/s dv.

They chose the orbit they did for Gateway because Orion can get there and back.

Orion can get to Lunar L1 or L2, which seems to be better suited for a roundtrip to the Lunar surface at first sight But as i said may not actually be the better option.

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Alternately, the thing could have the best RL-10s, and the wet mass could be 66 tonnes.

Just now, Canopus said:

Orion can get to Lunar L1 or L2, which seems to be better suited for a roundtrip to the Lunar surface at first sight But as i said may not actually be the better option.

I'm not seeing how it can have 5 km/s of dv given the mass, assuming it is not staged.

Given the sort of stuff nanoracks is working on, it seems like a better option would be to have the decent props in their own tank, and that tank is then left on the surface, reducing the ascent dry mass. Refilling would then be via topping the ascent tanks, and simply replacing the decent tank (common bulkhead tank). That's assuming you want to turn spent tanks into habitable volume at some point.

A lander based on ACES makes way more sense, IMO.

Wonder if some % of that dry mass is not to be reused, but left on the surface as cargo/experiments/etc? They can get to 5000 m/s by buying just a few hundred m/s (it's cheaper to lose mass than add props).

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56 minutes ago, Canopus said:

They call the engines "Rl-10 derivatives with deep throttling capabilities" so they might just be optimistic about new manufacturing capabilities.

Yeah, but 493 is well outside the 465 they can get now (which is incredibly good, it’s a great engine).

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Just now, tater said:

Yeah, but 493 is well outside the 465 they can get now (which is incredibly good, it’s a great engine).

I'm sure they know what they are doing, might just be that the numbers for the mass in the paper are wrong.

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44 minutes ago, Canopus said:

I'm sure they know what they are doing, might just be that the numbers for the mass in the paper are wrong.

No doubt., so the lander can just make a RT, presumably. I saw something that did the math and basically a LEO-lunar surface mission need an extra 1.6 km/s if you go via the Gateway, vs direct from LEO.

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1 hour ago, tater said:

No doubt., so the lander can just make a RT, presumably. I saw something that did the math and basically a LEO-lunar surface mission need an extra 1.6 km/s if you go via the Gateway, vs direct from LEO.

It should’ve been called the Roadblock instead of the Gateway then. Because it increases the difficulty of Moon missions instead of simplifying them.

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1 hour ago, sh1pman said:
Extremely Unlikely Stage fits better at this point.

WAsn't it already delayed to 2023?  So now EUS isn't until 2024 or 2025?  SpaceX could make 2-5 BFRs in the time it takes NASA to make just one EUS.

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Block I has literally three payloads:

  • EM-1
  • EM-2
  • Europa Clipper

You can't comanifest DSG modules on Block I with Orion, which would mean they'd require their own propulsion, in which case why not fly them on commercial LVs?

I guess CAESAR, if selected, could fly on Block I and arrive at 67P faster, but that might exceed the mission's budget.

An ice giant mission or Cassini follow up could work, but that's not in development.

BA-2100 doesn't exist.

 

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13 hours ago, DAL59 said:

WAsn't it already delayed to 2023?  So now EUS isn't until 2024 or 2025?  SpaceX could make 2-5 BFRs in the time it takes NASA to make just one EUS.

I'd place the blame on Boeing and Congress. Boeing has pretty much completely screwed every aspect of SLS they could and Congress just doesn't care.

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11 hours ago, Bill Phil said:

I'd place the blame on Boeing and Congress. Boeing has pretty much completely screwed every aspect of SLS they could and Congress just doesn't care.

Boeing needs to be investigated for... a lot of things. Between their failures on SLS, their failures on Starliner which they try to cover up, falsely claiming they alone build and own SLS, and the libel against SpaceX, I wouldn't be surprised if they've broken some laws at this point.

Unfortunately, this is Boeing we're talking about, and the US government is super corrupt - were either of those not the case, we probably wouldn't have an SLS rocket to criticize.......

Edited by _Augustus_
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2 hours ago, _Augustus_ said:

Boeing needs to be investigated for... a lot of things. Between their failures on SLS, their failures on Starliner which they try to cover up, falsely claiming they alone build and own SLS, and the libel against SpaceX, I wouldn't be surprised if they've broken some laws at this point.

Plus the whole "forcing NASA to delay CC because they don't want SpaceX to beat them" thing.

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13 minutes ago, DAL59 said:

Plus the whole "forcing NASA to delay CC because they don't want SpaceX to beat them" thing.

That's not really a thing. The NASA Commercial Crew schedule they released still has SpaceX flying both the test and crew missions ahead of Boeing.

The editorials are certainly shady, but I'd not draw any hard connections given the current public information we have regarding schedule. ISS docking opportunities are troublesome, and the Russians have dropped a crewman until they fly their new module, so ISS will be shorthanded to a total of 5 crew for the foreseeable future.

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Wow. That report contains this:

NASA is paying AJR $127,000,000 EACH to refurb the SSMEs that they will then throw into the ocean.

So the 4 engines alone cost over a half a billion dollars. Every. Single. Launch.

 

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