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Artemis Discussion Thread


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29 minutes ago, sevenperforce said:

They had dropped the drop-tank design due to the number of safety-critical separation events. They were doing for methalox and they wanted to develop the engine in-house. But apparently they hadn't even decided yet whether to use pressure-feeding or a pump-fed design.

No wonder they got rejected if they didn't even have a concrete engine design.

Sigh. Well I guess it can't be helped. I suppose paper rocket is just a rocket on paper, and actual rocket debris are used to be an actual rocket.

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2 minutes ago, kerbiloid said:

Depends on sfx in the video.

Their youtube channel doesn't really have any good animation. If someone made their lander for a KSP mod, any content from KSP is better.

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1 hour ago, tater said:

NASA should get their money back on that proposal.

How is that a good faith proposal?

Well in a lot of contract competition you're allowed to take what you need, and everyone is allowed in as long as they pass the requirement for that stage. In this case it's more of a grant however so it works the same but with money handed over.

Will say though that these guys didn't really focus on rockets... maybe that's where they shot their foot since this would be their first proper rocket-based stuff (and taking in SNC doesn't improve the image much either as their significant rocket-based work so far is the SpaceShipTwo solid-based boost rocket and that was done in 2014). Interestingly their parent company included what used to be a division of Lockheed Martin.

Still kinda hoping if anyone else is interested to handle purely orbit-surface vehicles for Moon or Mars... yes you technically can always throw an SS at it but making access easier would be a nice thing to have, unless side-landing SS is a thing...

Edited by YNM
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21 minutes ago, tater said:

NASA should get their money back on that proposal.

How is that a good faith proposal?

I'm sorta shocked at how bad that is.

"While Dynetics realizes and has been actively addressing [the negative mass] issue during its base period performance, its proposal does not provide sufficient details regarding its plan for executing on and achieving significant mass opportunities, especially when in the same breath, the proposal also identifies material additional mass threats."

There's always this image from inside their mockup, though....

index.php?PHPSESSID=clsa0k7hmkhjlmii6mm9tqm1re&action=dlattach;topic=50843.0;attach=2026998;image

If this image is to be believed, then it looks like they were considering methalox electric-pump-fed engines. 3 bar in the tanks. 28kW batteries. Thrust is roughly proportional to turbopump power so we're looking at ~6 kN engines, about a third of the thrust of the Apollo LM ascent engine.

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13 minutes ago, sevenperforce said:

If this image is to be believed, then it looks like they were considering methalox electric-pump-fed engines. 3 bar in the tanks. 28kW batteries. Thrust is roughly proportional to turbopump power so we're looking at ~6 kN engines, about a third of the thrust of the Apollo LM ascent engine.

So 48kN total. Apollo descent engine is 45kN.

https://en.wikipedia.org/wiki/Descent_propulsion_system

 

Ascent engine  is ~1/3

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36 minutes ago, sevenperforce said:

That’s fine, methalox has much more specific energy than hypergols 

We never got mass data on the thing, however.

The difference in even "Kremlinology" WRT the other 2 and SpaceX is pretty funny. We literally have picturs of the bills of lading for the steel they are using, and can work out the mass that way.

NT and Dynetics? <shrug>

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  • 1 month later...
  • 3 weeks later...
Quote

Since 2007, NASA has spent about $420.1 million on spacesuit development. Going forward, the Agency
plans to invest approximately $625.2 million more, bringing the total spent on design, testing,
qualification, an ISS Demo suit, two flight-ready suits, and related support to over $1 billion through
fiscal year (FY) 2025, when the first two flight-ready spacesuits will be available based on current xEVA
schedules.12

<blink>

Hard to find numbers on Apollo era suit dev costs. I found some pages claiming that suit dev was $22M from the 70s (maybe the current suits?). That's $154M in 2021 dollars.

A billion for suit dev seems... excessive.

Recent RFP for commercial suits:

https://sam.gov/opp/1ddea0dd9b564a6d9e2c33b7058dac3e/view

 

And Elon chimes in:

 

 

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One of the stated concerns in the OIG report is that the suits might sit at Gateway for years between uses, unlike ISS suits which are under constant maintenance.

The simple solution to that is, "Don't leave them at Gateway."

The trouble of course is that mass margins to cislunar are so very, very tight. SLS Block 1 just barely throws Orion to TLI (in fact SLS Block 1 can't actually throw Orion to TLI, Orion needs to use the SM for the final burn). Every gram matters.

Dragon XL can bring them up, obviously, but then they are stuck at Gateway. Since they are ridiculously expensive (and mission critical), they have to be perfect. The enemy of good is perfect as my father in law always says.

Nothing from other proposed landers comes back to Earth, and Orion might not have the room cause it is tiny.

Bring suits back in LSS, refurb them and send them back with each crew.

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41 minutes ago, cubinator said:

I would like to see a compression based space suit instead of a suit filled with air. I think that would offer the comfort and mobility needed to spend long days working outdoors on the Moon and Mars.

Latex.

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  • 2 weeks later...
11 minutes ago, kerbiloid said:

It has become a good worldwide tradition, to celebrate achievements in advance.

And when the celebration has been already celebrated, why keep the headache with the achievement? It won't add much to the good mood anyway.

Beats not saying it out loud, trying anyway, then saying "we were never trying for that in the first place, we did this other thing!" when it fails.

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