NASA's Artemis Program Updates and Discussion Thread 5

[deadman1204]

There's no such thing as AII or AIII.
Please use the correct terminology.
The standards on NSF are higher than on Redit and other such platforms that accept nearly anything as appropriate.
NSF does not.

Its pretty clear to all what that abbreviation means. No need to grammar nazi over it

[Coastal Ron]

There's no such thing as AII or AIII.
Please use the correct terminology.
The standards on NSF are higher than on Redit and other such platforms that accept nearly anything as appropriate.
NSF does not.

Its pretty clear to all what that abbreviation means. No need to grammar nazi over it

NSF has an audience of people reading forums sometimes very frequently, but sometimes very infrequently.

If you are having a mini conversation with someone over a short period of time, then removing a name and substituting the first letter of that name maybe won't lose the context for the people having the conversation, but if someone who hasn't visited the forum recently tries to come up to speed with what is going on, they are not going to know what that first letter means.

I know about the Artemis program, but I've been on travel for a while and hadn't checked into this forum, and I certainly wouldn't know - for certain - what "AII" or "AIII" would be.

If you want to have a private conversation in DM's, then use whatever acronyms you want. But if you want to talk publicly to a wide audience, then you need to ensure that whatever terms you use will be understood by everyone.

My $0.02

[deadman1204]

There's no such thing as AII or AIII.
Please use the correct terminology.
The standards on NSF are higher than on Redit and other such platforms that accept nearly anything as appropriate.
NSF does not.

Its pretty clear to all what that abbreviation means. No need to grammar nazi over it

NSF has an audience of people reading forums sometimes very frequently, but sometimes very infrequently.

If you are having a mini conversation with someone over a short period of time, then removing a name and substituting the first letter of that name maybe won't lose the context for the people having the conversation, but if someone who hasn't visited the forum recently tries to come up to speed with what is going on, they are not going to know what that first letter means.

I know about the Artemis program, but I've been on travel for a while and hadn't checked into this forum, and I certainly wouldn't know - for certain - what "AII" or "AIII" would be.

If you want to have a private conversation in DM's, then use whatever acronyms you want. But if you want to talk publicly to a wide audience, then you need to ensure that whatever terms you use will be understood by everyone.

My $0.02

Wow get over yourself. This is a public message board, not official government documentation. Its crap like this that has driven most of the old guard away. Well that and attacking anyone who doesn't properly worship the correct billionaire...

This is a place for discussion. criticizing people for not using official government acronyms because of "posterity and precedent" is just needless pearl clutching and concern trolling.

[zubenelgenubi]

Moderator:
It's good form to use full names, or at least full acronyms, in discussions.  Ad hoc abbreviations often decrease comprehension, not increase it.

Are we really in such a hurry that we can't type out Artemis? 😫

Wow get over yourself.

Yes, please do. 🙏

Carry on.

[woods170]

Also, I realized that the EFT-1 boilerplate could only be 4.6m wide, because that's as wide as the D-IVH's static envelope would allow.  The live CM has a 5.0m heat shield.

You are mistaken multiple times.

First: EFT-1 did NOT fly a boilerplate capsule. It had the full pressure vessel, the full set of RCS and flight computers, the full set primary TPS, back-shell TPS and operational parachutes. What was mostly lacking was ECLSS and crew systems and the live service module.

Second: EFT-1 was a live CM, featuring the full 5.0 meter diameter. You have to remember that EFT-1 did not fly inside the Delta IV H fairing. Instead, the set up was nearly identical to what was flown on Artemis 1: Orion stage adapter connected the Delta IV H DCSS to the a boilerplate Service Module, which carried a full 5.0 m diameter CMA and full 5.0 m Command Module, topped off by a a full-size LAS (albeit with an inert abort motor).

I stand doubly corrected.

So, given that:

1) Why did they change the heat shield design between EFT-1 and Arty-1?

If you're too lazy to even read the stuff provided to you via the links in my previous post, then I can't help you.

Having said that,
Go to the second link in my previous post: its a PDF on NTRS and it spells out the lessons learned from EFT-1, including WHY they moved from a monolithic Avcoat heat shield to one constructed from Avcoat blocks.
Note: Artemis missions 1 and 2 were originally called Exploration Mission 1 (EM-1) and Exploration Mission 2 (EM-2).

Hope this helps and I really hope you do your own research first next time.

[Paul451]

There's no such thing as AII or AIII.
Please use the correct terminology.

Its pretty clear to all what that abbreviation means.

NSF has an audience of people reading forums sometimes very frequently, but sometimes very infrequently.
I know about the Artemis program, but I've been on travel for a while and hadn't checked into this forum, and I certainly wouldn't know - for certain - what "AII" or "AIII" would be.

It's standard even in professional literature and most publication style-guides that you only need to include the full expansion of an abbreviation at the first use. My post included a quote at the very top of the post that had the full name for both flights, in a thread with the program name in the title. No-one was confused.

I accept the umpire's decision, of course, but I'd prefer if people like CLongton and Deadman would dial down the instant escalation to insults and bitchiness over something so trivial.

[JohnFornaro]

But yes, I think it's clear that the problems at NASA go much deeper than any firing any senior managers or terminating a particular vehicle can address. It's fundamental to the organization in more profound ways.

I have a grand total of 12 sources all over NASA ... [who have] told me stuff that confirms my bolding above. The rot that is destroying NASA from the inside out, has penetrated all major aspects of NASA ... But if nothing is done to radically and permanently cut away the rot, it will eventually affect everyone working there. At that point NASA becomes a total loss. And that's happening faster than most people (including some NASA employees) can imagine.

Elon's example when he purchased Twitter comes to mind as a conceptual approach to solving this problem.

Part of the characterization of the "Rot" you mention is exemplified in the "AII and AIII" sidetrack above, where progress in the discussion comes to a complete halt because of an unwillingness of the participants to acknowledge understanding unless specific words are used, along with an unwillingness to acknowledge an error, no matter how trivial, and an unwillingness to offer/accept mildly expressed correction.

We have met the enemy and he is us, to coin a phrase.

[deadman1204]

Moderator:
It's good form to use full names, or at least full acronyms, in discussions.  Ad hoc abbreviations often decrease comprehension, not increase it.

Are we really in such a hurry that we can't type out Artemis? 😫

Wow get over yourself.

Yes, please do. 🙏

Carry on.

[DanClemmensen]

If I remember correctly, SpaceX modified the original pica formulation and renamed it PicaX to make Dragon's heatshield capable of EDL at lunar and interplanetary return velocity. It was in 2016 that SpaceX announced the Red Dragon program for a Mars Sample Return mission. PicaX was developed to support that. Anyone else remember this? If so, I think this would be a good time to test that for real.

Are you proposing that NASA should test a PicaX heat shield on Orion, or that SpaceX should test a Dragon on a high-velocity return mission?

If Orion, what does the test mission look like? Uncrewed Artemis I re-run?

If Dragon, how would this fit into Artemis?

[clongton]

If I remember correctly, SpaceX modified the original pica formulation and renamed it PicaX to make Dragon's heatshield capable of EDL at lunar and interplanetary return velocity. It was in 2016 that SpaceX announced the Red Dragon program for a Mars Sample Return mission. PicaX was developed to support that. Anyone else remember this? If so, I think this would be a good time to test that for real.

Are you proposing that NASA should test a PicaX heat shield on Orion, or that SpaceX should test a Dragon on a high-velocity return mission?

If Orion, what does the test mission look like? Uncrewed Artemis I re-run?

If Dragon, how would this fit into Artemis?

For Dragon, not Orion. And it would be less than optimal to try to fit anything into Artemis. It would take forever. SpaceX should fly a heatshield demo on its own dime.

[clongton]

I accept the umpire's decision, of course, but I'd prefer if people like CLongton and Deadman would dial down the instant escalation to insults and bitchiness over something so trivial.

1. There is nothing escalating, bitchy nor insulting in my brief statement - nor was any insult or derogatory attitude implied.
It was a simple statement of fact and a request to comply with standards; professionally and briefly stated. Nothing more.

2. It's not trivial. Using unknown abbreviations that need to be subjectively interpreted takes away from what could otherwise be a professional exchange of thoughts and ideas and could result in an erroneous interpretation. Proper use of correct terminology eliminates this possibility.

Please don't be so quick to assume motive to another person's words.
If it's important to you to know why then just ask.

[DanClemmensen]

If I remember correctly, SpaceX modified the original pica formulation and renamed it PicaX to make Dragon's heatshield capable of EDL at lunar and interplanetary return velocity. It was in 2016 that SpaceX announced the Red Dragon program for a Mars Sample Return mission. PicaX was developed to support that. Anyone else remember this? If so, I think this would be a good time to test that for real.

Are you proposing that NASA should test a PicaX heat shield on Orion, or that SpaceX should test a Dragon on a high-velocity return mission?

If Orion, what does the test mission look like? Uncrewed Artemis I re-run?

If Dragon, how would this fit into Artemis?

For Dragon, not Orion. And it would be less than optimal to try to fit anything into Artemis. It would take forever. SpaceX should fly a heatshield demo on its own dime.

Why would SpaceX do that? Where would it fit into SpaceX' plans? As far as I can tell SpaceX wants to use Starship for any BLEO missions, and Starship it supposed to use a refractory reusable TPS, not an ablative TPS. Perhaps you are thinking of some replacement for SLS/Orion that includes a Dragon returning from cislunar space?

(Separately, according to Wikipedia Dragon now uses a newer version called PICA-3 instead of the earlier PICA-X, but I have zero insight into the details).

[clongton]

If I remember correctly, SpaceX modified the original pica formulation and renamed it PicaX to make Dragon's heatshield capable of EDL at lunar and interplanetary return velocity. It was in 2016 that SpaceX announced the Red Dragon program for a Mars Sample Return mission. PicaX was developed to support that. Anyone else remember this? If so, I think this would be a good time to test that for real.

Are you proposing that NASA should test a PicaX heat shield on Orion, or that SpaceX should test a Dragon on a high-velocity return mission?

If Orion, what does the test mission look like? Uncrewed Artemis I re-run?

If Dragon, how would this fit into Artemis?

For Dragon, not Orion. And it would be less than optimal to try to fit anything into Artemis. It would take forever. SpaceX should fly a heatshield demo on its own dime.

Why would SpaceX do that? Where would it fit into SpaceX' plans? As far as I can tell SpaceX wants to use Starship for any BLEO missions, and Starship it supposed to use a refractory reusable TPS, not an ablative TPS. Perhaps you are thinking of some replacement for SLS/Orion that includes a Dragon returning from cislunar space?

(Separately, according to Wikipedia Dragon now uses a newer version called PICA-3 instead of the earlier PICA-X, but I have zero insight into the details).

Actually I think that Dragon is a potential replacement for Orion.

Usable Internal Volume
Orion usable space: 316 cubic feet (8.95 cubic meters).
Dragon usable space: 328 cubic feet (9.30 cubic meters), 12 cubic feet more than Orion.

Life Support
In terms of life support capability, the Dragon spacecraft is capable of sustaining crew for up to 7 days by itself, while Orion (without the service module) only up to 1 day.
Orion's service module (which Dragon does not have) carries the majority of the consumables, extending the capsule's life support from 1 day to 21 days. While Dragon does not have a service module, it does have an empty trunk, which could could relatively easily be converted to a service module to supply the consumables. That would extend Dragon's capability to at least equal Orion's, if not exceed Orion's capability.

Propulsion
Orion's propulsion (like Apollo) is provided by propellant and engine in the service module. It has no other independent propulsion capability.
Dragon's propulsion is provided by Super Dracos mounted within the spacecraft itself, providing the spacecraft with limited independent propulsion. But propellant and Super Dracos could also be included in a Trunk that has been modified to function as a Service Module, to provide the TLI, LOI and TEI burns.

Reentry
PICA-3 can withstand temperatures in excess of 2,400°C (4,350°F). This high thermal tolerance makes it effective for spacecraft re-entering Earth’s atmosphere at very high velocities. This material was specifically developed for high-speed re-entries, like the now cancelled Red Dragon program making a direct reentry from Mars, and its properties are designed to handle the intense heat generated by returning from deep space. PICA-3 is a newer material than Avcoat and has been used in high-speed re-entry missions, such as NASA's Stardust mission, which returned at one of the highest re-entry speeds ever recorded (12.9 kilometers per second (28,900 miles per hour), far exceeding the reentry speed and thermal environment of a lunar return. A spacecraft with a PICA-3 heat shield would definitely be capable of surviving Earth re-entry from a lunar trajectory. The material's high thermal tolerance and efficient ablation properties, make it well-suited for the purpose of high-speed re-entries from lunar orbit. Of course, we would need an actual demonstration of the spacecraft's heatshield's ability to successfully tolerate EDL from a lunar TEI trajectory. This is the missing capability that spawned this discussion.

Conclusion
So yes, I am contemplating using Dragon instead of Orion. The major difference is that SpaceX would need to create a variant of the trunk that functions as a service module. As for the spacecraft, it is already fine. Very little modification would be needed to the capsule, which by itself has 7x the life support of Orion. The only large scale modification needed would be to modify the empty trunk to create a service module to supply additional consumables and propulsion.

I do note in passing that all the potential space stations undergoing design or under actual development picture Dragon, Dreamchaser, Starliner or Orion as the transportation link. Starship is not included in the mix.

Note that all of this is just a thought exercise. Whether or not this would interest SpaceX is another matter.

[DanClemmensen]

Why would SpaceX do that? Where would it fit into SpaceX' plans? As far as I can tell SpaceX wants to use Starship for any BLEO missions, and Starship it supposed to use a refractory reusable TPS, not an ablative TPS. Perhaps you are thinking of some replacement for SLS/Orion that includes a Dragon returning from cislunar space?

Actually I think that Dragon is a potential replacement for Orion.
Orion usable space: 316 cubic feet (8.95 cubic meters).
Dragon usable space: 328 cubic feet (9.30 cubic meters), 12 cubic feet more than Orion.

Thanks for the clarification. Basically, you think it is easier to replace Orion than it is to fix its heat shield. That sounds right to me. My concern is that the approach you outlined will require a fair amount of new development, which may take as much or more time as fixing Orion's heat shield, so we are adding years to the Artemis III schedule. You did not mention which LV would be used: do you have a recommendation?

I still prefer changing the mission architecture entirely that eliminates SLS and Orion. Use Dragon for Earth-LEO and LEO-Earth, use (refuelled) Starship for LEO-NRHO-LEO, and use Starship HLS for NHRO-Moonsurface-NRHO. This does not require any new hardware design beyond what is already needed for Artemis III, because the transit Starship can be a separate instance of Starship HLS.

[clongton]

Actually I think that Dragon is a potential replacement for Orion.
Orion usable space: 316 cubic feet (8.95 cubic meters).
Dragon usable space: 328 cubic feet (9.30 cubic meters), 12 cubic feet more than Orion.

Thanks for the clarification. Basically, you think it is easier to replace Orion than it is to fix its heat shield. That sounds right to me. My concern is that the approach you outlined will require a fair amount of new development, which may take as much or more time as fixing Orion's heat shield, so we are adding years to the Artemis III schedule. You did not mention which LV would be used: do you have a recommendation?

For the time being, Falcon-9.

I still prefer changing the mission architecture entirely that eliminates SLS and Orion.

Agreed.

Use Dragon for Earth-LEO and LEO-Earth, use (refueled) Starship for LEO-NRHO-LEO, and use Starship HLS for NHRO-Moon surface-NRHO. This does not require any new hardware design beyond what is already needed for Artemis III, because the transit Starship can be a separate instance of Starship HLS.

Change the architecture. Get rid of SLS and Orion. Move Gateway to Lunar orbit. Send Dragon directly to lunar orbit to dock with Gateway where HLS is docked. Crew transfers to HLS at Gateway Station for the mission. When completed, return to Gateway Station, crew transfers to Dragon and comes directly home. Everything else stays the same. Fixing Orion just makes the same awful excuse for a program possibly work. Cargo Starships on a one-way trip can be sent as needed with massive amounts of surface supply and equipment. Switching to Dragon changes the focus of Artemis from giving SLS something to do (launch Orion) to an actual lunar exploration program. As surface capabilities develop and evolve, so can the scope of the program. This approach gives Artemis a chance to become an actual lunar exploration and exploitation program, something it will never be in its current iteration.

[darkenfast]

Clongton, I used to think that using Dragon to replace Orion was a non-starter. Then SpaceX got a contract to build a new version of their vehicle to de-orbit the ISS, and it includes an extended trunk with tanks and thrusters and a Dragon (of some sorts), on top. Since they will have that, and they will presumably have a modification to the access arm (this Dragon will be higher up), I think the possibility of a replacement for Orion has become more realistic, and part of it has been paid for.

The key is: how long it will take for NASA to decide that astronauts can fly on Starship.

[dglow]

I accept the umpire's decision, of course, but I'd prefer if people like CLongton and Deadman would dial down the instant escalation to insults and bitchiness over something so trivial.

1. There is nothing escalating, bitchy nor insulting in my brief statement - nor was any insult or derogatory attitude implied.
It was a simple statement of fact and a request to comply with standards; professionally and briefly stated. Nothing more.

2. It's not trivial. Using unknown abbreviations that need to be subjectively interpreted takes away from what could otherwise be a professional exchange of thoughts and ideas and could result in an erroneous interpretation. Proper use of correct terminology eliminates this possibility.

All well and good, but understand this runs against the natural tendency of language: Brevity Law.

And @Paul451 explicitly advocated for the use of abbreviations only after they have been introduced through the fully-expanded term – a practice journals and professional publications adhere to.

[clongton]

And @Paul451 explicitly advocated for the use of abbreviations only after they have been introduced through the fully-expanded term – a practice journals and professional publications adhere to.

A practice that all professionals adhere to when writing.
The Brevity law is specifically cautioned against in college English.

[clongton]

The key is: how long it will take for NASA to decide that astronauts can fly on Starship.

Private crew will fly on Starship long before NASA will put its astronauts onboard. For example, Jared Isaacman has stated that his team intends to crew at least one Starship mission. SpaceX is quietly building up its own astronaut corps. Two (2) of the crew on the last Polaris Dawn mission were SpaceX astronauts. NASA has become so risk averse and is so deeply cemented into the military industrial complex that it, unbelievably, runs the risk of eventually becoming irrelevant with regard to human spaceflight. SpaceX is not trying to outshine NASA, but is simply not waiting for it.

[DanClemmensen]

The key is: how long it will take for NASA to decide that astronauts can fly on Starship.

Private crew will fly on Starship long before NASA will put its astronauts onboard. For example, Jared Isaacman has stated that his team intends to crew at least one Starship mission. SpaceX is quietly building up its own astronaut corps. Two (2) of the crew on the last Polaris Dawn mission were SpaceX astronauts. NASA has become so risk averse and is so deeply cemented into the military industrial complex that it, unbelievably, runs the risk of eventually becoming irrelevant with regard to human spaceflight. SpaceX is not trying to outshine NASA, but is simply not waiting for it.

Minor clarification: NASA intends to put crew on Starship HLS during Artemis III. We are discussing crewed Earth launch and Earth landing, not Starship in general. I expect to see a Starship CLD served by Crew Dragon before I see a crewed EDL Starship.

NASA risk: Elon has stated many times that SpaceX intends to fly "hundreds" of uncrewed EDL missions before flying a crewed EDL mission. IMO this would make the first crewed EDL Starship mission a whole lot less risky than the first crewed Orion mission. "Hundreds" probably implies Starlink missions.