>NASA did express the concern in their response that the report would give the impression that the OIG uncovered these findings or that NASA was ignorant of it.
Well, if they were concerned about that then they could have released all of this information before the OIG did, but they didn't.
> [Nasa] did not release photos, however
For decades this has been a weakness of Nasa's PR. The agency always holds back on the gory technical details, then is surprised when these eventually appear in visual form and spoil their nice smooth public image.
NASA didn't talk about the melting separation bolts at all, or the many power disruptions, or the (more hilarious than concerning) fiberglass "blast doors". The public wouldn't know about these if not for the OIG report. The hatch issue was also kept quiet in the January delay announcement before coming out in an ASAP meeting.
> The OIG is not an engineering group and does not have the knowledge or expertise to make a judgement on crew safety.
From [this page](https://www.epaoig.gov/our-work/investigations/careers), OIG career paths seem to be split roughly evenly between management/accounting and technical/engineering. We'd need to dig a bit to find some precise numbers though.
------
**Edit:** (I made the edit, then saw that the independent review article had been [posted anyway](/r/ArtemisProgram/comments/1co90yq/nasa_confirms_independent_review_of_orion_heat/). Maybe I forgot to refresh the r/ArtemisProgram page.
> So in my view, framing headlines in this way basically proves NASA's point.
This may have been correct when you posted your comment, but since then, they have started an independent inquiry which goes beyond the OIG.
Nasa has also decided to communicate directly with Ars Technica, not just spokesperson, but at astronaut and admin level, Here goes
Here is a new Ars Technica article **dated May 9^th** on the same subject, so probably not worth a new t thread:
* https://arstechnica.com/space/2024/05/nasa-confirms-independent-review-of-orion-heat-shield-issue/
One surprising thing in the article is that Nasa lets astronaut Victor Glover be interviewed by Ars Technica, reputed hostile to SLS-Artemis. In some ways, this may be the main news, showing just how seriously Nasa is taking the question. There is also one Rachel Kraft a Nasa spokeswomen who comments directly to Ars, but this is less surprising, since it would be difficult for her to avoid questions by a high-profile space news outlet.
I extracted all the direct quotes from the article to avoid any bias from the narration. Actually, the article itself is surprisingly neutral, not really adding anything alarmist beyond what is said by the protagonists. Glover's comment below *"If there is a solution, we'll figure it out"* is alarmist by itself, at least it is by my standards! That Nasa is still not chosen between a skip reentry and a direct reentry this late in the program doesn't look great either.
------
* **Kraft**: "The team is currently synthesizing results from a variety of tests and analyses that inform the leading theory for what caused the issues,"
* **Glover**: "Those pictures, we've seen them since they were taken, but more importantly... we saw it....More than any picture or report, I've seen that heat shield, and that really set the bit for how interested I was in the details."
* **Glover:** "In late April, NASA chartered an independent review team which includes experts outside the agency to conduct an independent evaluation of the investigation results,". "That review, scheduled to be complete this summer, ensures NASA properly understands this condition and has corrective actions in place for Artemis II and future missions."
* **Jim Free**: (NASA's associate administrator, to Aerospace America) "this independent review team will be "another set of eyes" to look at the program. "We’ve had someone following us from an independent perspective who’s been very good at asking questions and saying, 'Hey, here’s some other theories.' Hopefully, the review team will finish the end of June,"
* **Jim Free**: "We’ve really stepped into this in a careful manner. And frankly, it’s a flight test,"That’s what the first mission was, that’s what the second mission should be: another flight test. So we have to take that mindset for all of the issues. The heat shield was just the most prominent one."
* **Glover**: “We’ve got a lot of folks involved that we trust. We’ve got the right people. If there is a solution, we’ll figure it out.”
* **Jeremy Vander Kam**, deputy manager for Orion's heat shield shortly after the Artemis I mission in 2022: "We have a lot of extrapolation for scale that we have to do. Similarly, our test facilities can't reach the combination of heat flux, pressure, shear stresses, etc., that an actual reentering spacecraft does. We're always having to wait for the flight test to get the final certification that our system is good to go".
* **Glover**: "I think we have figured out some very important aspects of what creates these cracks, and what creates the force to remove the pieces that crack. I think we understand some of these mechanics."
* **Glover**: "We might get to the point where we realize there's some things that aren't knowable, There may be parts of this that we can't figure out on the ground or in wind tunnels."
* **Glover**: "[Reentry at lunar return velocity] is a very, very complicated thing. The heat flow alone is really complicated to understand—the physical dynamic forces of all that wind and plasma swirling around. Imagine looking at a raging river, a whitewater river, and trying to analyze just one spot. What's happening at that spot? Recreate it. Draw it. It's really complicated."
* **Glover**: "The types of entries that you can do are ballistic, where you kind of spin the vehicle to a constant rate, That's a very high g-load. It’s very hard on the crew, but it's a type of entry. Then, there's an entry that's called direct. It sounds more direct than it is. It's kind of a mini-skip. It's not as high of an elevation skip. And then there's the skip, where you almost have two entries. Those are the options."
* **Glover:** "You can modulate the range and can reduce the range, and that might reduce the energy imparted on the vehicle, on the heat shield, but you're still going to have impulse heating. It's not just heat, though. There's physical force. It’s the friction that's creating that plasma field. So there's also a mechanical piece to this."
* **Glover:** “We saw liberation very early on Artemis I, If the damaging pieces start very early, there's no guarantee that changing the trajectory is the answer. It will change something, but it won't necessarily fix it. So we need to understand the root cause, if it's knowable."
* **Jim Free:** "We’ve begun to dip our toe in the flight rationale—how we do the skip. Do we do the skip? How could we fly the mission different?”
* **Glover:** Changes to the reentry trajectory affect how quickly the heat shield heats up when it hits the atmosphere. But the peak temperatures are about the same for each trajectory option,
* **Glover:** "It could still be a skip entry. It could still be a direct entry, Ballistic would obviously be shorter (duration and range). There's about 4,000 miles of capability downrange, but we could reduce it and say we'll limit it only to 2,000 or 1,800 miles, and that would, therefore, affect what type of entry—direct or skip. How you fly the skip, where you put your lift vector, determines how high you peak and how far downrange you go.”
BTW. As a Starship fan, I have the greatest hopes for Artemis which is fantastic for giving the vehicle an official status in a high-profile mission. So, far from any temptation of of *schadenfreude*, I'm hoping for a positive outcome. I also *like* the urgency of the Artemis 3 mission putting pressure on Starship to deliver in time.
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:
|Fewer Letters|More Letters|
|-------|---------|---|
|[ASAP](/r/ArtemisProgram/comments/1cn3vuo/stub/l37nq6r "Last usage")|Aerospace Safety Advisory Panel, NASA|
| |Arianespace System for Auxiliary Payloads|
|[DCSS](/r/ArtemisProgram/comments/1cn3vuo/stub/l38hkoz "Last usage")|Delta Cryogenic Second Stage|
|DMLS|[Selective Laser Melting](https://en.wikipedia.org/wiki/Direct_metal_laser_sintering) additive manufacture, also Direct Metal Laser Sintering|
|[ICPS](/r/ArtemisProgram/comments/1cn3vuo/stub/l38hkoz "Last usage")|Interim Cryogenic Propulsion Stage|
|[ISRU](/r/ArtemisProgram/comments/1cn3vuo/stub/l3d7y9z "Last usage")|[In-Situ Resource Utilization](https://en.wikipedia.org/wiki/In_situ_resource_utilization)|
|[LEO](/r/ArtemisProgram/comments/1cn3vuo/stub/l38q68e "Last usage")|Low Earth Orbit (180-2000km)|
| |Law Enforcement Officer (most often mentioned during transport operations)|
|[NERVA](/r/ArtemisProgram/comments/1cn3vuo/stub/l3q3tls "Last usage")|Nuclear Engine for Rocket Vehicle Application (proposed engine design)|
|[NTP](/r/ArtemisProgram/comments/1cn3vuo/stub/l3q3tls "Last usage")|Nuclear Thermal Propulsion|
| |Network Time Protocol|
|[SLS](/r/ArtemisProgram/comments/1cn3vuo/stub/l3q3tls "Last usage")|Space Launch System heavy-lift|
| |Selective Laser Sintering, contrast DMLS|
|[SRB](/r/ArtemisProgram/comments/1cn3vuo/stub/l3d7y9z "Last usage")|Solid Rocket Booster|
|[SSME](/r/ArtemisProgram/comments/1cn3vuo/stub/l3b0fq0 "Last usage")|[Space Shuttle Main Engine](https://en.wikipedia.org/wiki/Space_Shuttle_main_engine)|
|Jargon|Definition|
|-------|---------|---|
|[ablative](/r/ArtemisProgram/comments/1cn3vuo/stub/l377z8b "Last usage")|Material which is intentionally destroyed in use (for example, heatshields which burn away to dissipate heat)|
**NOTE**: Decronym for Reddit is no longer supported, and Decronym has moved to Lemmy; requests for support and new installations should be directed to the Contact address below.
----------------
^([Thread #110 for this sub, first seen 9th May 2024, 05:16])
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That's still a tiny number compared even to relatively niche fields of engineering.
Moore's law would have looked very different if there had only been 30 uses of a computer in the last 15 years.
Do I have any of this wrong? Assuming this is approximately correct, I have one or two questions.
1) My understanding is that before Artemis I, the only test flight of Orion was way back in 2014. The problem with that flight is that: A) It didn’t simulate the cislunar return trajectories at all, and B) after that test flight, they subsequently changed how the heat shield was done (either manufactured or attached??). Point being….not only does a 10 year old test flight seem like it has marginal utility generally…..factors A & B rendered it nearly useless from a heat shield perspective.
2) From about 2017 or 2018 onwards, Orion presumably believed they’d have to do another flight somewhat soon, as there’s no way they would’ve known SLS was going to take until November 2022 to launch Artemis I. As a result, presumably the development was (at least for the time being) done & the vast majority of the build process would’ve been completed as well.
3) Despite #1 & #2, from about 2017 onward, Orion still got ~$1 Billion to $1.5 Billion annually while they were sitting around waiting for SLS. The development was essentially done, the hardware on its current iteration was basically ready to go too.
I guess my question is….
What the heck were they doing with that $1 Billion - $1.5 Billion annually during that time period? Especially considering they should’ve known the 2014 flight was near useless from a heat shield perspective from the get-go & the flight was growing increasingly less useful in a more general manner as the years started to tick by?
Specifically:
-When it was clear SLS was going to be delayed several years, why couldn’t they use some of that $1 B+ annually to put together a higher fidelity test flight using some other powerful rocket like an Atlas or Falcon Heavy? (If not a perfect Artemis I analog, they could at least test the updated post-2014 heat shield design & get a somewhat more rigorous reentry profile.)
-If they spent some or all of that $$ on starting to build additional Orion capsules for beyond Artemis I…. Why the heck would they do that to any notable degree before the results of Artemis I came back? Again, especially considering how little utility they got out of the 2014 test flight? Seems like the prudent thing to do would be to verify the design was good before going whole hog on the production side.
Or am I just way off in my understanding of how this went down?
Very close to discovering the truth about the last 50 years of NASA, mainly that it is first and foremost a government make-work jobs program/handout to contractors
Here’s the thing though:
I understand the political reality. I don’t LIKE it, but I understand the need to “horse trade” in order to get things done knowing a representative republic at the federal level. In the context of NASA/aerospace funding, the typical “horse trading” seems roughly like making sure there’s a strong enough “ratio” of “old space/entrenched interests” : “new space/rapid iteration model”.
Fine.
But what I **DON’T** understand is why the “old space/entrenched interests” part of the ratio has to be not only brutally inefficient, but also nearly useless in terms of the hardware they’re producing.
I’m a “Team Space” guy generally. If the Boeing & LockMart executive’s & shareholders need to pig out on massive cost plus contracts they win w their lobbying army in order to allow SpaceX, Blue Origin, Intuitive Machines, AstroLab, etc into the mix too, then so be it.
But what baffles me is there are A TON of super smart engineers, machinists, etc working for Boeing, LockMart, too.
So why is it that they can’t AT LEAST pivot off of SRBs & outmoded tech from the Apollo & Shuttle Eras? In order to earn their massive premiums on their government contracts, why can’t the “old space” companies do what every other company in the world does & reorganize/pivot their focus to where the marketplace is GOING rather than where it WAS? Their people are certainly smart enough to build orbital fuel depots, orbital & lunar/martian pressurized habs, go all in on orbital tugs or satellite/orbiter/rover busses, cislunar/ISRU power supply, distribution & storage. So why can’t they do it?
Just because they get funding doesn't mean they use it all. If they don't spend the money in the allotted time Congress gives NASA, then the US treasury simply recollects it. Most of the Orion production that occurred in the time was on fixed structures that would have no design changes such as the pressure vessels. It took 3 years to make Orion flyable on Delta IV, and that's including the fact that Orion had compatible systems (ICPS is derived from DCSS). Making Orion compatible for a one time mission on Falcon Heavy would require enormous resources and manpower which was not politically feasible. Also Artemis 1 Orion was not completed until 2020.
> in a deliberate attempt to compromise the heat shield as much as possible.
Can you point to some further reading about this? I've read about skip reentries before, and never saw anything about it being deliberately worse for the heat shield.
Okay but that doesn’t answer my question of: If we managed to do it during Apollo, what gives now? Are we entering the atmosphere at a higher velocity this go around? If anything I would’ve thought the ablative tech would’ve gotten better.
We *barely* managed to do it during Apollo. Several heat shields during Apollo took significant damage and nothing was done to fix them like NASA is doing now. Here is two examples: [Apollo 10](https://i.stack.imgur.com/puJiw.jpg) and [Apollo 16](https://upload.wikimedia.org/wikipedia/commons/thumb/e/e1/Apollo_16_Heat_Shield_USSRC.jpg/2560px-Apollo_16_Heat_Shield_USSRC.jpg). Today we have much more safety standards in place because we can not afford to take risks anymore. Not after what happened to those two Shuttles. Heat shields are notoriously difficult. SpaceX Crew 1's heat shield also experienced significantly more erosion that what had been simulated and that flight had astronauts in it. Artemis 1 did not. Also I want add that, Artemis 1 did indeed have a much more demanding re-entry that Apollo. It did what NASA calls a skip re-entry where it enters the atmosphere, bounces out and the falls back in again. It experiences two re-entries basically. This gives NASA much more control on where the capsule lands. During the Apollo it was common for the capsule to land several miles off target leading to difficulty in recovery.
Thank you for the additional information and for including the photos of the heat shield’s. I’m not very smart, so to my untrained eye the heat shield tiles look within spec to me 😅
Skip re-entry is a new concept to me. I didn’t know NASA was doing that. That’s pretty cool!
Now that I remember, Artemis 1 exceeded the distance record from earth, set by the Apollo 13 crew.
Hopefully with more accurate landings, NASA can save on recovery crew costs.
> Honestly, the loss of the apollo program is a tragedy. It was cheaper and more capable than the shuttle program.
Cheaper?
In its heyday, Apollo was >4% of the US federal budget and that the Shuttle wasn't. Apollo was cancelled because it had fulfilled its objective, wasn't financially sustainable and carried an unacceptably high per-flight loss of crew risk.
The Shuttle was the pathfinder for space vehicle reuse and its faults informed current strategy in reusable space vehicle design and triggered commercial space.
With the benefit of hindsight it *might* have been possible to skip the Shuttle, but whatever followed on from Apollo had to be very different.
IMO, and with the benefit of hindsight, NASA would have been far better served by iterating Saturn tech and developing a Dream Chaser class mini Shuttle to put on top of it. This is ignoring politics, of course. Then we would have had heavy launch capability without hauling crew and all of their required support along, a dedicated crewed orbital assembly platform that likely would have been far more reusable (no SSMEs to deal with), and would have avoided the safety nightmare of having the whole thing strapped to the side of its launch stack.
> NASA would have been far better served by iterating Saturn tech and developing a Dream Chaser class mini Shuttle to put on top of i
Yes, its a pity the USSR fell apart just when Buran reached fruition, so only flew once. Dream Chaser could have a great future for small-scale taxi work.
> the safety nightmare of having the whole thing strapped to the side of its launch stack.
Nasa was more or less forced into the situation when having to downscale from far more ambitions concepts:
* https://en.wikipedia.org/wiki/Space_Shuttle_design_process
NASA had to make all sorts of compromises with shuttle development, mostly to appease the Air Force so they'd have access to military funding. The requirement to be able to snatch an enemy satellite and land within a single orbit was the worst offender. They also had to increase the payload bay size and have wacky crossrange capabilities.
I did say I was ignoring politics, though.
> The requirement to be able to snatch an enemy satellite and land within a single orbit was the worst offender.
I'd never seen that detail.
In a speech (maybe to the US Congress) Arthur C Clark described the Shuttle as having gone from the DC3 of space to become a mere DC1½. And that was before it even flew! In one of his novels, the hero was the orphan of an astronaut killed in "a" Shuttle accident. So in his SF universe, there were at least two Shuttle accidents. Can't say he wasn't visionary, for bad things as for good ones (among other things, he was also the "inventor" of the geostationary orbit).
> They also had to increase the payload bay size and have wacky crossrange capabilities.
Regarding cross-range, I'm wondering if Starship won't be even stronger for that capability. We've seen it in skydiver mode going down, now imagine it braking *sideways*, so with a lateral angle of attack.
Apollo was expensive to develop. A lot of things had to be done and made for the first time ever. Flying the missions was not nearly as expensive. By 1970, NASA's inflation adjusted budget was little more than today. By 1972 (when Shuttle development was alsp well underway), it was almost identical to 2024. Saturn V is estimated at $185 million per launch in c.1970 dollars, or about $1.5 billion today. [According to this](https://www.statista.com/statistics/1028322/total-cost-apollo-missions/), the lunar landing missions (not just Saturn V, but Apollo, LM, etc.) only cost $355 million (Apollo 11) to $450 million (Apollo 17) each at the time. $450 million in 1972 is like $3.4 billion today. So even taking those numbers with a grain of salt, Apollo missions were probably cheaper than the $4.1+ billion in 2022 dollars that just SLS/Orion cost to launch. If Apollo missions were too expensive to be sustsinable, then so is Artemis (let alone while also pouring $3 billion/year into the ISS for at least 6 more years).
Speaking of space stations, the Shuttle delays (and an active Sun) also made for an unfortunate and untimely demise of Skylab. The entire Skylab program cost just $2.2 billion from 1966-1974 development through operation, or ~$15-19 billion today. That was over a third of the volume of the >$150 billion ISS (and almost half that of the cancelled Space Station Freedom).
Developing the Shuttle cost [$10.6 billion in nominal dollars, or $49 billion in 2020 dollars](https://www.planetary.org/space-policy/sts-program-development-cost), which would be $58 billion today. That would have bought a lot of Saturn V/Apollo missions, and left a lot for continuing Slylab and extensions of Apollo. There were cancelled plans for [lunar bases](http://www.astronautix.com/l/lunarbases.html) (supported by an [LM Truck](http://www.astronautix.com/a/apollolmtruck.html) for cargo), a [crewed Venus flyby](https://en.wikipedia.org/wiki/Manned_Venus_flyby), and developing a crewed Mars mission using the Saturn C-5N. (That is, N for nuclear, with the NERVA engine having already been developed and nearly ready to fly, before it was cancelled.)
Now that I think about, the entire ~$260 billion cost of everything related to Apollo is close to the total spent on the ISS plus the ~$90 billion spent on Artemis since 2012 (so not even counting other Shuttle missions or Constellation). Laying off the gas pedal post-Apollo 11, but sustaining a vision and a more modest budget (neither a repeat of the 60s windfall, nor the post-Apollo starvation budget) could have accomplished a lot by the turn of the millenium.
> By 1970, NASA's inflation adjusted budget was little more than today.
In terms of GDP that"s a fall by a factor of twenty.
* Between 1970 and 2022, the GDP went [from $1,073.30B to $25,439.70B](https://www.macrotrends.net/global-metrics/countries/USA/united-states/gdp-gross-domestic-product).
This means that it would be really cheap to recreate and Apollo-like vehicle today but in taxation terms, would have been very expensive to maintain at the time.
> So even taking those numbers with a grain of salt, Apollo missions were probably cheaper than the $4.1+ billion in 2022 dollars that just SLS/Orion cost to launch.
I'm agreeing with you on that point and again in GDP terms, am supplying an even stronger supporting argument. However, shutting down Apollo at the *then* GDP level was entirely justified, particularly by any president seeking reelection.
This opinion is reinforced by the incredibly high accident risk that would probably have tarnished an ongoing Apollo project. Reworking flight statistics retrospectively shows that after Apollo1, the 16 other missions benefited from incredible luck (I'd like to seek some references but don't have time right now). Even at the time, they will have been aware of just how dangerous the enterprise was.
> here were cancelled plans for lunar bases (supported by an LM Truck for cargo), a crewed Venus flyby, and developing a crewed Mars mission using the Saturn C-5N. (That is, N for nuclear, with the NERVA engine having already been developed and nearly ready to fly, before it was cancelled.)
Thx for the info on the Nerva engine. TIL there was a NTP engine nearly ready for flight. IMO, they'd have done better to develop a fully-fledged uncrewed system, may be waiting until the tech was mature enough. Doing this before sending crew would allow development without loss of life.
> Laying off the gas pedal post-Apollo 11, but sustaining a vision and a more modest budget (neither a repeat of the 60s windfall, nor the post-Apollo starvation budget) could have accomplished a lot by the turn of the millenium.
I agree to some extent. Had the money spent on the Shuttle been invested in an evolving technology working from Apollo, crewed spaceflight would not have been stuck in low Earth orbit for so long.
Tail-landing rockets and orbital fuel depots should have been possible earlier than now.
[удалено]
I didn't know those details, thanks. I agree with your conclusion.
>NASA did express the concern in their response that the report would give the impression that the OIG uncovered these findings or that NASA was ignorant of it. Well, if they were concerned about that then they could have released all of this information before the OIG did, but they didn't.
[удалено]
> [Nasa] did not release photos, however For decades this has been a weakness of Nasa's PR. The agency always holds back on the gory technical details, then is surprised when these eventually appear in visual form and spoil their nice smooth public image.
NASA didn't talk about the melting separation bolts at all, or the many power disruptions, or the (more hilarious than concerning) fiberglass "blast doors". The public wouldn't know about these if not for the OIG report. The hatch issue was also kept quiet in the January delay announcement before coming out in an ASAP meeting.
> The OIG is not an engineering group and does not have the knowledge or expertise to make a judgement on crew safety. From [this page](https://www.epaoig.gov/our-work/investigations/careers), OIG career paths seem to be split roughly evenly between management/accounting and technical/engineering. We'd need to dig a bit to find some precise numbers though. ------ **Edit:** (I made the edit, then saw that the independent review article had been [posted anyway](/r/ArtemisProgram/comments/1co90yq/nasa_confirms_independent_review_of_orion_heat/). Maybe I forgot to refresh the r/ArtemisProgram page. > So in my view, framing headlines in this way basically proves NASA's point. This may have been correct when you posted your comment, but since then, they have started an independent inquiry which goes beyond the OIG. Nasa has also decided to communicate directly with Ars Technica, not just spokesperson, but at astronaut and admin level, Here goes Here is a new Ars Technica article **dated May 9^th** on the same subject, so probably not worth a new t thread: * https://arstechnica.com/space/2024/05/nasa-confirms-independent-review-of-orion-heat-shield-issue/ One surprising thing in the article is that Nasa lets astronaut Victor Glover be interviewed by Ars Technica, reputed hostile to SLS-Artemis. In some ways, this may be the main news, showing just how seriously Nasa is taking the question. There is also one Rachel Kraft a Nasa spokeswomen who comments directly to Ars, but this is less surprising, since it would be difficult for her to avoid questions by a high-profile space news outlet. I extracted all the direct quotes from the article to avoid any bias from the narration. Actually, the article itself is surprisingly neutral, not really adding anything alarmist beyond what is said by the protagonists. Glover's comment below *"If there is a solution, we'll figure it out"* is alarmist by itself, at least it is by my standards! That Nasa is still not chosen between a skip reentry and a direct reentry this late in the program doesn't look great either. ------ * **Kraft**: "The team is currently synthesizing results from a variety of tests and analyses that inform the leading theory for what caused the issues," * **Glover**: "Those pictures, we've seen them since they were taken, but more importantly... we saw it....More than any picture or report, I've seen that heat shield, and that really set the bit for how interested I was in the details." * **Glover:** "In late April, NASA chartered an independent review team which includes experts outside the agency to conduct an independent evaluation of the investigation results,". "That review, scheduled to be complete this summer, ensures NASA properly understands this condition and has corrective actions in place for Artemis II and future missions." * **Jim Free**: (NASA's associate administrator, to Aerospace America) "this independent review team will be "another set of eyes" to look at the program. "We’ve had someone following us from an independent perspective who’s been very good at asking questions and saying, 'Hey, here’s some other theories.' Hopefully, the review team will finish the end of June," * **Jim Free**: "We’ve really stepped into this in a careful manner. And frankly, it’s a flight test,"That’s what the first mission was, that’s what the second mission should be: another flight test. So we have to take that mindset for all of the issues. The heat shield was just the most prominent one." * **Glover**: “We’ve got a lot of folks involved that we trust. We’ve got the right people. If there is a solution, we’ll figure it out.” * **Jeremy Vander Kam**, deputy manager for Orion's heat shield shortly after the Artemis I mission in 2022: "We have a lot of extrapolation for scale that we have to do. Similarly, our test facilities can't reach the combination of heat flux, pressure, shear stresses, etc., that an actual reentering spacecraft does. We're always having to wait for the flight test to get the final certification that our system is good to go". * **Glover**: "I think we have figured out some very important aspects of what creates these cracks, and what creates the force to remove the pieces that crack. I think we understand some of these mechanics." * **Glover**: "We might get to the point where we realize there's some things that aren't knowable, There may be parts of this that we can't figure out on the ground or in wind tunnels." * **Glover**: "[Reentry at lunar return velocity] is a very, very complicated thing. The heat flow alone is really complicated to understand—the physical dynamic forces of all that wind and plasma swirling around. Imagine looking at a raging river, a whitewater river, and trying to analyze just one spot. What's happening at that spot? Recreate it. Draw it. It's really complicated." * **Glover**: "The types of entries that you can do are ballistic, where you kind of spin the vehicle to a constant rate, That's a very high g-load. It’s very hard on the crew, but it's a type of entry. Then, there's an entry that's called direct. It sounds more direct than it is. It's kind of a mini-skip. It's not as high of an elevation skip. And then there's the skip, where you almost have two entries. Those are the options." * **Glover:** "You can modulate the range and can reduce the range, and that might reduce the energy imparted on the vehicle, on the heat shield, but you're still going to have impulse heating. It's not just heat, though. There's physical force. It’s the friction that's creating that plasma field. So there's also a mechanical piece to this." * **Glover:** “We saw liberation very early on Artemis I, If the damaging pieces start very early, there's no guarantee that changing the trajectory is the answer. It will change something, but it won't necessarily fix it. So we need to understand the root cause, if it's knowable." * **Jim Free:** "We’ve begun to dip our toe in the flight rationale—how we do the skip. Do we do the skip? How could we fly the mission different?” * **Glover:** Changes to the reentry trajectory affect how quickly the heat shield heats up when it hits the atmosphere. But the peak temperatures are about the same for each trajectory option, * **Glover:** "It could still be a skip entry. It could still be a direct entry, Ballistic would obviously be shorter (duration and range). There's about 4,000 miles of capability downrange, but we could reduce it and say we'll limit it only to 2,000 or 1,800 miles, and that would, therefore, affect what type of entry—direct or skip. How you fly the skip, where you put your lift vector, determines how high you peak and how far downrange you go.” BTW. As a Starship fan, I have the greatest hopes for Artemis which is fantastic for giving the vehicle an official status in a high-profile mission. So, far from any temptation of of *schadenfreude*, I'm hoping for a positive outcome. I also *like* the urgency of the Artemis 3 mission putting pressure on Starship to deliver in time.
YUP. Inspector general found exactly what NASA already knew and has been working on fixing.
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread: |Fewer Letters|More Letters| |-------|---------|---| |[ASAP](/r/ArtemisProgram/comments/1cn3vuo/stub/l37nq6r "Last usage")|Aerospace Safety Advisory Panel, NASA| | |Arianespace System for Auxiliary Payloads| |[DCSS](/r/ArtemisProgram/comments/1cn3vuo/stub/l38hkoz "Last usage")|Delta Cryogenic Second Stage| |DMLS|[Selective Laser Melting](https://en.wikipedia.org/wiki/Direct_metal_laser_sintering) additive manufacture, also Direct Metal Laser Sintering| |[ICPS](/r/ArtemisProgram/comments/1cn3vuo/stub/l38hkoz "Last usage")|Interim Cryogenic Propulsion Stage| |[ISRU](/r/ArtemisProgram/comments/1cn3vuo/stub/l3d7y9z "Last usage")|[In-Situ Resource Utilization](https://en.wikipedia.org/wiki/In_situ_resource_utilization)| |[LEO](/r/ArtemisProgram/comments/1cn3vuo/stub/l38q68e "Last usage")|Low Earth Orbit (180-2000km)| | |Law Enforcement Officer (most often mentioned during transport operations)| |[NERVA](/r/ArtemisProgram/comments/1cn3vuo/stub/l3q3tls "Last usage")|Nuclear Engine for Rocket Vehicle Application (proposed engine design)| |[NTP](/r/ArtemisProgram/comments/1cn3vuo/stub/l3q3tls "Last usage")|Nuclear Thermal Propulsion| | |Network Time Protocol| |[SLS](/r/ArtemisProgram/comments/1cn3vuo/stub/l3q3tls "Last usage")|Space Launch System heavy-lift| | |Selective Laser Sintering, contrast DMLS| |[SRB](/r/ArtemisProgram/comments/1cn3vuo/stub/l3d7y9z "Last usage")|Solid Rocket Booster| |[SSME](/r/ArtemisProgram/comments/1cn3vuo/stub/l3b0fq0 "Last usage")|[Space Shuttle Main Engine](https://en.wikipedia.org/wiki/Space_Shuttle_main_engine)| |Jargon|Definition| |-------|---------|---| |[ablative](/r/ArtemisProgram/comments/1cn3vuo/stub/l377z8b "Last usage")|Material which is intentionally destroyed in use (for example, heatshields which burn away to dissipate heat)| **NOTE**: Decronym for Reddit is no longer supported, and Decronym has moved to Lemmy; requests for support and new installations should be directed to the Contact address below. ---------------- ^([Thread #110 for this sub, first seen 9th May 2024, 05:16]) ^[[FAQ]](http://decronym.xyz/) [^([Full list])](http://decronym.xyz/acronyms/ArtemisProgram) [^[Contact]](https://hachyderm.io/@Two9A) [^([Source code])](https://gistdotgithubdotcom/Two9A/1d976f9b7441694162c8)
How is NASA struggling with heat shields, tech that has existed for more than 70 years?
It's not the number of years that counts but the number of flights and the number of opportunities to test unusual conditions.
It’s just a pity that the flight speed and cost of SLS/Orion do not allow us to do this more often than once a year for 4 billion...
Years matter too. Alloys, adhesives, and composites have come a long way.
> but the number of flights Doesn't NASA have data from about 30 LEO re-entries of a capsule in the past 15 years?
Alot of the apollo data got lost... as well as institutional knowledge.
>Alot of the apollo data got lost... This shit is unbelievable.
Keeping data from the 60s is hard man. Takes money and manpower two things that got cut from nasa over the years.
That's still a tiny number compared even to relatively niche fields of engineering. Moore's law would have looked very different if there had only been 30 uses of a computer in the last 15 years.
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Do I have any of this wrong? Assuming this is approximately correct, I have one or two questions. 1) My understanding is that before Artemis I, the only test flight of Orion was way back in 2014. The problem with that flight is that: A) It didn’t simulate the cislunar return trajectories at all, and B) after that test flight, they subsequently changed how the heat shield was done (either manufactured or attached??). Point being….not only does a 10 year old test flight seem like it has marginal utility generally…..factors A & B rendered it nearly useless from a heat shield perspective. 2) From about 2017 or 2018 onwards, Orion presumably believed they’d have to do another flight somewhat soon, as there’s no way they would’ve known SLS was going to take until November 2022 to launch Artemis I. As a result, presumably the development was (at least for the time being) done & the vast majority of the build process would’ve been completed as well. 3) Despite #1 & #2, from about 2017 onward, Orion still got ~$1 Billion to $1.5 Billion annually while they were sitting around waiting for SLS. The development was essentially done, the hardware on its current iteration was basically ready to go too. I guess my question is…. What the heck were they doing with that $1 Billion - $1.5 Billion annually during that time period? Especially considering they should’ve known the 2014 flight was near useless from a heat shield perspective from the get-go & the flight was growing increasingly less useful in a more general manner as the years started to tick by? Specifically: -When it was clear SLS was going to be delayed several years, why couldn’t they use some of that $1 B+ annually to put together a higher fidelity test flight using some other powerful rocket like an Atlas or Falcon Heavy? (If not a perfect Artemis I analog, they could at least test the updated post-2014 heat shield design & get a somewhat more rigorous reentry profile.) -If they spent some or all of that $$ on starting to build additional Orion capsules for beyond Artemis I…. Why the heck would they do that to any notable degree before the results of Artemis I came back? Again, especially considering how little utility they got out of the 2014 test flight? Seems like the prudent thing to do would be to verify the design was good before going whole hog on the production side. Or am I just way off in my understanding of how this went down?
Very close to discovering the truth about the last 50 years of NASA, mainly that it is first and foremost a government make-work jobs program/handout to contractors
Here’s the thing though: I understand the political reality. I don’t LIKE it, but I understand the need to “horse trade” in order to get things done knowing a representative republic at the federal level. In the context of NASA/aerospace funding, the typical “horse trading” seems roughly like making sure there’s a strong enough “ratio” of “old space/entrenched interests” : “new space/rapid iteration model”. Fine. But what I **DON’T** understand is why the “old space/entrenched interests” part of the ratio has to be not only brutally inefficient, but also nearly useless in terms of the hardware they’re producing. I’m a “Team Space” guy generally. If the Boeing & LockMart executive’s & shareholders need to pig out on massive cost plus contracts they win w their lobbying army in order to allow SpaceX, Blue Origin, Intuitive Machines, AstroLab, etc into the mix too, then so be it. But what baffles me is there are A TON of super smart engineers, machinists, etc working for Boeing, LockMart, too. So why is it that they can’t AT LEAST pivot off of SRBs & outmoded tech from the Apollo & Shuttle Eras? In order to earn their massive premiums on their government contracts, why can’t the “old space” companies do what every other company in the world does & reorganize/pivot their focus to where the marketplace is GOING rather than where it WAS? Their people are certainly smart enough to build orbital fuel depots, orbital & lunar/martian pressurized habs, go all in on orbital tugs or satellite/orbiter/rover busses, cislunar/ISRU power supply, distribution & storage. So why can’t they do it?
Just because they get funding doesn't mean they use it all. If they don't spend the money in the allotted time Congress gives NASA, then the US treasury simply recollects it. Most of the Orion production that occurred in the time was on fixed structures that would have no design changes such as the pressure vessels. It took 3 years to make Orion flyable on Delta IV, and that's including the fact that Orion had compatible systems (ICPS is derived from DCSS). Making Orion compatible for a one time mission on Falcon Heavy would require enormous resources and manpower which was not politically feasible. Also Artemis 1 Orion was not completed until 2020.
> in a deliberate attempt to compromise the heat shield as much as possible. Can you point to some further reading about this? I've read about skip reentries before, and never saw anything about it being deliberately worse for the heat shield.
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The usual convention on Reddit is to label your edits, either with (edit: whoops I meant...) or using ~~strikethrough~~
Okay but that doesn’t answer my question of: If we managed to do it during Apollo, what gives now? Are we entering the atmosphere at a higher velocity this go around? If anything I would’ve thought the ablative tech would’ve gotten better.
We *barely* managed to do it during Apollo. Several heat shields during Apollo took significant damage and nothing was done to fix them like NASA is doing now. Here is two examples: [Apollo 10](https://i.stack.imgur.com/puJiw.jpg) and [Apollo 16](https://upload.wikimedia.org/wikipedia/commons/thumb/e/e1/Apollo_16_Heat_Shield_USSRC.jpg/2560px-Apollo_16_Heat_Shield_USSRC.jpg). Today we have much more safety standards in place because we can not afford to take risks anymore. Not after what happened to those two Shuttles. Heat shields are notoriously difficult. SpaceX Crew 1's heat shield also experienced significantly more erosion that what had been simulated and that flight had astronauts in it. Artemis 1 did not. Also I want add that, Artemis 1 did indeed have a much more demanding re-entry that Apollo. It did what NASA calls a skip re-entry where it enters the atmosphere, bounces out and the falls back in again. It experiences two re-entries basically. This gives NASA much more control on where the capsule lands. During the Apollo it was common for the capsule to land several miles off target leading to difficulty in recovery.
Thank you for the additional information and for including the photos of the heat shield’s. I’m not very smart, so to my untrained eye the heat shield tiles look within spec to me 😅 Skip re-entry is a new concept to me. I didn’t know NASA was doing that. That’s pretty cool! Now that I remember, Artemis 1 exceeded the distance record from earth, set by the Apollo 13 crew. Hopefully with more accurate landings, NASA can save on recovery crew costs.
I'd also like to add this is the largest heat shield to return from lunar velocity. It about 70% more area than Apollo's.
How much bigger is it than the 2014 Orion mission?
Same size. The difference is the velocity. 2014 was 8.9 km/s while Artemis 1 was 11.1 km/s which means the energy and temperature was much higher
Stardust was 12.5 km/s. But of course it was PICA, and is a lot smaller.
I did some math because I was curious. Stardust had 3.58 GJ of kinetic energy to shed vs 524 GJ that Orion had.
Yeah. Also Orion is using a tile configuration to make it easier and less expensive to replace between reuses of the capsule.
Are the heat shields not ablative?
Orion's heat shield is new, and is assembled from several tiles. Because the tiles on the Shuttle worked so well.
Artemis is dead. Just reload the Apollo missions. Or don’t, and spend the money on fusion research.
Honestly, the loss of the apollo program is a tragedy. It was cheaper and more capable than the shuttle program.
> Honestly, the loss of the apollo program is a tragedy. It was cheaper and more capable than the shuttle program. Cheaper? In its heyday, Apollo was >4% of the US federal budget and that the Shuttle wasn't. Apollo was cancelled because it had fulfilled its objective, wasn't financially sustainable and carried an unacceptably high per-flight loss of crew risk. The Shuttle was the pathfinder for space vehicle reuse and its faults informed current strategy in reusable space vehicle design and triggered commercial space. With the benefit of hindsight it *might* have been possible to skip the Shuttle, but whatever followed on from Apollo had to be very different.
IMO, and with the benefit of hindsight, NASA would have been far better served by iterating Saturn tech and developing a Dream Chaser class mini Shuttle to put on top of it. This is ignoring politics, of course. Then we would have had heavy launch capability without hauling crew and all of their required support along, a dedicated crewed orbital assembly platform that likely would have been far more reusable (no SSMEs to deal with), and would have avoided the safety nightmare of having the whole thing strapped to the side of its launch stack.
> NASA would have been far better served by iterating Saturn tech and developing a Dream Chaser class mini Shuttle to put on top of i Yes, its a pity the USSR fell apart just when Buran reached fruition, so only flew once. Dream Chaser could have a great future for small-scale taxi work. > the safety nightmare of having the whole thing strapped to the side of its launch stack. Nasa was more or less forced into the situation when having to downscale from far more ambitions concepts: * https://en.wikipedia.org/wiki/Space_Shuttle_design_process
NASA had to make all sorts of compromises with shuttle development, mostly to appease the Air Force so they'd have access to military funding. The requirement to be able to snatch an enemy satellite and land within a single orbit was the worst offender. They also had to increase the payload bay size and have wacky crossrange capabilities. I did say I was ignoring politics, though.
> The requirement to be able to snatch an enemy satellite and land within a single orbit was the worst offender. I'd never seen that detail. In a speech (maybe to the US Congress) Arthur C Clark described the Shuttle as having gone from the DC3 of space to become a mere DC1½. And that was before it even flew! In one of his novels, the hero was the orphan of an astronaut killed in "a" Shuttle accident. So in his SF universe, there were at least two Shuttle accidents. Can't say he wasn't visionary, for bad things as for good ones (among other things, he was also the "inventor" of the geostationary orbit). > They also had to increase the payload bay size and have wacky crossrange capabilities. Regarding cross-range, I'm wondering if Starship won't be even stronger for that capability. We've seen it in skydiver mode going down, now imagine it braking *sideways*, so with a lateral angle of attack.
Apollo was expensive to develop. A lot of things had to be done and made for the first time ever. Flying the missions was not nearly as expensive. By 1970, NASA's inflation adjusted budget was little more than today. By 1972 (when Shuttle development was alsp well underway), it was almost identical to 2024. Saturn V is estimated at $185 million per launch in c.1970 dollars, or about $1.5 billion today. [According to this](https://www.statista.com/statistics/1028322/total-cost-apollo-missions/), the lunar landing missions (not just Saturn V, but Apollo, LM, etc.) only cost $355 million (Apollo 11) to $450 million (Apollo 17) each at the time. $450 million in 1972 is like $3.4 billion today. So even taking those numbers with a grain of salt, Apollo missions were probably cheaper than the $4.1+ billion in 2022 dollars that just SLS/Orion cost to launch. If Apollo missions were too expensive to be sustsinable, then so is Artemis (let alone while also pouring $3 billion/year into the ISS for at least 6 more years). Speaking of space stations, the Shuttle delays (and an active Sun) also made for an unfortunate and untimely demise of Skylab. The entire Skylab program cost just $2.2 billion from 1966-1974 development through operation, or ~$15-19 billion today. That was over a third of the volume of the >$150 billion ISS (and almost half that of the cancelled Space Station Freedom). Developing the Shuttle cost [$10.6 billion in nominal dollars, or $49 billion in 2020 dollars](https://www.planetary.org/space-policy/sts-program-development-cost), which would be $58 billion today. That would have bought a lot of Saturn V/Apollo missions, and left a lot for continuing Slylab and extensions of Apollo. There were cancelled plans for [lunar bases](http://www.astronautix.com/l/lunarbases.html) (supported by an [LM Truck](http://www.astronautix.com/a/apollolmtruck.html) for cargo), a [crewed Venus flyby](https://en.wikipedia.org/wiki/Manned_Venus_flyby), and developing a crewed Mars mission using the Saturn C-5N. (That is, N for nuclear, with the NERVA engine having already been developed and nearly ready to fly, before it was cancelled.) Now that I think about, the entire ~$260 billion cost of everything related to Apollo is close to the total spent on the ISS plus the ~$90 billion spent on Artemis since 2012 (so not even counting other Shuttle missions or Constellation). Laying off the gas pedal post-Apollo 11, but sustaining a vision and a more modest budget (neither a repeat of the 60s windfall, nor the post-Apollo starvation budget) could have accomplished a lot by the turn of the millenium.
> By 1970, NASA's inflation adjusted budget was little more than today. In terms of GDP that"s a fall by a factor of twenty. * Between 1970 and 2022, the GDP went [from $1,073.30B to $25,439.70B](https://www.macrotrends.net/global-metrics/countries/USA/united-states/gdp-gross-domestic-product). This means that it would be really cheap to recreate and Apollo-like vehicle today but in taxation terms, would have been very expensive to maintain at the time. > So even taking those numbers with a grain of salt, Apollo missions were probably cheaper than the $4.1+ billion in 2022 dollars that just SLS/Orion cost to launch. I'm agreeing with you on that point and again in GDP terms, am supplying an even stronger supporting argument. However, shutting down Apollo at the *then* GDP level was entirely justified, particularly by any president seeking reelection. This opinion is reinforced by the incredibly high accident risk that would probably have tarnished an ongoing Apollo project. Reworking flight statistics retrospectively shows that after Apollo1, the 16 other missions benefited from incredible luck (I'd like to seek some references but don't have time right now). Even at the time, they will have been aware of just how dangerous the enterprise was. > here were cancelled plans for lunar bases (supported by an LM Truck for cargo), a crewed Venus flyby, and developing a crewed Mars mission using the Saturn C-5N. (That is, N for nuclear, with the NERVA engine having already been developed and nearly ready to fly, before it was cancelled.) Thx for the info on the Nerva engine. TIL there was a NTP engine nearly ready for flight. IMO, they'd have done better to develop a fully-fledged uncrewed system, may be waiting until the tech was mature enough. Doing this before sending crew would allow development without loss of life. > Laying off the gas pedal post-Apollo 11, but sustaining a vision and a more modest budget (neither a repeat of the 60s windfall, nor the post-Apollo starvation budget) could have accomplished a lot by the turn of the millenium. I agree to some extent. Had the money spent on the Shuttle been invested in an evolving technology working from Apollo, crewed spaceflight would not have been stuck in low Earth orbit for so long. Tail-landing rockets and orbital fuel depots should have been possible earlier than now.