mxaxai wrote:

The main problem is manufacturing cost and complexity, and since politics decided that this was acceptable, the RS-25 is an obvious choice.

Obvious and only choice…

Plan to seal hydrogen leak with helium did not work. Options being discussed.

Trying plan A again… allow hydrogen quick disconnect to warm up, then chill it down.

LOX tank is full. Hydrogen at 10 percent. ICPS tanking preps underway.

Second warm up of hydrogen quick disconnect did not fix leak.

Thanks for the continuous updates.

At what point do they scrub? When there's not enough time to fix the hydrogen leak before the launch window is over?

Launch team has recommended a scrub - no decision yet.

Scrubbed for today.

Scrub today, due to inability to heal the hydrogen leak in the core stage and umbilical. That's a major disappointment for them.

Looks like the launch is scrubbed

Avatar2go wrote:

Scrub today, due to inability to heal the hydrogen leak in the core stage and umbilical. That's a major disappointment for them.

Hydrogen leaks, unfortunately, were not unexpected. Shuttle had numerous issues with LH2 leaks.

Makes me wonder how similar are the shuttle and SLS tail service mast quick disconnect designs?

zanl188 wrote:

Hydrogen leaks, unfortunately, were not unexpected. Shuttle had numerous issues with LH2 leaks.

Makes me wonder how similar are the shuttle and SLS tail service mast quick disconnect designs?

From discussions with people at NASA, they are very similar. The issue is that the behavior is highly dependent on past history and environmental factors. You might get it to work on one fill, but then doesn't work on the next fill, after thermal cycling.

A result of needing it to be a quick disconnect umbilical, combined with the smallest known atom, combined with extreme temperature swings.

Just a side question.
Why do you say smallest KNOWN atom?
Even if you hypothesize by absurd a smaller one would exist it will then not fit the definition of atom anymore...

Aquila3 wrote:

Just a side question.
Why do you say smallest KNOWN atom?
Even if you hypothesize by absurd a smaller one would exist it will then not fit the definition of atom anymore...

AFAIK the helium atom is a bit smaller than the hydrogen one, due to the larger positive charge pulling in those electrons. But yet H2 is the smallest molecule. To date there exists no container that can store H2 without leakage. The molecule just wanders through any material... sloooowly...

LH2 fill line saw a pressure spike earlier today. Unknown if it’s related to the new leak.

Evaluating options to replace and test the “soft goods” in the LH2 quick disconnect.

No launch attempt Monday.

Maybe, Starship flies to space before SLS does... I read suggestions that it would be either Monday or October, the next SLS launch attempt.

I'm so looking forward to the SLS launch - because I've never ever watched a live Shuttle launch. And SLS would at least provide some of the good, old Shuttle aesthetics...

To clarify the questions above, as I said the combination of the quick disconnect seal, the properties of liquid hydrogen, and the extreme temperature swing the seal undergoes, make it a difficult seal to maintain. That should be readily understandable to everyone.

I don't know the relative relation to liquid helium, but also know of no application that requires or flows LHE through quick disconnects at the volume of SLS requires for LH2. As far as the "known atom", I meant that there is not a propellant that is more difficult to work with in terms of leaks. I think my meaning was apparent.

From the NASA Artemis conference today:

1. There was an inadvertent pressure spike during LH2 chilldown, that raised the line pressure from 20 to 60 psi, due to an error in valve control. It's suspected this might have dislodged or damaged the soft goods in the umbilical seal, but that is not confirmed.

2. The magnitude of the leak was very large, exceeding the allowable limit by several times. Much larger than previously seen, and indicative of soft seal damage, rather than thermal equilibrium.

3. No possibility of launch this period. The FTS restrictions will require a rollback to the VAB, unless an exception is granted, which is doubtful. They may attempt to replace the seal at the pad, and then test under cryo conditions, before rolling back.

4. They are working the fault tree to be sure they understand what happened, and that will take some time. So no prediction for next launch attempt. Could be in either of the next two launch windows, in late September and middle October.

Here is a good series of Twitter posts from someone in the NASA cubesat program, with good information on the Artemis secondary payload cubesat status.

Quick summary, they were designed for a battery charge of up to one year before launch. Five of the ten can be recharged in place, and they are ok. The five that cannot, have solar panels and will recharge after launch. The main penalty is time in flight before they have sufficient power. For a few, this time could cause them to miss their planned trajectories. But all the teams are working on contingencies.

Notably the teams do not fault NASA, and view this as an exciting future capability to develop, being able to launch large numbers of low cost cubesats on the largest launch vehicle.

https://twitter.com/hardgrove/status/15 ... H9eiw&s=19

Here is a Twitter thread of appreciation for the media, from one of the astronauts who works with them. She rightly points out that most of the media work really hard to bring information about NASA to the public, without bias or negative commentary.

https://twitter.com/AstroAnnimal/status ... 5057505282

Avatar2go wrote:

Here is a Twitter thread of appreciation for the media, from one of the astronauts who works with them. She rightly points out that most of the media work really hard to bring information about NASA to the public, without bias or negative commentary.

https://twitter.com/AstroAnnimal/status ... 5057505282

In other words, the media is a cost free cheering squad.
I believe that the Artemis should be melted down for what ever scrap metal value it has.
NASA needs to get out of the rocket ship manufacturing business.
The Space Shuttle was a dog and so is Artemis.

Vintage wrote:

In other words, the media is a cost free cheering squad. I believe that the Artemis should be melted down for what ever scrap metal value it has.
NASA needs to get out of the rocket ship manufacturing business. The Space Shuttle was a dog and so is Artemis.

Fortunately the people who are knowledgeable and make the decisions, have a better opinion.

The media reflects public interest in the program, as also indicated by the crowds. A few outlets are exceptionally critical of NASA, as you obviously are as well, but they are decidedly in the minority.

Avatar2go wrote:

Fortunately the people who are knowledgeable and make the decisions, have a better opinion.

The media reflects public interest in the program, as also indicated by the crowds. A few outlets are exceptionally critical of NASA, as you obviously are as well, but they are decidedly in the minority.

I remember the Space Shuttle fanatics back in the day - I was pretty neutral.
Looking back on it, everything the Space did could have been done better and cheaper than the Shuttle.

It's the same with Artemis, the Starship can do it all dependably and more for far less money.
And there are a half a dozen others in the wings.

Vintage wrote:

I remember the Space Shuttle fanatics back in the day - I was pretty neutral.
Looking back on it, everything the Space did could have been done better and cheaper than the Shuttle.

It's the same with Artemis, the Starship can do it all dependably and more for far less money.
And there are a half a dozen others in the wings.

This is a common fallacy, but has no basis in fact. The Shuttle was designed, and was a product of, the Apollo era. There was only a fledgling market for commercial space at that time. Nothing whatever on the scale of SpaceX or ULA today. Shuttle was the available technology then, and it did a great job, within it's era and scope.

Second, Starship is a prototype that has potential, if several technical capabilities can be developed, that don't exist today. Also if the market continues to expand, such that it can become economical. Neither of those things are assured at present.

Thus the same issue exists for comparison to Artemis. Starship and SLS are designed for different missions, and while Artemis is a fully formed platform ready to launch, Starship is still a prototype in development, with considerable uncertainty ahead.

I hope that Starship reaches it's potential, it would be a valuable addition to the US space fleet, along with the others currently in development. But it's not there today.

Vintage wrote:

Looking back on it, everything the Space did could have been done better and cheaper than the Shuttle.

And where do you think all the current knowledge came from so that we can look back at the past? I find your statement sad and fairly uninformed.

Here are some of the examples what various orbiters delivered over time:
Compton Gamma Ray Observatory (CGRO) 37,000 lbs
Chandra X-ray Observatory 50,222 lbs (whole payload)
Hubble Space Telescope 24,490 lbs, launch plus 5 servicing missions
ISS - Unity (Node 1) 26,224 lbs
ISS - Destiny (US Laboratory) 32,000 lbs
ISS - Harmony (Node 2) 31,500 lbs
ISS - JEM Pressurized Module (JEM-PM) 35,100 lbs
ISS - Tranquility (Node 3) 42,000 lbs
ISS - trusses and solar arrays (servicing done using robotic arms was only possible using orbiters)
Tracking and data relay satellites
Spacelab - 22 missions
Spitzer Space Telescope
Galileo
Magellan
Ulysses
Mir Docking Module

And which other vehicle could bring back to Earth up to 35,000 lbs of payload? I mean since you are looking back anyway?

BEG2IAH wrote:

Vintage wrote:

Looking back on it, everything the Space did could have been done better and cheaper than the Shuttle.

And where do you think all the current knowledge came from so that we can look back at the past? I find your statement sad and fairly uninformed.

Here are some of the examples what various orbiters delivered over time:
Compton Gamma Ray Observatory (CGRO) 37,000 lbs
Chandra X-ray Observatory 50,222 lbs (whole payload)
Hubble Space Telescope 24,490 lbs, launch plus 5 servicing missions
ISS - Unity (Node 1) 26,224 lbs
ISS - Destiny (US Laboratory) 32,000 lbs
ISS - Harmony (Node 2) 31,500 lbs
ISS - JEM Pressurized Module (JEM-PM) 35,100 lbs
ISS - Tranquility (Node 3) 42,000 lbs
ISS - trusses and solar arrays (servicing done using robotic arms was only possible using orbiters)
Tracking and data relay satellites
Spacelab - 22 missions
Spitzer Space Telescope
Galileo
Magellan
Ulysses
Mir Docking Module

And which other vehicle could bring back to Earth up to 35,000 lbs of payload? I mean since you are looking back anyway?

Which other vehicle?

I can't tell you that because nothing else was built with the 209 Billion dollars the Space Shuttle program ate; (those were 1980s billions, not 21st century billions). Rocket development essentially stalled for 30 or so years.

Avatar2go wrote:

The current RSRMV SRB has only marginal improvements over the shuttle era, because of the need to use up the existing inventory. The follow on BOLE, which is based on the OmegA, is significantly improved. It has composite casing, which means it carries much more propellant for the same weight, with lower cost. The propellant is a modern HTPB formulation, that is tuned to modulate output, so as to more efficiently utilize the RS-25 (no more throttle back at Max-Q). It has an improved all-electric motor section which greatly increases both thrust and vectoring control (no more hydrazine). The nozzle assembly has a much greater expansion ratio and resultant specific impulse. All new avionics as well.

I don't understand this.

Math says max effecency is to carry the highest ISP fuel the highest, and burn the lowest ISP fuel as close to the ground as possible. Therefore the LOX+H engines *should* be the ones to throttle back, and the SRBs should be at max power.

Avatar2go wrote:

The $4B launch cost is disputed by NASA, and in any case is only the first development & test flight cost. NASA estimates the initial true incremental cost at $2B, with that decreasing to around $1B as the program reaches maturity.

Yes, I see where you wrote "first development and test flight costs". But the OIG says they've spent $25B so far.

Even better, project total costs over some reasonable number of launches. " NASA's spending on its Artemis program, which aims to establish a sustainable human presence on and around the moon by the end of the decade, is projected to reach a total of $93 billion by 2025, according to a new audit by the NASA Office of Inspector General (OIG)." -- https://www.space.com/nasa-artemis-moon ... llion-2025.

kitplane01 wrote:

Math says max efficency is to carry the highest ISP fuel the highest, and burn the lowest ISP fuel as close to the ground as possible. Therefore the LOX+H engines *should* be the ones to throttle back, and the SRBs should be at max power.

The efficiency of the stack is the combined efficiency of the engines. For traditional staging, you fire all one, then all the other, they don't overlap. With Shuttle/SLS, they fire simulataneously so you can optimize the thrust trace for the combination. The Shuttle used throttling of both at Max Q, because the SRB was unable to absorb the entire throttle. For BOLE, the design can be optimized to absorb the throttle. This results in higher efficiency of the stack. Here is an article that is explains what was done in optimizing the design:

https://www.nasaspaceflight.com/2021/07/sls-bole-srbs/

Even better, project total costs over some reasonable number of launches. " NASA's spending on its Artemis program, which aims to establish a sustainable human presence on and around the moon by the end of the decade, is projected to reach a total of $93 billion by 2025, according to a new audit by the NASA Office of Inspector General (OIG)." -

You have to consider what is covered by the $93B. It includes all development, ground systems, telecommunications, control room, crawler, mobile launchers, and other indirect support costs. In terms of direct flight costs, it includes the Orions, the core stages, the boosters, the landers, the rovers, the spacesuits, the Gateway station, the CLIPS missions, and all the lunar robotics, cubesats, and satellites, through the year 2030.

The $93B is a little more that one third the cost of the Apollo program at $250B, but Artemis is a far more complex and robust exploration program than Apollo.

This is where the media reporting often fails, and even the OIG reports can be misleading. And why they are disputed by NASA. The OIG finds and accounts every cost that can be feasibly charged to Artemis. It's fine to do that to determine an upper bound on total program cost. But if you look at the incremental cost to actually launch a mission, it's far less.

There's an analogy for the F-35, which is often described as the most expensive fighter program ever, at $1.6T. But the incremental flyaway cost of an F-35 is actually lower than other recent fighters, at between $80M and $100M. So it's misleading to characterize it that way.

There's no question that SLS launches are expensive. But SLS has the highest characteristic energy ever produced, which means it can do direct missions to Mars and well beyond. For shorter lunar missions, it can carry heavy lunar payloads beneath Orion, and will for the later missions. And at least for now, is the only human rated deep space launcher or vehicle.

As with all rocket programs, cost depends on cadence, and will decline with maturity. NASA will start at 1 per year, moving to 2 per year, and then perhaps to 3 per year. But there are also many lunar payloads that don't require Artemis, and can use other commercial launchers, so NASA will utilize those as well.

The Artemis program / SLS has access to 16 RS-25 engines from the shuttles. Which means there will only be 4 SLS launches. Or am I wrong? Will there be additional RS-25 engines produced?

JetBuddy wrote:

The Artemis program / SLS has access to 16 RS-25 engines from the shuttles. Which means there will only be 4 SLS launches. Or am I wrong? Will there be additional RS-25 engines produced?

Yes, in the refurbishment contract for the 16 shuttle engines, NASA included a request for Aerojet to restart the production line with new tooling and manufacturing methods, with the option to produce up to 6 new non-reusable & upgraded engines, for certification, testing and eventual flight.

Then in a separate contract, NASA expanded the order from 6 to 18 additional engines, with further performance and manufacturing improvements. There is expected to be a third add-on order eventually, for a future third generation engine.

The NASA policy is that 2 spare engines must be on-hand for contingencies in every launch. So the new engines will need to be ready by Artemis 4. They are pretty far ahead of schedule on that.

Vintage wrote:

Looking back on it, everything the Space did could have been done better and cheaper than the Shuttle.

Probably, but would have Congress approves funding for developing the ho-hum rockets? NASA was and still is a political entity.

From the technical side, you really don't know the good and the bad of the Shuttle until you try.

Elon was still a lad in South Africa when the Shutle first flew.

Who knows? May be the two biggest contributions of the Shuttles are the Hubble and putting a spark in the brain of young Elon.

bt

The shuttle was designed based on risk assessment methods and assumptions that were from the Apollo era, and significantly underestimated the true risks.
Apollo survived that because the number of flights were not sufficient to manifest the risk in terms of fatalities (apart from Apollo 1 which was a ground accident). Although there were some close calls (Apollo 13).

The shuttle program had sufficient flights for the risk to manifest in both close calls and fatalities. As a result, the assessment methods changed, and with improvement the results gradually converged on the true risks. Those are the methods in use today.

Neither Shuttle nor Apollo would be acceptable designs today. This is the fallacy in the claims that Artemis is based on 50 year-old technology. Almost everything has undergone design changes to improve performance & meet the current safety standards.

Avatar2go wrote:

JetBuddy wrote:

The Artemis program / SLS has access to 16 RS-25 engines from the shuttles. Which means there will only be 4 SLS launches. Or am I wrong? Will there be additional RS-25 engines produced?

Yes, in the refurbishment contract for the 16 shuttle engines, NASA included a request for Aerojet to restart the production line with new tooling and manufacturing methods
...
So the new engines will need to be ready by Artemis 4. They are pretty far ahead of schedule on that.

Good question-- I've also wondered about using what I think of as SSME stock as expendable-- and good answer... thanks!

Avatar2go wrote:

JetBuddy wrote:

The Artemis program / SLS has access to 16 RS-25 engines from the shuttles. Which means there will only be 4 SLS launches. Or am I wrong? Will there be additional RS-25 engines produced?

Yes, in the refurbishment contract for the 16 shuttle engines, NASA included a request for Aerojet to restart the production line with new tooling and manufacturing methods, with the option to produce up to 6 new non-reusable & upgraded engines, for certification, testing and eventual flight.

Then in a separate contract, NASA expanded the order from 6 to 18 additional engines, with further performance and manufacturing improvements. There is expected to be a third add-on order eventually, for a future third generation engine.

The NASA policy is that 2 spare engines must be on-hand for contingencies in every launch. So the new engines will need to be ready by Artemis 4. They are pretty far ahead of schedule on that.

Thank you for the thorough explanation, I value your contribution to our space discussions!

Avatar2go wrote:

kitplane01 wrote:

Math says max efficency is to carry the highest ISP fuel the highest, and burn the lowest ISP fuel as close to the ground as possible. Therefore the LOX+H engines *should* be the ones to throttle back, and the SRBs should be at max power.

The efficiency of the stack is the combined efficiency of the engines. For traditional staging, you fire all one, then all the other, they don't overlap. With Shuttle/SLS, they fire simulataneously so you can optimize the thrust trace for the combination. The Shuttle used throttling of both at Max Q, because the SRB was unable to absorb the entire throttle. For BOLE, the design can be optimized to absorb the throttle. This results in higher efficiency of the stack. Here is an article that is explains what was done in optimizing the design:

https://www.nasaspaceflight.com/2021/07/sls-bole-srbs/

That was an interesting article. I read it twice (thought I might have missed something). But it doesn't explain why they would run the higher ISP engine, while reducing thrust on the lower ISP engine. I'm sure that's bad from a math point of view, but I imagine they have some reason. I just wonder what it is.

They write about varying throttle to reduce both dynamic loads (max-Q) and structural loads. I wonder if the reason some engineering/structural thing.

Avatar2go wrote:

Even better, project total costs over some reasonable number of launches. " NASA's spending on its Artemis program, which aims to establish a sustainable human presence on and around the moon by the end of the decade, is projected to reach a total of $93 billion by 2025, according to a new audit by the NASA Office of Inspector General (OIG)." -

You have to consider what is covered by the $93B. It includes all development, ground systems, telecommunications, control room, crawler, mobile launchers, and other indirect support costs. In terms of direct flight costs, it includes the Orions, the core stages, the boosters, the landers, the rovers, the spacesuits, the Gateway station, the CLIPS missions, and all the lunar robotics, cubesats, and satellites, through the year 2030.

The $93B is a little more that one third the cost of the Apollo program at $250B, but Artemis is a far more complex and robust exploration program than Apollo.

This is where the media reporting often fails, and even the OIG reports can be misleading. And why they are disputed by NASA. The OIG finds and accounts every cost that can be feasibly charged to Artemis. It's fine to do that to determine an upper bound on total program cost. But if you look at the incremental cost to actually launch a mission, it's far less.

There's an analogy for the F-35, which is often described as the most expensive fighter program ever, at $1.6T. But the incremental flyaway cost of an F-35 is actually lower than other recent fighters, at between $80M and $100M. So it's misleading to characterize it that way.

First, it's all the costs through 2025, not 2030.

Second, I politely disagree with how you do math. For the F-35, development costs *should* count. For Artimis, development costs *should* count. And if it's purpose is to put humans on the moon, then the cost of a lunar-rated space suit also counts. Even though NASA plans to spend an astronimiclly large amount on the suits, they are a small cost for the program as a whole.

I really wonder if the $93B (and more coming) costs of Artimis could have gotten better science by spending it elsewhere.

kitplane01 wrote:

I really wonder if the $93B (and more coming) costs of Artemis could have gotten better science by spending it elsewhere.

For the cynical people: Artemis is just a giant and rather ineffective job program - perfectly designed to please certain voters in certain counties where certain aerospace companies own certain factories...

For the less cynical ones:

That's your multi-armed bandit problem.

https://en.wikipedia.org/wiki/Multi-armed_bandit

Imagine you're a research foundation. You're given 50 proposals on which technologies to research, and you have a finite amount of money to spend. You have zero knowledge about which project would be the most rewarding one - because every sane project leader will say that his project is the most valuable one. You do not know how long they are going to take. And you do not know which project would yield some usable, trustworthy knowledge after a short "test run", which would allow you to re-allocate money based on that new information.

Basically, it's the only problem we have. Everything else is just a matter resource allocation.

kitplane01 wrote:

Second, I politely disagree with how you do math. For the F-35, development costs *should* count. For Artemis, development costs *should* count. And if it's purpose is to put humans on the moon, then the cost of a lunar-rated space suit also counts. Even though NASA plans to spend an astronomically large amount on the suits, they are a small cost for the program as a whole.

No one is disputing that development costs "should" count. The point was that for aircraft, the flyaway cost is also an important metric. Just as the incremental cost is an important metric for rockets. And that Artemis is paying for a ton of assets besides the rocket.

I really wonder if the $93B (and more coming) costs of Artemis could have gotten better science by spending it elsewhere.

We can never know the answer (the path not taken) but Musk is saying Starship will require $10B in investment, and that is increasingly looking to be a conservative estimate. And that is for one vehicle, attaining LEO, without the other assets that Artemis provides, and without human rating.

I think the argument of "what could have been done" is one of the fallacies surrounding NASA & the Artemis program. There is value in maintaining proficiency at NASA and in the "old-space" vendors. The idea that all that work could have been turned over to one or two "new-space" vendors, is absurd. It wouldn't be possible even today, much less a decade ago.

I'm actually all for "new-space" and wish them every success. I also believe that NASA will continue to hand over programs to the commercial sector, as they can demonstrate that two robust responses become possible. That has been the pattern and I'm sure it will continue. Eventually the old and new will blend into a competitive market, that has been fostered and supported by NASA. Who will remain in the business of exploration, which is their mission.

But the premise that this could be done today, or years ago, is just not valid. The people who claim that, don't understand the financial & engineering contributions that NASA is making to the new-space programs. They are very significant.

NASA has decided to replace the Artemis hydrogen umbilical seal on the launch pad, where they can then test it by flowing LH2.  They will enclose & condition it temporarily from the elements for the repair.  Reports are that they are developing this as a permanent capability, for future launches.

NASA reportedly is also preparing a case to present to Range Safety for a late September launch date, to avoid a rollback.  I continue to believe that is unlikely, but we'll have to see.

https://blogs.nasa.gov/artemis/

Avatar2go wrote:

kitplane01 wrote:

Second, I politely disagree with how you do math. For the F-35, development costs *should* count. For Artemis, development costs *should* count. And if it's purpose is to put humans on the moon, then the cost of a lunar-rated space suit also counts. Even though NASA plans to spend an astronomically large amount on the suits, they are a small cost for the program as a whole.

No one is disputing that development costs "should" count. The point was that for aircraft, the flyaway cost is also an important metric. Just as the incremental cost is an important metric for rockets. And that Artemis is paying for a ton of assets besides the rocket.

I really wonder if the $93B (and more coming) costs of Artemis could have gotten better science by spending it elsewhere.

We can never know the answer (the path not taken) but Musk is saying Starship will require $10B in investment, and that is increasingly looking to be a conservative estimate. And that is for one vehicle, attaining LEO, without the other assets that Artemis provides, and without human rating.

I think the argument of "what could have been done" is one of the fallacies surrounding NASA & the Artemis program. There is value in maintaining proficiency at NASA and in the "old-space" vendors. The idea that all that work could have been turned over to one or two "new-space" vendors, is absurd. It wouldn't be possible even today, much less a decade ago.

I'm actually all for "new-space" and wish them every success. I also believe that NASA will continue to hand over programs to the commercial sector, as they can demonstrate that two robust responses become possible. That has been the pattern and I'm sure it will continue. Eventually the old and new will blend into a competitive market, that has been fostered and supported by NASA. Who will remain in the business of exploration, which is their mission.

But the premise that this could be done today, or years ago, is just not valid. The people who claim that, don't understand the financial & engineering contributions that NASA is making to the new-space programs. They are very significant.

No one I've met knows the future ... but I think one can make a strong argument that for NASAs launch system "burn it to the ground and contract everything to ULA/SpaceX" would be exactly right. I'd wonder if you would get twice the speed at half the cost.

SLS (which is the thing making the news now) was supposed to cost $10B, incremental cost $0.5B per launch, and require 7 years. It's now at $25B, $2B per launch, and 12 years. I think SpaceX could do better, and I *hope* ULA could.

SpaceX's Starship is to be fully reusable, and no one thinks they spent $25B to develop it. Also, arguably it began serious development in 2017, and 5 years later they have a prototype.

Question: Would you rather have Starship with it's developmetn costs and timeline, or SLS with it's development costs and timeline?

kitplane01 wrote:

No one I've met knows the future ... but I think one can make a strong argument that for NASAs launch system "burn it to the ground and contract everything to ULA/SpaceX" would be exactly right. I'd wonder if you would get twice the speed at half the cost.

I believe this argument is largely based on misunderstanding of the industry. At the time SLS was conceived, there was no commercial entity that could have undertaken the project. As I mentioned, it's a fallacy that has taken root amongst Musk supporters, but Musk himself does not make this claim.

SLS (which is the thing making the news now) was supposed to cost $10B, incremental cost $0.5B per launch, and require 7 years. It's now at $25B, $2B per launch, and 12 years. I think SpaceX could do better, and I *hope* ULA could.

These are fair criticisms, apart from the fallacy regarding SpaceX/ULA capability. But if you tell the whole story, the program changed direction with each administration, except the current one. And was consistently funded at $2B - $3B per year for most of its development life. Of the $93B you quoted, the majority occurs in the last 3 years after launch operations have begun.

The issue that arises with flat funding, is that you extend and inflate labor and facility costs, in return for a predictable budget. If there are delays, which there always are in all space programs, those costs accumulate because you can't divest expertise or shut down buildings during the delay. Even if the delays are non-technical, like COVID & storm damage.

The alternative is to open the spigot to resolve any problem or delay. That was the strategy in Apollo, with resultant high costs. Shuttle was an intermediate case, so NASA has now run the gamut of funding levels, high to moderate to low. But all had delays and all had budget overruns. Artemis has had the lowest net cost of the three.

Lastly, the amount spent thus far includes advance contracts for up to 8 Artemis missions. 4 core stages are now in varying stages of completion, 2nd to be delivered in March. 16 engines are ready, booster segments for 3 launches are ready for stacking, ICPS for 3 launches, first EUS for certification.

SpaceX's Starship is to be fully reusable, and no one thinks they spent $25B to develop it. Also, arguably it began serious development in 2017, and 5 years later they have a prototype.

This again is a misunderstanding. The design goal of SLS is to maximize characteristic energy (C3) delivered to a given payload on orbit. Starship design goal is reusability. These are opposing trade constraints for any rocket. SLS gives up reusability for C3. Starship gives up C3 for reusability. Musk has not invented new physics, or knowledge that NASA doesn't have. That is another of the fallacies. Both are accountable to the rocket equation.

The consequence of this is that SLS needs no other supporting infrastructure. It can send payloads on direct trajectories within the solar system, in a single launch. That was the intent. In contrast, Starship cannot send a payload out of earth orbit, because it lacks C3.

To get around this limitation, Starship requires orbital refueling, an infrastructure that doesn't yet exist. With sufficient propellant addition in orbit, Starship can match the C3 of SLS. To do this requires both an orbital depot, and more than a dozen additional launches of propellant to the depot. So that is at least 14 launches to SLS single launch.

In return for that cost, both Starship and the Super Heavy booster can be reusable. But to be competitive, those launches will need to be below $100M each. SpaceX is not able to do that with Falcon Heavy. In time it may be possible with Starship. But that will also require a frequent launch cadence, and the heavy lift market to support it. That too, does not exist yet.

As stated, I hope that all these things can be achieved, that would be a great benefit to our space capabilities. But they will require significant investment. Given where the Starship prototype is now, I could easily see that investment reaching $20B to $25B, to build out & maintain the Starship & orbital refueling infrastructure, in a safe and reliable way.

Question: Would you rather have Starship with it's development costs and timeline, or SLS with it's development costs and timeline?

From the above, I don't see them being that different, when the actual realities are considered.

What I would truly rather have, is the real vehicle that is ready to go, that has both known costs and performance. But also to make the needed investments for the prototype vehicle, whose costs and performance are still unknown, to make that capability a reality as well.

The notion that we need decide, one or the other, is yet another of the fallacies put forward.

Thus the goal NASA is pursuing now, is supporting both programs, so as to develop both capabilities. That is the logical and rational thing to do, when the full picture is understood. Unfortunately, it's not understood by the people howling for the demise of NASA or SLS.

Would an expendable Starship / Booster combo be able to deliver the same C3 as SLS?

Avatar2go wrote:

kitplane01 wrote:

No one I've met knows the future ... but I think one can make a strong argument that for NASAs launch system "burn it to the ground and contract everything to ULA/SpaceX" would be exactly right. I'd wonder if you would get twice the speed at half the cost.

I believe this argument is largely based on misunderstanding of the industry. At the time SLS was conceived, there was no commercial entity that could have undertaken the project. As I mentioned, it's a fallacy that has taken root amongst Musk supporters, but Musk himself does not make this claim.

We didn't communicate right.

I'm not saying "In 2010 SpaceX could have done this stuff". I'm saying "In 2017 they should have burned it to the ground and started again".
My claim is the ~$12B that has been spent in the last 5 years, if given to SpaceX, could have bought something even better than Starship.

Avatar2go wrote:

kitplane01 wrote:

SLS (which is the thing making the news now) was supposed to cost $10B, incremental cost $0.5B per launch, and require 7 years. It's now at $25B, $2B per launch, and 12 years. I think SpaceX could do better, and I *hope* ULA could.

These are fair criticisms, apart from the fallacy regarding SpaceX/ULA capability. But if you tell the whole story, the program changed direction with each administration, except the current one. And was consistently funded at $2B - $3B per year for most of its development life. Of the $93B you quoted, the majority occurs in the last 3 years after launch operations have begun.

The issue that arises with flat funding, is that you extend and inflate labor and facility costs, in return for a predictable budget. If there are delays, which there always are in all space programs, those costs accumulate because you can't divest expertise or shut down buildings during the delay. Even if the delays are non-technical, like COVID & storm damage.

And note that SpaceX doesn't have these problems.

It's not clear if you're saying "It's not NASA's fault" or "Look how messed up the government is". I'm saying which one you pick doesn't matter because either way it sux.

Avatar2go wrote:

kitplane01 wrote:

SpaceX's Starship is to be fully reusable, and no one thinks they spent $25B to develop it. Also, arguably it began serious development in 2017, and 5 years later they have a prototype.

This again is a misunderstanding. The design goal of SLS is to maximize characteristic energy (C3) delivered to a given payload on orbit. Starship design goal is reusability. These are opposing trade constraints for any rocket. SLS gives up reusability for C3. Starship gives up C3 for reusability. Musk has not invented new physics, or knowledge that NASA doesn't have. That is another of the fallacies. Both are accountable to the rocket equation.

The consequence of this is that SLS needs no other supporting infrastructure. It can send payloads on direct trajectories within the solar system, in a single launch. That was the intent. In contrast, Starship cannot send a payload out of earth orbit, because it lacks C3.

To get around this limitation, Starship requires orbital refueling, an infrastructure that doesn't yet exist. With sufficient propellant addition in orbit, Starship can match the C3 of SLS. To do this requires both an orbital depot, and more than a dozen additional launches of propellant to the depot. So that is at least 14 launches to SLS single launch.

In return for that cost, both Starship and the Super Heavy booster can be reusable. But to be competitive, those launches will need to be below $100M each. SpaceX is not able to do that with Falcon Heavy. In time it may be possible with Starship. But that will also require a frequent launch cadence, and the heavy lift market to support it. That too, does not exist yet.

As stated, I hope that all these things can be achieved, that would be a great benefit to our space capabilities. But they will require significant investment. Given where the Starship prototype is now, I could easily see that investment reaching $20B to $25B, to build out & maintain the Starship & orbital refueling infrastructure, in a safe and reliable way.

Actually I already knew all this (though its nice to be reminded).

Lets suppose both work as intended (though I doubt SLS will ever be reliable or on it's newer, even more inflated budget).

Starship builds something we've never had before. It's both reusable, and large enough to get human capsule sized payloads (with refueling) out of earth orbit. Starship gets us closer to a future we want: cheaper access to deep space. SLS is reusing a bunch of existing tech to make a newer Saturn V.

I bet your vision of the 20 years from now future includes nothing like the SLS, and a lot like Starship.

kitplane01 wrote:

Avatar2go wrote:

kitplane01 wrote:

No one I've met knows the future ... but I think one can make a strong argument that for NASAs launch system "burn it to the ground and contract everything to ULA/SpaceX" would be exactly right. I'd wonder if you would get twice the speed at half the cost.

I believe this argument is largely based on misunderstanding of the industry. At the time SLS was conceived, there was no commercial entity that could have undertaken the project. As I mentioned, it's a fallacy that has taken root amongst Musk supporters, but Musk himself does not make this claim.

We didn't communicate right.

I'm not saying "In 2010 SpaceX could have done this stuff". I'm saying "In 2017 they should have burned it to the ground and started again".
My claim is the ~$12B that has been spent in the last 5 years, if given to SpaceX, could have bought something even better than Starship.

Avatar2go wrote:

kitplane01 wrote:

SLS (which is the thing making the news now) was supposed to cost $10B, incremental cost $0.5B per launch, and require 7 years. It's now at $25B, $2B per launch, and 12 years. I think SpaceX could do better, and I *hope* ULA could.

These are fair criticisms, apart from the fallacy regarding SpaceX/ULA capability. But if you tell the whole story, the program changed direction with each administration, except the current one. And was consistently funded at $2B - $3B per year for most of its development life. Of the $93B you quoted, the majority occurs in the last 3 years after launch operations have begun.

The issue that arises with flat funding, is that you extend and inflate labor and facility costs, in return for a predictable budget. If there are delays, which there always are in all space programs, those costs accumulate because you can't divest expertise or shut down buildings during the delay. Even if the delays are non-technical, like COVID & storm damage.

And note that SpaceX doesn't have these problems.

It's not clear if you're saying "It's not NASA's fault" or "Look how messed up the government is". I'm saying which one you pick doesn't matter because either way it sux.

I'm saying your suggestion is not feasible, because the capacity to do that still lies in the future. SpaceX has never suggested that they could or should have taken over Artemis. It's purely a fan fiction.

Your assertion that funding does not control the rate of progress at SpaceX is also not valid. Musk himself has said they have to pick and choose the aspects of Starship to push forward, because of limited resources. He has a lot of ideas for improvement, he basically never stops thinking in those terms. But the physical and fiscal reality is that you have to define limits and work toward them. SpaceX does this just like NASA, and just like every other organization.

kitplane01 wrote:

Avatar2go wrote:

kitplane01 wrote:

SpaceX's Starship is to be fully reusable, and no one thinks they spent $25B to develop it. Also, arguably it began serious development in 2017, and 5 years later they have a prototype.

This again is a misunderstanding. The design goal of SLS is to maximize characteristic energy (C3) delivered to a given payload on orbit. Starship design goal is reusability. These are opposing trade constraints for any rocket. SLS gives up reusability for C3. Starship gives up C3 for reusability. Musk has not invented new physics, or knowledge that NASA doesn't have. That is another of the fallacies. Both are accountable to the rocket equation.

The consequence of this is that SLS needs no other supporting infrastructure. It can send payloads on direct trajectories within the solar system, in a single launch. That was the intent. In contrast, Starship cannot send a payload out of earth orbit, because it lacks C3.

To get around this limitation, Starship requires orbital refueling, an infrastructure that doesn't yet exist. With sufficient propellant addition in orbit, Starship can match the C3 of SLS. To do this requires both an orbital depot, and more than a dozen additional launches of propellant to the depot. So that is at least 14 launches to SLS single launch.

In return for that cost, both Starship and the Super Heavy booster can be reusable. But to be competitive, those launches will need to be below $100M each. SpaceX is not able to do that with Falcon Heavy. In time it may be possible with Starship. But that will also require a frequent launch cadence, and the heavy lift market to support it. That too, does not exist yet.

As stated, I hope that all these things can be achieved, that would be a great benefit to our space capabilities. But they will require significant investment. Given where the Starship prototype is now, I could easily see that investment reaching $20B to $25B, to build out & maintain the Starship & orbital refueling infrastructure, in a safe and reliable way.

Actually I already knew all this (though its nice to be reminded).

Lets suppose both work as intended (though I doubt SLS will ever be reliable or on it's newer, even more inflated budget).

Starship builds something we've never had before. It's both reusable, and large enough to get human capsule sized payloads (with refueling) out of earth orbit. Starship gets us closer to a future we want: cheaper access to deep space. SLS is reusing a bunch of existing tech to make a newer Saturn V.

I bet your vision of the 20 years from now future includes nothing like the SLS, and a lot like Starship.

You are arguing over nothing here. I clearly said that I hope Starship works out, and that we need both options in the long run. They are both useful in the NASA toolbox, as are all the other launch platforms that are in development.

The reality as I said, is that Starship does not compete with SLS, they have different design goals and purposes. So the notion that we should scrap one to feed the other, is nonsensical. Neither NASA nor SpaceX believes in that path.

I bet your vision of the 20 years from now future includes nothing like the SLS, and a lot like Starship.

Exactly.

SLS is an expensive way of getting to the moon. It uses out of date technology to do not much of anything except put a capsule in moon orbit. It cannot even land and return a mission to the moon without a separate lander being supplied by SpaceX. Starship will be able to put in excess of 100 tons in to low earth orbit. In other words the hard work is done. This makes for a much more flexible system. Even a combination of two or three Falcon Heavy launches at 90 million each could accomplish the same as a single SLS launch costing 4 billion. Sure there would be a cost to develop some additional hardware and there would be the need to probably refuel spacecraft but you have the same situation already with SLS anyway.

No matter how you spin it ULA is fleecing the government. Who do you bet on? Before SpaceX ULA did maybe a dozen launches a year. Their Atlas 5 uses Russian engines, costs about three times the price of a Falcon 9 and puts less payload in to orbit. Vulcan is late and it is using engines that are still not ready. In the meantime SpaceX has continually upgraded Falcon9. Fielded Falcon Heavy and is on the cusp of launching a super heavy orbital class rocket. If NASA had spent a fraction of the billions spent on SLS helping SpaceX develop Starship we would be on Mars already.

Avatar2go wrote:

kitplane01 wrote:

Avatar2go wrote:

I believe this argument is largely based on misunderstanding of the industry. At the time SLS was conceived, there was no commercial entity that could have undertaken the project. As I mentioned, it's a fallacy that has taken root amongst Musk supporters, but Musk himself does not make this claim.

We didn't communicate right.

I'm not saying "In 2010 SpaceX could have done this stuff". I'm saying "In 2017 they should have burned it to the ground and started again".
My claim is the ~$12B that has been spent in the last 5 years, if given to SpaceX, could have bought something even better than Starship.

Avatar2go wrote:

These are fair criticisms, apart from the fallacy regarding SpaceX/ULA capability. But if you tell the whole story, the program changed direction with each administration, except the current one. And was consistently funded at $2B - $3B per year for most of its development life. Of the $93B you quoted, the majority occurs in the last 3 years after launch operations have begun.

The issue that arises with flat funding, is that you extend and inflate labor and facility costs, in return for a predictable budget. If there are delays, which there always are in all space programs, those costs accumulate because you can't divest expertise or shut down buildings during the delay. Even if the delays are non-technical, like COVID & storm damage.

And note that SpaceX doesn't have these problems.

It's not clear if you're saying "It's not NASA's fault" or "Look how messed up the government is". I'm saying which one you pick doesn't matter because either way it sux.

I'm saying your suggestion is not feasible, because the capacity to do that still lies in the future. SpaceX has never suggested that they could or should have taken over Artemis. It's purely a fan fiction.

Your assertion that funding does not control the rate of progress at SpaceX is also not valid. Musk himself has said they have to pick and choose the aspects of Starship to push forward, because of limited resources. He has a lot of ideas for improvement, he basically never stops thinking in those terms. But the physical and fiscal reality is that you have to define limits and work toward them. SpaceX does this just like NASA, and just like every other organization.

I'm saying that you misunderstand. I don't want SpaceX to make the SLS (though I'd be my house they would do a better job than NASA).
I'm saying I want SpaceX to make Starship, or Falcon Heavy ... and if you really want to go to the moon with fragile humans to use Starship. or Falcon Heavy. Don't the waste time and money on the over expensive, way late, fire-dump, repurposed old technology SLS.

SLS gets us to the moon, but is a dead end technologicaly. Both Falcon and Starship moves us toward a future of cheaper access to space, which makes everything including lunar missions better.

Avatar2go wrote:

kitplane01 wrote:

Avatar2go wrote:

This again is a misunderstanding. The design goal of SLS is to maximize characteristic energy (C3) delivered to a given payload on orbit. Starship design goal is reusability. These are opposing trade constraints for any rocket. SLS gives up reusability for C3. Starship gives up C3 for reusability. Musk has not invented new physics, or knowledge that NASA doesn't have. That is another of the fallacies. Both are accountable to the rocket equation.

The consequence of this is that SLS needs no other supporting infrastructure. It can send payloads on direct trajectories within the solar system, in a single launch. That was the intent. In contrast, Starship cannot send a payload out of earth orbit, because it lacks C3.

To get around this limitation, Starship requires orbital refueling, an infrastructure that doesn't yet exist. With sufficient propellant addition in orbit, Starship can match the C3 of SLS. To do this requires both an orbital depot, and more than a dozen additional launches of propellant to the depot. So that is at least 14 launches to SLS single launch.

In return for that cost, both Starship and the Super Heavy booster can be reusable. But to be competitive, those launches will need to be below $100M each. SpaceX is not able to do that with Falcon Heavy. In time it may be possible with Starship. But that will also require a frequent launch cadence, and the heavy lift market to support it. That too, does not exist yet.

As stated, I hope that all these things can be achieved, that would be a great benefit to our space capabilities. But they will require significant investment. Given where the Starship prototype is now, I could easily see that investment reaching $20B to $25B, to build out & maintain the Starship & orbital refueling infrastructure, in a safe and reliable way.

Actually I already knew all this (though its nice to be reminded).

Lets suppose both work as intended (though I doubt SLS will ever be reliable or on it's newer, even more inflated budget).

Starship builds something we've never had before. It's both reusable, and large enough to get human capsule sized payloads (with refueling) out of earth orbit. Starship gets us closer to a future we want: cheaper access to deep space. SLS is reusing a bunch of existing tech to make a newer Saturn V.

I bet your vision of the 20 years from now future includes nothing like the SLS, and a lot like Starship.

You are arguing over nothing here. I clearly said that I hope Starship works out, and that we need both options in the long run.

I'm argung we don't need or want SLS. We don't need both options in the long run. The long run better not include $2B/launch, expendable rockets. That's not the right future. The right future is reusable rockets, which SLS will never be.

Does your long run really include $2B per launch expendible rockets?

bobinthecar wrote:

I bet your vision of the 20 years from now future includes nothing like the SLS, and a lot like Starship.

No matter how you spin it ULA is fleecing the government.

Actually, I'd guess that profits for ULA are just not that high. Also, they are not the low cost provider