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This topic was created by Louis in 2015, and it has been sitting unanswered since then.
Today's launch of SLS is a good opportunity to bring this topic back into view, and perhaps to see how it holds up after 7 years.
https://www.msn.com/en-us/news/technolo … b5960ad93c
The New York Times
How the ‘Red Crew’ Saved NASA’s Moon Launch
Michael Roston - 1h agoValiant effort was on display throughout the Kennedy Space Center on Wednesday when NASA’s Artemis I rocket lifted off toward the moon. But something extra needs to be said about the red crew, three men who played a key role in getting the mission back on track.
NASA’s Space Launch System (SLS) rocket with the Orion spacecraft attached during final preparations on Tuesday.
© Kevin Dietsch/Getty ImagesThe red crew members were Trent Annis, Billy Cairns and Chad Garrett, and they did something dangerous and risky thing when they performed live repairs to fix a leak on a fueled rocket. For them, it was another day at the office, if the office was a thing that could reduce you to nothing more than a memory in an unfortunate instant.
“All I can say is we were very excited,” Mr. Annis said in an interview on NASA TV after the launch. “I was ready to get up there and go.”
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When a rocket is filled with propellants, human beings usually aim to be as far away as possible. A rocket in the best of circumstances is a controlled chemical reaction that lifts tons of material to space on a tower of fire. On its worst day, it is an explosive catastrophe that incinerates anything that gets too close.
So it was surprising on Tuesday during the launch countdown when Derrol Nail, the commentator on NASA’s live video feed, announced that real human beings were headed to the launchpad. Their goal was to fix parts on the Space Launch System, which was leaking hydrogen and threatening to ground the rocket — which by then had been packed full of huge quantities of explosive liquid hydrogen.
The red crew members and their minders drove up to the launchpad in a pair of white — not red — vehicles. Three characters in dark — again, not red — clothing ascended a part of the launch tower and got to work.
“We were very focused on what was happening up there,” Mr. Annis said in the post-launch interview. “It’s creaking, it’s making venting noises, it’s pretty scary.”
The precise work was unfamiliar to anyone who was not a rocket engineer. Mr. Nail described a need to “torque” something he described as “packing nuts.” On Twitter, NASA explained that bolts needed to be tightened because the valves they controlled might have been leaking.
While advanced technology is helpful, “there are also times when you’ve just got to put a wrench on a nut,” said Mike Bolger, the Exploration Ground Systems program manager at Kennedy Space Center, during a post-launch news conference on Wednesday.
Engineers in launch control then tested the valves, and whatever the red crew actually did worked. The leak had stopped. The loading of hydrogen into the rocket resumed.
While the red crew’s derring-do on Tuesday night was something, their work was not without precedent. A NASA spokeswoman highlighted the role such a group played in responding to a similar leak more than 50 years ago.
“We have sent a team of three technicians and a safety man to the pad and these technicians are now tightening bolts around the valve,” said a launch control commentator according to a NASA transcript from 1969. “Once the technicians depart, we will send hydrogen again through the system to assure that the leak has been corrected.”
The mission was Apollo 11, and the repair contributed to Neil Armstrong, Buzz Aldrin and Michael Collins making it to the moon.
About five hours after their brief visit to the launchpad, the Artemis I mission rocket was on its way to the moon, and the Red Team was on the ground, discussing its deeds with NASA’s on-air team. They highlighted that Mr. Cairns had been working on red crews for 37 years but his first time going to the launchpad in such a dangerous circumstance. Mr. Annis said during the interview that he had yet to fully appreciate his contribution to the mission.
“I still can’t believe it,” he said. “It’s surreal to me, just insane.”
Kayla Barron, an astronaut who has served aboard the International Space Station and provided on-air commentary for NASA for Wednesday’s launch, said that the three men’s experience shows how space exploration is a “team sport.”
“I think you guys perfectly demonstrated that today,” she said. “None of us could have accomplished this on our own.”
Kenneth Chang contributed reporting.
(th)
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The hydrogen leaks that have plagued this SLS core stage have all been in the core stage, not the on-pad infrastructure. For something as simple as loose gland packing nuts to have gone wrong, says a lot about the quality of the job Boeing did building this thing.
On the other hand, it did finally fly. That is a good thing, even though it is a decade late (and billions over budget) in happening.
If the next one shows similar leaks, and I was a responsible NASA manager, I would not risk the lives of a crew flying on it.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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For all regarding SLS flight ...
We have a ** lot ** of topics with SLS in the title, and anyone can create a new topic ...
I'm hoping our members will allow this slightly sarcastic topic by Louis to carry the load as SLS proceeds on it's mission.
It may actually work, but every part of the journey is a test so the unexpected is to be expected.
***
For GW Johnson .... I've tried to call attention to an interesting suggestion from long term member Grypd.
If you have time, please think about the implications of sourcing Oxygen from the Moon, while sourcing methane from Earth.
Are there any advantages to that concept. It may not be new, but this is the first time ** I've ** seen it.
(th)
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I watched the SLS / Artemis-I mission launch.
I'm glad they finally launched the rocket, but they're multiple years and billions of dollars over budget for something that was a good but not great idea in the absence of a fully reusable Starship. SLS was supposed to be cheaper than a Space Shuttle / STS launch, using proven STS program hardware. Each SLS mission will now cost considerably more than a STS mission, for a marginal increase in total lift capability when one considers both the Space Shuttle orbiter and its payload. That was not the intent behind using the remaining STS hardware, and then new-build SLS hardware. There is also no potential cost reduction associated from conducting SLS launches in conjunction with STS launches drawing from the same or a very similar hardware base. SLS or something like it made a lot more sense while the STS program still existed. Now that STS is gone, SLS is another giant money pit that confers no advantages to NASA or for human space flight in general.
By virtue of existing, meaning being more than a paper launch vehicle concept, SLS scores some points in my book. However, SLS is so cost-prohibitive to use and component fabrication takes so long as to make NASA's current lunar and later Mars exploration plans unworkable. They'll use the program to goof off with building a space station in lunar orbit, maybe land a few times for flags and footprints, and then they have no more budget left for all the rest of their stated program goals.
A suitable launch vehicle is a hard requirement for exploration missions, but SLS is not suitable for what NASA wants to do, hence it contracted with SpaceX to do actual landings, because NASA has no funding left to do those landings without entirely outsourcing that capability to SpaceX.
If Starship successfully demonstrates orbital refueling, then SLS ceases to have a reason to exist. It's a technological dead-end, it was from the very beginning, and NASA knew that. The agency should've pushed back on politicians who don't understand anything about mechanical engineering or all the other aspects of space flight that dictate workable solutions.
A reprisal of Saturn V is what SLS has become, except that F-1A engines with RS-25 upper stage engines would've been inordinately cheaper, more practical, and faster to achieve with their budget. The use of solid strap-on boosters imposes lots of cost and risk and delays. If the entire booster stage was a single giant solid rocket, then I could see the wisdom of using all that fantastic thrust output in conjunction with a RS-25 powered upper stage, but NASA's Ares-I vehicle (proof-of-concept of the giant solid attached to a LOX/LH2-fueled J-2X-powered upper stage) was cancelled due to its own show-stopper technical problems.
So, all-liquid was always the way to go for a reusable or low-cost expendable booster. LOX/RP-1 and F-1A were the low-cost alternative to STS technology, and a 10m diameter first stage, a reprisal of Saturn V using modern hardware, was the way to go to re-create Saturn V capabilities using modern engines. Heck, they re-developed and flight-qualified J-2X and were in the process of recreating F-1A, which was the correct way to re-create a Saturn-V type vehicle.
So... Kudos to NASA and their contractors for recreating a much more expensive Saturn-V with greatly reduced performance. If they want a pat on the back, they're not going to get it from me or anyone else who has a basic understanding of what they did. Every solution they've concocted has been less affordable, more complex, and less practical than what came before it. They get credit for actually launching the rocket before cancellation, but no real improvement in capabilities is on offer from what they've come up with and far less money for actual missions is available as a result.
Similarly, they milled around with space suit development for decades now, knowing full well that their new solutions don't work if real mobility is required for extended EVAs. Nobody on the contractor side is willing to tell them to quit reinventing the wheel. Speaking of literally reinventing the wheel, NASA also ran an article on their website some years back about how they literally reinvented the wheel for lunar rover tires. Those of us who understand how silly this has become are unhappy because we realize how much money, time, and engineering talent has been squandered on trivial pursuits. I award NASA no points for taking our tax money and reinventing wheels. It's busy work that's meant to confuse curious but ignorant onlookers who can't distinguish between a flurry of activity and real accomplishment.
Real accomplishment would be using the existing rockets to at least orbit the moon with real humans, or sending scouts in small landing craft to locate and confirm the presence of subsurface ice at the lunar poles. I aware a lot more points for doing that, because it shows measurable progress towards the agency's own stated lunar exploration program objectives.
I want water for rockets, sourced from the moon. - NASA
So, use the hardware you have (Dragon and Falcon Heavy and a small lander of the type experimented with but never developed into working hardware) to send someone to the surface, collect a bag of material, see if you get a lot of water, and then you're at least at the point where you can consider how to extract it and use it. At that point, you build and land a proof-of-concept machine. They could've done that without SLS or Starship or a lunar space station or new space suits or any other nonsense. The mega rocket comes after you prove out what you'll do with it that requires it. Gemini was the "proof of concept" phase of the Apollo program, for example. Similarly, SpaceX could've proven their orbital refueling concept using Falcon Heavy launches.
Why was that never done?
Grand ideas over pragmatic ones that demonstrate clearly measurable progress towards stated goals. People know if you're making progress or messing up rather quickly, before billions of dollars are spent on dead-end programs. We can't have any of that, now can we?
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NASA is a government agency beholden to congress. What congress cared about was keeping the very considerable industries and jobs associated with shuttle, running after its termination. That is why SLS exists. It wasn't about providing a practical vehicle for any programme in particular. It was a political solution looking for a problem.
If Starship flys and is succesful at a tiny fraction of the cost of SLS, you can expect SLS to get dumped. Starship is not demonstrated yet, so there isn't much pressure to do this at present. As things stand, Starship is an undemonstrated concept. It only becomes an alternative once it is demonstrated. When that happens, it could catalyse a transformation of space industry. Whilst congress does want to protect jobs, they do care about cost. And if Musk can produce capable rockets at a fraction of the cost of government programmes, maybe he can do the same for space suits, or moon buggies? This sort of reckoning is far more likely with a Republican controlled congress.
Congress have been willing to tolerate huge inefficiency in the space programme because it was never a commercial operation. The payback was jobs in key constituencies. It was a high tech way of giving peopke something to do, whilst maintaining American prestige. When it becomes clear that America has a commercial player capable of hugely enhancing space capabilities, there will be behind the scenes discussions about how to use that resource, whilst repurposing as much existing industry (and jobs) as possible. At present, there is no appetite for this, because congress aren't actually interested in the end results. But if Starship presents them with the option for doing things that are well beyond present capabilities, then end results become more interesting.
Last edited by Calliban (2022-11-17 05:49:47)
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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Calliban,
I wanted to put a SLS core stage on top of a Starship booster stage for a very capable, albeit expendable, super heavy lift vehicle.
There are other rocket boosters (Atlas, now Vulcan) that make use of large solids, so the military side of solid rocket technology is not lost.
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