[HN Gopher] Artemis I Launch Attempt Scrubbed
       ___________________________________________________________________
        
       Artemis I Launch Attempt Scrubbed
        
       Author : Trouble_007
       Score  : 97 points
       Date   : 2022-09-03 15:27 UTC (7 hours ago)
        
 (HTM) web link (blogs.nasa.gov)
 (TXT) w3m dump (blogs.nasa.gov)
        
       | [deleted]
        
       | allenrb wrote:
       | Consequences of choosing the wrong first stage fuel (hydrogen)
       | are many.
       | 
       | Those tiny molecules want nothing more from life than to sneak
       | through the smallest of openings. Well, possibly second to mating
       | violently with oxygen.
        
         | WalterBright wrote:
         | Doolittle: Bomb, what is your purpose?
         | 
         | Bomb: To explode, of course.
        
           | 2OEH8eoCRo0 wrote:
           | Dark Star. Good movie.
        
             | WalterBright wrote:
             | A forgotten classic.
        
             | IshKebab wrote:
             | IMDB disagrees! 6.2.
        
               | pram wrote:
               | It's a gestalt imo, kinda like Lynch's Dune. Flawed film
               | with lots of bad parts and bizarre decisions, but also
               | unique and memorable enough to elevate it above 'just
               | bad'
        
               | melling wrote:
               | 6.2 isn't good but this is a John Carpenter movie,
               | written and directed.
               | 
               | In fact, it was his student film.
               | 
               | Looks like he was going for a 2001 A Space Odyssey feel.
        
               | pengaru wrote:
               | > Looks like he was going for a 2001 A Space Odyssey
               | feel.
               | 
               | I thought he was communicating just how _boring_ and time
               | consuming space exploration will be, being such vast
               | emptiness.
        
         | TT-392 wrote:
         | It is what their engines use, and they weren't gonna use
         | different engines
        
         | jmyeet wrote:
         | "Wrong" by what standard? Hydrogen has the highest specific
         | impulse but I'd much harder to work with. We have no better
         | propellant.
         | 
         | A lot of other launch vehicles use RP-1, which is basically
         | just kerosene. Lower specific impulse so lower payload capacity
         | but it doesn't need to be cryogenically stored and cooled with
         | everything that entails.
         | 
         | That's a fine choice for single use rockets but when you get
         | into reusable rockets you now have a new problem: RP-1 burns
         | and leaves a lot of carbon behind. This is costly and slow to
         | clean.
         | 
         | For this reason SpaceX's next rocket uses methane. Like
         | hydrogen or must be cooled but not as much. Still it's more
         | complex engineering.
         | 
         | Artemis to me seems too expensive but it will be the most
         | powerful launch vehicle ever created with the highest payload
         | capacity.
         | 
         | So how is it wrong?
        
           | wolfram74 wrote:
           | as you said, RP-1 is probably a better choice for throwaway
           | rockets, which SLS is.
        
           | AstralStorm wrote:
           | Unfortunately methane being a GHG brings additional important
           | problems. Launching a lot of methane rockets would be really
           | expensive to the environment.
           | 
           | (We need to finally replace SRBs with something cleaner too.)
        
             | DanBC wrote:
             | > Launching a lot of methane rockets would be really
             | expensive to the environment.
             | 
             | What does it turn into when burnt? Would there be much
             | unburnt methane leaking into the environment from these
             | rockets and the infrastructure to support these rockets?
        
               | fuzzfactor wrote:
               | Methane is the simplest hydrocarbon. CH4.
               | 
               | One molecule of methane combines with two molecules of
               | oxygen to form one molecule of carbon dioxide along with
               | two molecules of water. Releasing good amounts of energy
               | when this reaction (oxidation of hydrocarbons by simply
               | burning them) is taking place.
               | 
               | CH4 + 2 O2 = CO2 + 2 H2O
               | 
               | Hydrogen is the simplest flammable gas. H2, in molecular
               | form.
               | 
               | 2 H2 + O2 = 2 H2O
               | 
               | Two molecules of hydrogen combine with one molecule of
               | oxygen to form two molecules of water with no other
               | byproducts. Lots of energy comes out too when hydrogen
               | burns but it is a completely clean gas unlike any other.
               | If hydrogen can be manufactured using only green energy,
               | it is completely benign to the environment when burned.
               | Also harmless when released unburnt as long as it doesn't
               | cause any fires or asphyxiation or something.
               | 
               | OTOH when the methane burns it turns into an equal number
               | of carbon molecules in the atmosphere in the form of CO2.
               | Fortunately the CO2 has a lesser greenhouse effect than
               | if the unburnt methane were directly released (or leaked)
               | into the environment.
               | 
               | As it is now, any methane likely to be used as rocket
               | fuel would alternatively just be turned into atmospheric
               | CO2 by some other terrestrial user of natural gas anyway.
               | Without launching any spacecraft.
               | 
               | Methane fuel still puts CO2 into the atmosphere at the
               | push of a button, which would require a herculean effort
               | to remove later, and that removal would not be
               | justifiable until the situation is much more dire, as we
               | have seen.
               | 
               | Still, methane really can be considered the cleanest
               | burning hydrocarbon, but nowhere near the zero-CO2
               | exhaust from a hydrogen flame.
               | 
               | Both of these gaseous fuels are so light they do not like
               | to be physically liquified at all, not even when highly
               | pressurized, and that would require very heavy-walled
               | storage cylinders in that case. But they still need to be
               | stored as a liquid in order to carry orders of magnitude
               | more fuel than the same size tank would hold in gaseous
               | form. So they use extreme low-temperature cryogenics to
               | liquefy these fuels and the storage & handling is
               | accomplished at temperatures so far below zero that the
               | product remains liquid without needing to be kept under
               | very much pressure. Instead, it's handled _very cold at
               | all times_ with lots of insulation  & refrigeration. If
               | it warms up too much the pressure rise _is certainly
               | expected_ to exceed the design maxiumum of the storage
               | tank, so all safety relief devices must be highly
               | reliable under these conditions.
               | 
               | There's this thing about cryogenics.
               | 
               | Everything can't be expected to work right the first
               | time, and success may not be had until all possible
               | failures have already been witnessed to occur, and
               | further design experience has been gained developing the
               | workarounds.
        
           | allenrb wrote:
           | It's wrong because hydrogen in the first stage optimized for
           | things you don't care about, namely propellant mass. In
           | exchange, you get heavier tanks, physically larger engines,
           | and (obviously) more complex operations.
           | 
           | Yes, it has the highest practical specific impulse. No, that
           | is not the most important metric for a lower stage. Take a
           | look at how many new launchers are using hydrogen in their
           | lower stages. Hint: it's a big, round sort of a number.
        
         | mabbo wrote:
         | Like all engineering decisions, hydrogen is a choice with
         | tradeoffs.
         | 
         | It's specific impulse ('fuel efficiency') is unbeatable. That
         | buys you a lot more cargo capacity for the same sized rocket.
         | And since this program is putting large items into lunar orbit,
         | you need that badly.
         | 
         | But as you said, it's... complex to work with.
         | 
         | Hey it worked for the space shuttle.
        
           | xcskier56 wrote:
           | Another trade off:
           | 
           | Liquid hydrogen is very low density, and requires extremely
           | low temperatures.
           | 
           | This means that you need a much bigger tank for a given
           | weight of fuel, and that tank needs to be insulated bc liquid
           | hydrogen must be kept below 33 kelvin.
           | 
           | Both of these downsides can come close to negating the upside
           | of increased ISP.
           | 
           | But the upside for SLS is that they already had engines that
           | can run on hydrogen. Like you said, trade offs all around
        
           | adastra22 wrote:
           | > That buys you a lot more cargo capacity for the same sized
           | rocket.
           | 
           | I think you mean the same mass rocket, because hydrogen is
           | not dense, which factors into the tradeoffs (more structural
           | mass to contain it).
        
             | mabbo wrote:
             | An excellent point.
             | 
             | Fortunately bigger tanks get better and better the bigger
             | they are. The mass of the tanks is _mostly_ a function of
             | it 's surface area, growing with n^2, while the fuel stored
             | grows by n^3.
             | 
             | And the SLS tank is pretty darned big indeed, with a very
             | large diameter.
        
               | wumpus wrote:
               | Big tanks are a big part of why SLS is financially
               | inefficient.
        
         | numpad0 wrote:
         | There are just as many hydrolox(hydrogen + liquid oxygen) as
         | kerolox(RP-1 kerosene + LOX). Atlas, Delta, H-II, Ariane 5,
         | Long March 5, to name a few, all use hydrolox.
         | 
         | I believe a part of reasons why launch attempts are called
         | "attempts" is because of extreme scrub and failure rate of
         | launch vehicle launches, and I think the fact that scrubs are
         | now considered abnormal can be attributable to SpaceX and Elon
         | Musk. I was old enough to remember watching last few of Space
         | Shuttle launch attempts, and from my experience watching launch
         | streams, scrubs and recycling due to hydrogen leaks, erratic
         | sensor readings, upper atmosphere weather, and private boats
         | and planes violating keepout areas were entirely normal events,
         | with a global sole exception of the Soyuz launch vehicle flying
         | from Baikonur Cosmodrome, which delayed or failed up to once in
         | a decade or so.
         | 
         | Apparently it pisses off people in power, sometimes might have
         | caused off-season human resource reallocations, but rocketeers
         | basically never cared. That was until Falcon 9 started
         | launching on first tries of each attempts.
        
           | allenrb wrote:
           | I'm a big fan of SpaceX and (when he can keep his mouth shut
           | about US politics and a dozen other things) Elon Musk, but
           | they're hardly the first ones to launch without regular
           | scrubs. ULA does it all the time. So does arianespace. The
           | Russians are pretty good at it, though aerospace is yet
           | another sector of their economy being destroyed by Putin),
           | and the Chinese seem to get off the ground with some
           | regularity.
           | 
           | It's about mature vs immature vehicles, mostly. Much as I
           | loathe the entire SLS program and design of the rocket, it is
           | not because they're having some trouble with scrubs. That's
           | going to happen with a unique, complex, and new system.
        
           | jpgvm wrote:
           | I think the lack of scrubs of SpaceX launches mostly comes
           | from Falcon 9 being an absurdly powerful rocket with great
           | margin of safety for the payload/missions it takes. Thus it
           | can often launch in sub-optimal conditions, still complete
           | it's primary objective -and- recover the booster.
        
           | ericbarrett wrote:
           | True, but Delta IV is the only one of those rockets using
           | hydrolox for the first stage. I have to imagine storing and
           | moving that much hydrogen is a lot more complex than launch
           | vehicles that only use it in an upper stage.
        
             | numpad0 wrote:
             | I don't quite get the argument. If SLS and rest of those
             | rockets belong to a same category, and reliability in the
             | same level as well, what's the point of pointing that
             | out...besides I believe Delta IV Heavy is towards the side
             | of more reliable and regular launching rockets
        
         | theteapot wrote:
         | Worked pretty well for 135 shuttle missions.
        
           | wumpus wrote:
           | Let's see: killed a ton of people, was extremely expensive,
           | ...
        
             | koheripbal wrote:
             | A ton? Relative to what space program? Or do you mean a
             | physical measurement of the weight of people?
        
         | eternalban wrote:
         | How about magnetic containment? Does ionized hydrogen combust
         | well or not?
        
       | JumpCrisscross wrote:
       | We've been quoted $4bn per launch. If this pattern of delays
       | turns out to be fundamental (a big, if plausible, if), what would
       | the launch costs actually be?
        
         | thetinguy wrote:
         | Artemis is a federal jobs program.
        
           | tonetheman wrote:
           | Military budget for the year was 777B...
           | 
           | Give what you said all of the military is a jobs program
           | also.
        
             | DanHulton wrote:
             | You think you're being flip, but you're closer to right
             | than you probably expect.
        
             | [deleted]
        
             | arrosenberg wrote:
             | The military is a jobs program, thats not a secret.
        
             | JumpCrisscross wrote:
             | Size of budget doesn't determine jobs or not. Artemis
             | exists because Congress didn't like Constellation's
             | cancellation. Its Block II configuration underperforms
             | Starship at significantly higher cost, both to develop and
             | to operate, all without anywhere close to the technological
             | progress of even Falcon Heavy. SLS exists first to provide
             | jobs. The military-industrial complex has an obvious first
             | and foremost purpose, and it's pretty good at it.
        
           | RichardCNormos wrote:
           | The mission of Artemis is to land a woman and a person of
           | color on the moon. It is a federally funded affirmative
           | action program.
        
         | Robotbeat wrote:
         | This is normal for any new launch vehicle.
         | 
         | ...which is why it's often a good idea to not use a new launch
         | vehicle on the critical path for your crewed spaceflight
         | program. (Could have used LEO rendezvous of various types to go
         | to the Moon.)
         | 
         | https://spacecraft.ssl.umd.edu/akins_laws.html
         | 
         |  _> 39. The three keys to keeping a new human space program
         | affordable and on schedule: 1) No new launch vehicles. 2) No
         | new launch vehicles. 3) Whatever you do, don 't develop any new
         | launch vehicles._
        
           | somenameforme wrote:
           | The initial SpaceX Falcon rocket was entirely privately
           | funded, at a total cost of of ~$100 million. The first 3
           | launches were failures. The 4th launch was a success, and the
           | rest is history. And that vessel would ultimately go on
           | (through various again largely privately funded innovations)
           | to revolutionize spaceflight.
           | 
           | The same is now true of the Starship, which is again being
           | entirely privately funded. The cost is certainly going to be
           | much more than $100 million, but also nowhere near the absurd
           | extremes of cost that Boeing imposes on the taxpayer. At this
           | point "we" have spent tens of billions of dollars on this
           | catastrophe. And the icing on the cake is that _if_ this
           | monstrosity is ever deemed flight worthy, it will likely
           | already be obsolete.
           | 
           | It's quite difficult to understand why giving a company
           | billions of dollars a year, _unless_ they succeed, does not
           | seem to be leading to great outcomes. Maybe we should just
           | give them more money. That 'll fix everything.
        
             | KennyBlanken wrote:
             | > The initial SpaceX Falcon rocket was entirely privately
             | funded, at a total cost of of ~$100 million.
             | 
             | And just to put things in perspective: SLS (not Orion,
             | _just_ SLS) is projected to cost a total of $30 Billion
             | 
             | The shuttle cost $1.5BN/launch and SLS, forty years later?
             | Over $2BN/launch.
             | 
             | Absolute insanity.
        
               | gsibble wrote:
               | I was downvoted a few weeks ago on a "Rah, rah, rah!
               | Artemis!" post here on HN for pointing out the same a few
               | weeks ago.
               | 
               | People on here sure are fickle.
        
       | perihelions wrote:
       | Likely no next attempt until October, per Eric Berger ( _Ars
       | Technica_ ):
       | 
       | - _" Hearing a rollback to the VAB of the SLS rocket is likely,
       | but I don't have confirmation. If that happens, it is very likely
       | that Artemis I does not launch before October 17, at the
       | earliest."_
       | 
       | - _" I'm told that Space Launch System program officials will
       | recommend a rollback to the VAB to investigate the hydrogen leak.
       | The Artemis I mission management team will consider this
       | recommendation at their afternoon meeting, and publicly announce
       | a decision at 4pm ET."_
       | 
       | https://twitter.com/SciGuySpace/status/1566088891395883009
       | 
       | https://twitter.com/SciGuySpace/status/1566104350635835393
        
         | madaxe_again wrote:
         | I have my doubts that it will _ever_ launch - the way things
         | are proceeding, they'll miss October, push to '23, and will
         | then end up with parts and systems ageing out due to wear and
         | duty cycles - the rollback to the VAB alone incurs significant
         | wear.
         | 
         | Meanwhile, starship will see its first orbital flight (likely
         | not before a few RUDs) while SLS just grows mould.
         | 
         | That said, the whole purpose of SLS was to provide jobs and to
         | retain technical expertise in the US, which it has achieved -
         | actually _launching_ the thing is almost besides the point.
        
           | hfgbvhevrt wrote:
           | When is that first starship orbital launch again?
        
             | rocket_surgeron wrote:
             | Starship doesn't even exist yet.
             | 
             | Note: neither Booster 7, nor Booster 8, or Ship 20 and 24
             | for that matter, are even close to being anything that
             | could be considered "Starship" by even the most generous
             | observer.
             | 
             | Even if B7/S24 do launch in a test flight they are so far
             | removed from anything that could potentially be in the far
             | future an operational and usable spacecraft that they
             | resemble "starship" the same way a wooden mockup of an
             | airplane resembles an actual airplane.
             | 
             | An object being the same general shape and dimensions of
             | something doesn't make that object the "something".
             | 
             | At least SLS exists and has problems that can be, perhaps,
             | probably at tremendous expense, fixed.
        
               | joe-collins wrote:
               | In 20 years, I've seen SpaceX start from scratch and
               | develop and launch the Falcon 1, Falcon 9, and Falcon
               | Heavy, and nail propulsive landings on Earth.
               | 
               | Since it's members joined forces to form ULA 15 years
               | ago, I've watched them launch the same machines they've
               | been using since 2002.
               | 
               | I have a lot more faith that SpaceX will launch something
               | new than that ULA will get anything done.
        
             | imtringued wrote:
             | Musk said he was going to Mars by 2018.
        
               | Teever wrote:
               | SpaceX could absolutely launch a mars mission with their
               | existing rocket platforms and launch infrastructure.
               | 
               | It would be tedious launching little pieces of a larger
               | ship and assembling them in orbit but it could absolutely
               | be done.
               | 
               | Instead of doing that they're choosing to build better,
               | bigger rockets, and more infrastructure to make the
               | eventual launches to mars more cost-effective and
               | substantial.
        
               | dwighttk wrote:
               | >Musk said he was going to Mars by 2018.
               | 
               | >SpaceX could absolutely launch a mars mission with their
               | existing rocket platforms and launch infrastructure.
               | 
               | If they launched today they'd be 4 years late
        
               | dsl wrote:
               | > SpaceX could absolutely launch a mars mission with
               | their existing rocket platforms and launch
               | infrastructure.
               | 
               | Which highlights the major difference between public and
               | private sector exploration. SpaceX killing everyone on
               | their first attempt is a tragedy and they quickly move
               | on, NASA doing it is a 10 year halt to any further work
               | until a full public investigation takes place.
        
           | gw99 wrote:
        
           | Angostura wrote:
           | It's a big, complex project and it's failed two tests. I'm
           | happy to take the bet that it _will_ launch successfully
        
             | KennyBlanken wrote:
             | It's a big complex project that legislators decreed should
             | re-use ancient engines and structural components from the
             | shuttle - a project that was the world's first space-faring
             | barrel of pork, infamous for its operating expenditures.
             | 
             | One of the arguments for doing so was that the engines were
             | "proven."
             | 
             |  _checks news story_
             | 
             | Oh hey, it's the engines that are causing these delays.
             | 
             | NASA has been so over-budget on the project, they had to
             | commit accounting fraud to try and cover it up.
        
               | kylegordon wrote:
               | Outright wrong.
               | 
               | "Multiple troubleshooting efforts to address the area of
               | the leak by reseating a seal in the quick disconnect
               | where liquid hydrogen is fed into the rocket did not fix
               | the issue"
        
               | mlyle wrote:
               | > Oh hey, it's the engines that are causing these delays.
               | 
               | ??? Last scrub was because of a problem with providing
               | bleed cooling to cold soak everything.
               | 
               | This scrub appears to be a problem with a quick
               | disconnect used in fueling operations or the piping just
               | inside it.
               | 
               | Neither are the "engines".
               | 
               | I'm skeptical of Artemis, but _come on_.
        
           | yarpnird wrote:
           | Think about all the work done by people that you are
           | discounting...
        
             | KennyBlanken wrote:
             | The work is shit, despite being done with forty year old,
             | thoroughly understood and matured technology?
             | 
             | https://arstechnica.com/science/2019/06/new-report-finds-
             | nas...
             | 
             | Cost overruns would have put NASA 33% over budget a few
             | years ago, but they committed accounting fraud to cover it
             | up.
             | 
             | The SLS is nothing more than a welfare check to Georgia and
             | Florida.
        
             | colordrops wrote:
             | A lot of work is put into making porn, facebook games,
             | prayer, cigarette manufacturing, the gambling industry etc.
             | I'm not saying these are all useless things, but most
             | people wouldn't bat an eye at someone "discounting" their
             | work. If the work going into SLS doesn't achieve anything,
             | then they discounted the work themselves, no need for a 3rd
             | party.
        
             | adastra22 wrote:
             | Since the rocket gets thrown in the ocean at the end of
             | this, this is literally the sunk cost fallacy at play.
        
               | gonesilent wrote:
               | NASA TV loves to show a great infographic of how many
               | parts have flown to space before and have been
               | reusable... can't help but yell in my mind.. and that's
               | the last time they'll be reusable.
        
               | adastra22 wrote:
               | Those engines belong in a museum.
        
               | jeffrallen wrote:
               | Maybe we should just park the turkey in the VAB and turn
               | the VAB into a museum.
        
               | awillen wrote:
               | It's not entirely sunk cost - there's reputational
               | effects for a lot of people involved. Politicians who
               | supported it look much worse if all this work (and money)
               | has gone into it, only to have it not launch. How bad
               | they will look is proportional to how much money was
               | spent/work was done, so the work put in does matter to
               | the outcome, at least for them.
               | 
               | That probably shouldn't be the case, but when it comes to
               | politics, perception is very much reality in that
               | people's perceptions translate directly to votes.
        
             | Teever wrote:
             | What is the point that you're trying to make here?
             | 
             | I'm sure we've all experienced situations where we realize
             | that the work we're being paid to do is futile and will
             | never reach achieve it's intended purpose. It's really
             | demoralizing but the thing to remember in that situation is
             | that you're still getting paid.
             | 
             | Would you rather be an aeronautical engineer who gets paid
             | and doesn't launch of a rocket, or an aeronautical engineer
             | who doesn't get paid and doesn't launch a rocket?
        
               | xwdv wrote:
               | I'd rather just be the aeronautical engineer who gets
               | paid to do nothing except stay in the U.S.
        
               | theteapot wrote:
               | > ... the thing to remember in that situation is that
               | you're still getting paid.
               | 
               | That's the spirit.
        
               | jeffrallen wrote:
               | I would rather NOT be the engineer who pays taxes so that
               | another engineer makes something that will never fly.
        
       | mholt wrote:
       | It's like the programmer who just runs their code again without
       | actually testing it in the hopes that something changed
        
         | bastawhiz wrote:
         | It's not, actually. They're not running anything. In fact,
         | they're doing the literal opposite of what your comment
         | suggests.
        
           | adastra22 wrote:
           | It's an accurate description of todays launch attempt. They
           | decided to repeat assuming the sensor problem that scrubbed
           | the last launch was a sensor issue only. It was not.
        
       | endymi0n wrote:
       | Does anyone get the point with Artemis? Because I really don't.
       | 
       | To my untrained eye the current outlook on the program looks like
       | that rocket is right now only supposed to make two roundtrips
       | along the moon -- and then in that third ,,Starship HLS" mission
       | Artemis' only job is to take up the astronauts to orbit: while
       | Starship (notably designed to be human rated) will be doing all
       | the heavy lifting of the mission.
       | 
       | In this context it all looks like a total sham, it would
       | literally be cheaper and easier to send them up in another
       | reusable Starship.
       | 
       | What other purpose does Artemis have except building the most
       | expensive trip to orbit existing so NASA can say ,,hey, we did
       | something about this moon mission too!"?
        
         | ceejayoz wrote:
         | > Does anyone get the point with Artemis?
         | 
         | Making Senators happy.
        
           | imglorp wrote:
           | Right, the Senate Launch System maximizes transfer of cash
           | from taxpayers to defense contractors.
           | 
           | There is absolutely no need to fly any hardware in the
           | process.
        
         | tiborsaas wrote:
         | They have the goal to build a moon base and establish human
         | presence there. This could lead to better research and we could
         | see the start of the industrialization of the moon. This looks
         | like something governments like to do and do it in government
         | style :)
         | 
         | Their site is a good start:
         | https://www.nasa.gov/specials/artemis/
         | 
         | And I've just skimmed this, but looks like a decent comparison
         | of SLS vs Starship:
         | 
         | https://everydayastronaut.com/sls-vs-starship/
        
         | theteapot wrote:
         | > Does anyone get the point with Artemis? Because I really
         | don't.
         | 
         | They want to go to the moon.
        
           | endymi0n wrote:
           | That's exactly what I mean. In their newest plan, they don't.
           | Someone else does.
        
             | theteapot wrote:
             | Who? They're all on the same team, team USA! Or are you
             | implying the glacial pace will inevitably mean China gets
             | there first?
        
               | endymi0n wrote:
               | So even if it was this easy and logical, the only logical
               | consequence would be scrapping SLS right now.
               | 
               | Artemis 3 isn't just depending on one, but two super
               | heavy launchers that haven't even left the ground yet.
               | 
               | And if you put Starship in the critical path, why would
               | you spend billions to introduce _another_ bottleneck
               | that's literally just duplicating Starship's ground to
               | orbit capability?
               | 
               | If NASA agenda really only was getting the USA to the
               | moon, the only rational choice would be doubling down on
               | Starship all the way.
        
           | huhtenberg wrote:
           | They want to keep lots of people employed.
        
         | jackmott wrote:
        
         | engineer_22 wrote:
         | When they started the project (2011) Starship wasn't even a
         | twinkle in Elon's eye (BFR around 2016). Starship started
         | looking like a real product in 2020. In hindsight, you're
         | right, SLS looks silly, but not many people were betting on
         | SpaceX developing a super heavy launch system in 6 years like
         | they've (apparently) done. They've invested a lot of money in
         | SLS and there's probably still lessons to learn there. If
         | Starship is successful SLS will probably not be deployed very
         | frequently.
        
       | minxomat wrote:
       | What's the record amount of scrubs?
       | 
       | I guess we have to ask TLC...
        
         | Rebelgecko wrote:
         | The record for the shuttle was 6
        
           | somenameforme wrote:
           | Make sure you're comparing apples to apples. Launches are
           | usually scrubbed because of weather. Repeatedly bringing a
           | rocket to the pad on launch day that's ultimately not flight-
           | worthy is different than scrubbing because of higher than
           | nominal cross winds.
           | 
           | And this case is particularly spectacular because while it's
           | ostensibly just a test, they are literally using the exact
           | same engines that the Space Shuttle used. Not as in the exact
           | model, but literally refurbished RS-25 engines that already
           | completed successful flights on the Space Shuttle.
        
             | Rebelgecko wrote:
             | Sure, STS-61c had 4 scrubs for mechanical issues. STS-71
             | had a similar ratio. So 4 mechanical scrubs on a semi
             | mature vehicle
        
         | koheripbal wrote:
         | Failure condition is an exploded rocket, not the number of
         | scrubs.
        
       | UberFly wrote:
       | The complexity is astronomical, so I'm glad they're being overly
       | careful. Once perfected I hope they keep up the cautiousness so
       | we don't start seeing shuttle-type neglect in the program.
        
       | newaccount2021 wrote:
        
       | the_third_wave wrote:
       | I assume this means the SRBs need to be disassembled to replace
       | the sealing between the segments seeing as how these were stacked
       | beginning in January 2021 [1] and the sealing is guaranteed for
       | 12 months. This has already been extended for 7-8 months but if
       | the launch is to be postponed until October or later they're
       | coming up to 2 years:
       | 
       |  _The joints connecting each piece of Space Launch System's five-
       | segment rocket motors are certified for one year once booster
       | stacking begins, a clock that began ticking Jan. 7 with the
       | hoisting of the SLS's left-hand aft center booster segment on top
       | of the booster's lowermost piece.
       | 
       | But the 12-month certification limit, a holdover from the space
       | shuttle program, could be extended with an engineering review,
       | according to John Honeycutt, NASA's Space Launch System program
       | manager at the Marshall Space Flight Center in Alabama.
       | 
       | Honeycutt said in January engineers planned to make measurements
       | and collect data as ground teams stacked each segment of the
       | Artemis 1 boosters inside the Vehicle Assembly Building. The data
       | could help NASA and Northrop Grumman extend the certification of
       | the rocket motor joints beyond 12 months.
       | 
       | "That gives us the best opportunity to do some sort of a life
       | extension on the booster stacking in the event that we need
       | that," Honeycutt said._
       | 
       | [1] https://spaceflightnow.com/2021/03/09/stacking-complete-
       | for-...
        
         | DougWebb wrote:
         | Yeah, it's not like NASA has ever had a problem ignoring their
         | own procedures when it comes to the seals on these kinds of
         | rockets...
        
           | jeffrallen wrote:
           | Those who do not learn from history are doomed to... blow up
           | their rockets?
        
         | gsibble wrote:
         | It's pretty clear they don't care at this point. They were
         | extended by 6 months and no one has brought it up since then.
         | NASA is feeling political heat to just fly this thing at any
         | cost at this point.
        
       | irrational wrote:
       | I feel like they need to go the SpaceX route and build dozens of
       | these things and just launch them with the expectation that most
       | will fail, but they learn from each failure to improve the next
       | ones.
        
         | jve wrote:
         | Not even SpaceX is going to test launch when there are obvious
         | issues.
        
         | jbay808 wrote:
         | Do you think they would have learned something worthwhile by
         | proceeding with the launch?
        
           | everybodyknows wrote:
           | The worst case would at least yield data from an
           | incontrovertibly true-to-life, no faking, test of the Launch
           | Abort System:
           | 
           | https://www.nasa.gov/image-feature/launch-abort-motor-for-
           | or...
        
         | quartesixte wrote:
         | Leak was on launch tower side, no?
         | 
         | 8-inch quick disconnect hoses have to be really gnarly to do
         | anything with.
        
       | thepasswordis wrote:
       | At this rate it seems really unlikely to me that the next mission
       | will have humans on it.
        
         | krisoft wrote:
         | Why?
        
         | gsibble wrote:
         | Agreed. I doubt the capsule part of the mission.....you know,
         | the actual mission.....will go smooth either.
        
       | cantaloupe wrote:
       | More discussion: https://news.ycombinator.com/item?id=32702211
        
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