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The first launch of the Space Launch System [SLS]

The first launch of the Space Launch System [SLS]

The first launch of the Space Launch System [SLS]

(OP)
FYI ONLY...

If I have seen farther than others, it is because I have stood on the shoulders of giants." --Sir Isaac Newton

The first launch of the Space Launch System [SLS] live on August 29th, 2022! The launch is currently scheduled for 0833 AM USA-EST.

NASA's epic Artemis 1 moon mission launch is just 1 week away
https://www.space.com/nasa-artemis-1-mission-launc...

I'm getting that old 'tingle'... anticipation mixed with apprehension and awe and admiration and pride and 'wonder-how-heck'... as I did watching the Saturn 5 launches as a kid.

The Long Journey Beyond Reach: Saturn 5 Launch History
https://orbitaltoday.com/2022/05/16/the-long-journ...

Trivia... [before?] E.F. Bruhn wrote the first edition of the staggering Analysis and Design of Flight Vehicle Structures, he partially wrote and edited the [more obscure] book Analysis and Design of Missile Structures. E.F. Bruhn, J.I. Orlando, J.F. Meyers

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: The first launch of the Space Launch System [SLS]

it'll be great to see, for sure; but I think SpaceX have eclipsed them.

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

RE: The first launch of the Space Launch System [SLS]

Oh yeah I have a special wake-up call already set up for the day. I'm in a western time zone so activities will start early in the morning for me.

RE: The first launch of the Space Launch System [SLS]

Quote (rb1957)

but I think SpaceX have eclipsed them.
For sure.
I'm not sure NASA really knows how to do this now. They are good at building and operating probes to the planets and the Webb telescope is a marvel to be sure. This SLS has been a scheduling and financial debacle for a decade. There are serious problems with the ground support equipment and launch tower. Remember how poorly the rocket performed during the first wet test too. I've been expecting some type of problem to arise this week and won't be surprised to see it rolled back to the assembly building. If that happens, then I expect the SpaceX starship to launch first. That would probably kill the SLS program.
I hope I'm wrong and hope for great success. BUT- after following this program for years I really will be surprised if this thing ever launches a manned mission.

Brad Waybright

The more you know, the more you know you don't know.

RE: The first launch of the Space Launch System [SLS]

nah, SLS has support in Congress ... if they remove life support then things'll be different.

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

RE: The first launch of the Space Launch System [SLS]

(OP)
RB...

For a few extreme launch conditions, SpaceX has 'bit-the-bullet' and accepted loss of the first stage of launch vehicles... no landing gear, no grid-fins and full expenditure of fuel.

Also, the the super-sized SpaceX launch vehicle has yet to lift-off with all [33] stage-1 engines running. That cacophony of engines seems pretty sketchy/chancy to me. I figured that the first stage would/should have flown a typical launch profile, by now, with a throw-away dummy upper-stage.

But, hey... my SWAG... what do I know...?

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: The first launch of the Space Launch System [SLS]

yes, their new booster is a beast ! At 5000 tonnes, it is nearly double the Saturn V (3000 tonnes).

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

RE: The first launch of the Space Launch System [SLS]

I still think SpaceX is light years ahead of NASA, considering their accomplishments and available resources. As with Artemis, there are many concurrent activities involved with the Starship project. Aside from SpaceX efforts, government agencies, particularly the FAA have been slow completing the permitting process. The last environmental assessment was finished in late June after many delays. I believe this process still isn't complete, but does not yet seem to be delaying launch. Also, whether the first booster and ship is recovered for reuse, they are being built as such using nascent techniques. I'm still fascinated to watch 2 boosters land instantaneously within sight of each other. I can't wait to see a super-heavy booster recovery using the launch tower 'chopsticks'. SpaceX may be slightly behind schedule, and no idea about the state of their finances, but it's nothing like the overages that have defined the SLS.

Brad Waybright

The more you know, the more you know you don't know.

RE: The first launch of the Space Launch System [SLS]

(OP)
BTW... I always wondered why the base of launch vehicles [with engines, structure and guidance] wasn't separated from the tank-section... allowing the base-section to be recovered by parachute/flotation-bag for re-use... then repair/refurbish and install the base on another disposable 1st stage tank module.

A test case could have been tried years ago using the original Atlas design... which was a clever single stage to-orbit concept... with additions of the [2] booster engines/structure/fairings that fed from the core-tank... then separated from core booster/tank when no-longer needed... and the core engine pushed itself and the payload to orbit.

The core booster consisted of the center engine... which I think the was optimized for higher altitude... mounted to the tank tank-body with guidance.

The jettisoned booster section... could have had tested with a parachute recovery system and an ocean flotation system plus recovery beacons. DANG opportunity missed. This section was 'ripe' for re-use.

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: The first launch of the Space Launch System [SLS]

(OP)
Bard... SpaceX did not develop space-launch in a vacuum... they hired lots of old-timers from industry with experience... absorbed available technology and lit-a-fire under new eager-guns... then test-test-test. Failure was always an option... assuming vital lessons were learned.

SpaceX's progress is reminiscent of the early USAF missile development. For about 6-months in the 1950s, my dad was in Thor Missile training at Vandenberg AFB CA. Thor and Atlas were being built/tested/launched/tweaked from Vandenberg and Cape Canaveral ~1-X week.

I remember watching ascending missiles from VAFB... weekly. They were dead silent until the 'roar' finally reached-us miles away in Santa Barbara. My Dad couldn't call us... be he let Mom know the night before a launch 'when' to have us kids outdoors playing at a 'certain time'.

PS: Officer and Senior NCO wives [spouses] always know secret stuff... that is why they have clearances ~equal to their GI husbands [spouses].

PS: While working at Santa Maria CA airport, some of our friends worked at VAFB [just-over the low coastal mountains from SM] and would let us know when missile launches were happening. It was cool! One time a bunch-of-us saw a double Minuteman III 'salvo [war] launch'. Kinda pretty, kinda eerie, kinda scary experience.

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: The first launch of the Space Launch System [SLS]

I don't think we're saying SpaceX invented everything in a vacuum. But what they did was create an environment where things get done. Their achievements are truly stunning. I remember my own reaction when I heard about landing rockets ... "nuts!" and it took only very few misses before they nailed it. And now this "chopstick" thing ... "nuts !" (and I'll be proved wrong again!)

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

RE: The first launch of the Space Launch System [SLS]

NASA operates under the watchful eye of Congress, many members of which would rather skim off money for other things. Therefore, any time there is a failure those vultures are ready to pick NASA apart. NASA is stuck spending far more money to ensure that not one step has an unexpected outcome, which is terribly expensive in time and money. Worse, there aren't as many "learning" opportunities where engineers and makers get skilled at analyzing what is happening, so when problems do occur the organization isn't in such a good position to recognize the reach of the problem.

SpaceX doesn't have that restriction - recall their earlier, nearly comic, failures. So they get an organization that accepts the need to stop and fix problems as they occur rather than just barrel along.

Neither group is careless, but the NASA effort expends brainpower in trying to imagine everything that could possibly go wrong and SpaceX, having looked at only a smaller set of likely conditions, does more testing to see what does go wrong. This narrows the effort considerably at the cost of sometimes turning hardware into a scattering of fragments.

Since it has turned out that NASA could not, in fact, imagine everything that could possibly go wrong, it's clearly not an infallible strategy, in spite of the extra time and expense, but when they go to Congress they have piles of evidence that they had done everything they knew in order to fight off the vultures.

If Congress were to fund smaller steps in NASA programs, then Congress could also just pull the plug very easily. The extra funding and extra time is not a NASA initiated problem; it's a Congressional lack of consistency in support problem with funding and time being the symptoms of dysfunction in Congress.

A visible difference I attribute to the two methods is the exhaust plumes of the Saturn V engines vs the SpaceX engines. I think part of trying to imagine every failure is a tendency to make everything as perfect as possible. If nothing varies then nothing can vary too much.

Look at the transition where the darker shield gas layer is finally heated to incandescence on the Saturn V F-1 engine. That is about as steady a transition as one can expect - just a few percent variation it the distance from the nozzle exit.

SpaceX doesn't use that method, but the exhaust plume is noticeably more chaotic. I expect a large amount of money was spent on that near perfect performance on the F-1 engines.

The Saturn V transition is seen here: https://youtu.be/2cldgl9IIyY?t=345
The Falcon engine is seen here: https://youtu.be/976LHTpnZkY?t=24 and https://www.youtube.com/watch?v=D6mzGeXXn_A

They both work, but the F-1 is practically art and Falcon is git-er-done and the difference in price is obvious.

RE: The first launch of the Space Launch System [SLS]

I think describing the early SpaceX failures as "near comic" is more than a bit harsh. I agree that SpaceX's tolerance for turning test pieces into a "scattering of fragments" is much higher than NASA's, but part of that equation is what is to cost of imagining every possible failure (and missing some) in terms of dollars and schedule compared to the cost of a failed experiment ? As long as we're not killing people ...

And don't forget all SpaceX launches are licensed by the FAA ... so they're not completely uncontrolled cowboys.

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

RE: The first launch of the Space Launch System [SLS]

The FAA is concerned with having a place for the shrapnel to go and a way to ensure that the rocket becomes shrapnel rather than heading where it shouldn't. They don't review lines of code to ensure the engines operate correctly.

RE: The first launch of the Space Launch System [SLS]

This seems salient to this discussion--

Link

Brad Waybright

The more you know, the more you know you don't know.

RE: The first launch of the Space Launch System [SLS]

(OP)
NOTE to 'The bard', all: due to cybersecurity, when submitting a Link, please provide a brief subject/title relevant to the link.

As I recall, instability in the Saturn V F-1 engines, drove innovation towards stability in the F-1 and the SSMEs' with their god-awful million #-thrust engines'. AND having fewer engines resulted in lower potential destructive harmonics.

The Russians tried the use of many small engines for their 'moon-rocket'... and harmonics/instability destroyed all of the vehicles in 1st stage flight. Suggest You go-to Youtube search...
"Soviet N1 Moon Rocket \ The Largest Rocket we have forgotten".
'The Largest Rocket Explosion Ever - The Soviet N1 Moon Rocket Failure'

The brutal facts of today's world, are that that nationally-funded research is the foundation for basic knowledge and change-to-come... and is never cheap. What follows are innovators who take that hoard of hard-earned knowledge/experience and shape/reshape future.

NASA and the Russian Space agency have-had-to... and are-still... learning everything up-front. SpaceX and the all the other Space Agencies... India, Japan, China, PRK, etc... and component developers/contractors are the 'second mouse'**...

YES... BIG/EXPENSIVE/THROW-AWAY launch vehicles 'seem old fashioned'... but for super-sized payloads, the jury is out.

Regardless, SLS and SpaceX Starship... and their derivatives... must be fundamentally safe and reliable.##

***************
Anyway... I love quotes... I believe that these are relevant Fud-4-Thot... IE: perspective.

##"As a pilot, only two bad things can happen to you… and one of them (eventually) will.
a. One day you will walk out to the aircraft knowing that it is your last flight.
b. One day you will walk out to the aircraft not knowing that it is your last flight."
--Unknown

"Experience is one thing you can't get for nothing." -- Oscar Wilde

"In wisdom gathered over time I have found that every experience is a form of exploration." --Ansel Adams

"Experience is a brutal teacher, but you learn. My God, do you learn." --C.S. Lewis

"The early bird gets the worm, but the second mouse** gets the cheese." – unknown

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: The first launch of the Space Launch System [SLS]

(OP)
I can't believe I am even speculating this... but... I was looking at Artemis, and SpaceX Starship... stacked assemblies... and this random thought got 'stuck' in my brain...

I wonder if the Artemis 1st Stage Core booster... with SRBs... would be a 'similar-to-diameter' match for the SpaceX Starship Upper [payload/fly-back] stage?

IF the SpaceX Starship 1st stage gives them 'trouble' due to the huge number of engines... and IF the Artemis 1st Stage core and SRBs are highly reliable [although expensive]... could the 'two' be mated/flown' together?

I think I'll stop daydreaming and go back-to-work.

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: The first launch of the Space Launch System [SLS]

never ! the two companies and their philosophies would never allow a merger.

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

RE: The first launch of the Space Launch System [SLS]

Quote:

.. could the 'two' be mated/flown' together?
That's what payload adapters are for. "structural cone"

Keep on dreamin' Wil

RE: The first launch of the Space Launch System [SLS]

(OP)
SLS/Artemis 1st launch appears completely successful.
Next step is trans-lunar insertion 'burn'.
This is heady stuff!
https://www.space.com/nasa-artemis-1-moon-mission-...

more...
Translunar insertion is successful!
https://edition.cnn.com/2022/11/16/world/artemis-1...

Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov

RE: The first launch of the Space Launch System [SLS]

Re: WKTaylor, 25 August
I always wondered why the base of launch vehicles [with engines, structure and guidance] wasn't separated from the tank-section...

One word: Pogo

IIRC the Atlas had the worst pogo effect ever experienced by an astronaut. Not a concern for ICBM's.
If there's flexibility in the propulsion unit's coupling to the fuel tanks (center of mass) I can see the pogo effect taking over.

Sorry, it took a while for the coin to drop on your question...

Thinking about rockets a lot these days. I wonder why... ;)

RE: The first launch of the Space Launch System [SLS]

(OP)
SW... The Atlas core engine stayed with the booster to orbit... the 2-booster [side] engines were in a joined fairing/nacelle structure... that was jettisoned as a package. THAT BOOSTER PACKAGE is what should have been recovered.

Ho Hum... SLS has been a staggering success start to finish... with exception of 'anticipated' damage to the Launch-tower/gantry... mind boggling heat/sonic/over-pressures.

Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov

RE: The first launch of the Space Launch System [SLS]

Yes - a staggering amount of money and a staggering amount of time.

Still, nicely done even with the US Congress ready to meddle at the drop of a hat and change funding, goals, favored suppliers ... That's the heavy lifting that should be recognized.

RE: The first launch of the Space Launch System [SLS]

those side booster are "just" solid fuel cannisters. Shuttle recovered them. I suspect the learning was it's too much effort/cost to recycle, after they've been in the water.

a different learning might have been ... can we recover with a helicopter, like some other outfit (NZ ?) does.

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

RE: The first launch of the Space Launch System [SLS]

SpaceX' recovery system is one of the lessons learned from Shuttle, but having to reserve part of your fuel and carry extra weight are issues to consider. Additionally, once you actually reach orbital speed, coming back in is nontrivial

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

RE: The first launch of the Space Launch System [SLS]

(OP)
Rb... I am confused...

"Those side booster are "just" solid fuel cannisters...." HUHHH? For the original Atlas, these engines were liquid fuel and feed off the main tank... until shut-down, the then the 'Booster Package' separated [jettisoned]. After jettison, the core engine [designed for higher altitudes] pushed the tank [with remaining fuel/O2] to max V... sub-orbit or orbit depending on payload. This is why the Atlas was often called a 1-1/2-stage launch vehicle. Here is a brief history of this remarkable 'family' of launch vehicles...

How The Atlas Rocket Evolved Over 60 Years https://www.youtube.com/watch?v=TeGmIeu0xvI

Or were You referring to something else?

PS: The floor(s) of the ocean(s) away from Cape Canaveral and Vandenberg AFB are littered with tons US launch vehicle debris. I wonder if 'adversaries' ever used(use) stealth submarines to recover [or simply photo] debris for 'study? Hmmmmmm.

Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov

RE: The first launch of the Space Launch System [SLS]

'Adversaries' Wil? According to the previous POTUS, we're all 'friends'.

Anyone ever look into NERVA rocket engines?
Specific impulse = 841 seconds (vacuum)
The engines under the Shuttle / SLS are less than 500 seconds.

RE: The first launch of the Space Launch System [SLS]

NERVA - nuclear thermal rocket - not a good idea for terrestrial launch, you'll get a lot of NIMBYs complaining.

RE: The first launch of the Space Launch System [SLS]

(OP)
SpaceX Test of Starship 1st stage... 'all-engines'...

SpaceX's huge Starship booster conducts historic 31-engine burn (video)
https://www.space.com/spacex-starship-33-engine-st...

Apparently the ground crew aborted 1-engine just before all-ignition... and 1-engine self-aborted after ignition. BUT, SpaceX [Musk] deemed that the test was 'successful'.

Lighting off/running 33-engines at one moment... and for the duration of the boost phase... is a statistical 'crap-shoot'... which is why the SLS has only 4-liquid propellent high reliability [proven] 1st stage engines... and the [2] [proven] SRBs.

The Russians tried a similar clustered-small-engine arrangement in the 1960s on their moon-shot Rocket. It experienced vibration-overloads/harmonics, engine failures, etc... that destroyed each launcher shortly after lift-off.

During the Saturn 5 development tests [unmanned] the booster experienced high vibrations/surges/po-go, etc... that had to be 'tamed' [stabilized] before human flight. Still... every Apollo crew experienced a rough ride. I read somewhere that the Apollo 8 crew decided to be 'nonchalant' about describing their launch 'ride'... so that the next crews could 'experience in real-time' just how exciting... rough... the ride actually was. Yep.

Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov

RE: The first launch of the Space Launch System [SLS]

WKTaylor, Thank you for sharing this information, Wil. Indeed, testing such a complex and powerful system like the SpaceX Starship is challenging, and there is always a risk of failure. However, SpaceX's iterative design approach and their willingness to learn from each test will likely help them improve the reliability of their systems over time.

As you mentioned, vibration and harmonics can be a significant challenge for clustered engine arrangements. It will be interesting to see how SpaceX addresses this issue in future tests and designs.

Regarding your quotes, they all contain valuable insights. In science, beliefs should be based on evidence and empirical data, not personal biases or preconceptions. And while knowledge and understanding are crucial, humility and the willingness to learn and adapt are just as essential for scientific progress.

https://helenix.com/blockchain-security/

RE: The first launch of the Space Launch System [SLS]

(OP)
Max... I am particularly curious/disturbed as to why SpaceX has NOT had a full-duration 1st stage 33-engine Test... like often done at Huntsville or other rocket engine development facilities. Proof of the pudding. This was actually done with the 1st SLS booster... even though the [4] engines and the SRBs upgraded/recycled from the Space Shuttle.

Also WHY isn't SpaceX preceding the 'orbital test shot' with at least [1] development/launch sub-orbital test of the 33-engine 'recoverable' Booster stage with a dummy/throw-away upper stage.

But hey... The FAA is still in process of evaluating the Starship 'stack' for flight worthiness... with 'scant information... and are in no rush to issue a 'license' to fly. I'll be interesting to see when it REALLY launches.

Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov

RE: The first launch of the Space Launch System [SLS]

I don't expect to ever see a stationary, full duration test-fire of the 33-engine configuration booster. The launch pad at Boca Chica is just a stand on a flat concrete pad. Test firings cause damage to the pad and the damage obviously gets worse the longer the engines are firing. During a launch, the pad's exposure to the full force of the blast will be very short and diminish quickly as the rocket departs.
I do not know why SpaceX used this approach instead of a flame trench like NASA uses, but they're sticking with it.

Brad Waybright

The more you know, the more you know you don't know.

RE: The first launch of the Space Launch System [SLS]

(OP)
Interesting current perspective on SpaceX Starship and the launch-site changes in-work...

https://www.youtube.com/watch?v=U2ykt9JStao

Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov

RE: The first launch of the Space Launch System [SLS]

(OP)
A couple of interesting observations..

#1
Russian N-1 Moon launch vehicle 1960s. I was watching a launch video... noticed [4] relatively small 'Grid-Fin' panels at the base of the first stage... 90-Deg apart... Then the Booster thrust diminished, rolled-over and tumbled and exploded. Point I was making???... the Russkie's had Grid-Fins in the 1960s!!!!... while Saturn V relied on small-fixed fins attached to [4] outer-engine fairings.

#2
Was looking at a video of the SpaceX launch vehicle 1st stage. The body tank has thousands of reddish spots in lengthwise patterns up/down the SStl tank skin [pressurized to maintain shape while standing]. Then it hit Me squarely... the tank skin has internal lengthwise [hat or T] stiffeners that are likely spot welded to the skin... and the spot welds on the skin are corroding [rusting] in the salty air of south Texas seacoast. WOW... but then... as I understand it... the first few 'launch' 1st-stages are programmed to simple fall uncontroled into the ocean... no attempt to recover the stage. I presume that first stages will be studied for aerodynamic tendencies during the fall to help design recoverable stages.

In conclusion, Soooo... I guess the corroded spot welds are 'no sweat'. NOTE: corroded spot welds in SStl parts are notorious for failure in the long-term... and show 'hurried/sloppy... or NO... SW cleaning practices'.

Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov

RE: The first launch of the Space Launch System [SLS]

Many grades of stainless corrode very quickly after welding, so rust was my thought, too, when I saw so many regularly spaced brown spots on the booster. This was also evident in much earlier versions of the rocket. Remember the one that buckled under its own weight during assembly several years ago? I think it had the same rusty spots.

RE: The first launch of the Space Launch System [SLS]

(OP)
SpaceX Starship Flight #1 lifted-off was clean/smooth.

However 1st stage multiple [5 or 6???] engine failures probably lead to loss of control [cork-screwing] and disintegration before staging could occur, ~3:57 into launch.

It appears that SpaceX MAY have allowed the fight to proceed to vehicle 'break-up' and did not initiate self-destruct sequence.

https://www.space.com/spacex-starship-first-space-...
https://www.youtube.com/watch?v=0PPCP0ZDdUI

Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov

RE: The first launch of the Space Launch System [SLS]

A spectacular lift-off.
Watching 33 engine cones racing upward was beautiful and really feels SCI-FI.

I did notice several things:
There was a countdown hold just a minute before launching.
Several large pieces of debris thrown up before the rocket left the pad. Possible damage to the booster?
Some engines didn't light. More failed or were shut down partway up.
The engine status display on the telemetry didn't match the video.
It reached and then exceeded its separation altitude without separation.

I'm repeating stuff said by all the you-tubers, but when the stages couldn't separate for some reason, and maybe delayed after after several attempts to separate, the whole ship developed a tumble or a precession, making the separation a moot point and the mission couldn't proceed from the attitude the rocket was in.

Looking forward to the next launch.

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