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3 hours ago, Beccab said:

S24 at the same time will also have the final preparations for flight, like heat shield checks and replacements for instance. With this done, the path forward seems to be:

- 33 engine static fire

- restack

- final WDR

- launch!

How certain are we of a final WDR between the static fire and the launch? On the one hand, it can't very well hurt anything, but on the other hand, I'm not sure what risk you'd be retiring by doing it, unless they think that the static fire might produce structural issues for the booster that would show up during fueling.

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11 minutes ago, sevenperforce said:

How certain are we of a final WDR between the static fire and the launch? On the one hand, it can't very well hurt anything, but on the other hand, I'm not sure what risk you'd be retiring by doing it, unless they think that the static fire might produce structural issues for the booster that would show up during fueling.

Not 100% certain, but even if they passed it at first try I'd imagine they still would want to try it once again before really going for it to iron out the timing of the procedures

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2 hours ago, sevenperforce said:

How certain are we of a final WDR between the static fire and the launch? On the one hand, it can't very well hurt anything, but on the other hand, I'm not sure what risk you'd be retiring by doing it, unless they think that the static fire might produce structural issues for the booster that would show up during fueling.

Well they'll probably scrub the launch attempt at T-10 seconds at least once, and you can call that a WDR.

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13 hours ago, CatastrophicFailure said:

Its Texas, tho. Even the humidity is bigger. -_-

not as big as the humidity in southeast alaska. were technically a rainforest, but on an archipelago. 

Edited by Nuke
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So I read the follow up Twitter comments on the denting and they were… less than informative.

Anyone on here care to weigh in? I mean, to me that looks bad, maybe worse if the denting happens with every propellant loading, but how bad is it really? How does stainless steel handle that kind of mechanical working, for example?

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ever chug a beer so fast the can implodes?

anyway in flight the pressure decreases and so this probibly doesnt happen, and also i do believe that the pursuant is heated by the engines also helping maintain positive tank pressure during flight. i think this is just a ground testing artefact. of course since its steel and not aluminum, i dont think metal fatigue is as big of an issue. i would x-ray inspect the welds in the area though. 

Edited by Nuke
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1 hour ago, KSK said:

So I read the follow up Twitter comments on the denting and they were… less than informative.

Anyone on here care to weigh in? I mean, to me that looks bad, maybe worse if the denting happens with every propellant loading, but how bad is it really? How does stainless steel handle that kind of mechanical working, for example?

I happened to work for several years for the section of the DOT that deals with steel pipeline integrity.

As long as the "working" is within the tensile capabilities of the metal, there won't be any stress cracking in the metal and so it can handle a nearly unlimited number of cycles.

Consider a paperclip. You can use a paperclip to clip and unclip paper an endless number of times, and the paperclip is bending each time, but it's bending across a very small range that's well within its tensile capabilities. However, you can break a paperclip quickly if you unbend it all the way and then back again several times, because that amount of bending exceeds its tensile capabilities and starts to break down the grain of the metal.

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6 hours ago, sevenperforce said:

I happened to work for several years for the section of the DOT that deals with steel pipeline integrity.

As long as the "working" is within the tensile capabilities of the metal, there won't be any stress cracking in the metal and so it can handle a nearly unlimited number of cycles.

Consider a paperclip. You can use a paperclip to clip and unclip paper an endless number of times, and the paperclip is bending each time, but it's bending across a very small range that's well within its tensile capabilities. However, you can break a paperclip quickly if you unbend it all the way and then back again several times, because that amount of bending exceeds its tensile capabilities and starts to break down the grain of the metal.

For reference, it had also happened a couple times to SN15 back in the day, with no repercussions on the vehicle

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7 hours ago, sevenperforce said:

I happened to work for several years for the section of the DOT that deals with steel pipeline integrity.

As long as the "working" is within the tensile capabilities of the metal, there won't be any stress cracking in the metal and so it can handle a nearly unlimited number of cycles.

Consider a paperclip. You can use a paperclip to clip and unclip paper an endless number of times, and the paperclip is bending each time, but it's bending across a very small range that's well within its tensile capabilities. However, you can break a paperclip quickly if you unbend it all the way and then back again several times, because that amount of bending exceeds its tensile capabilities and starts to break down the grain of the metal.

That makes sense - thanks.

50 minutes ago, Beccab said:

For reference, it had also happened a couple times to SN15 back in the day, with no repercussions on the vehicle

That's also a good point but as the STS program found out to its sorrow;  'it happened last time so it's fine' isn't necessarily a great reason to carry on doing it.  

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