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48 minutes ago, kerbiloid said:

Why build the catching tower before even having tested the first stage of the thing to catch?

What can go wrong?

What is the argument exactly? Are you expecting them to find out that they've actually built an oversized churro instead of a rocket and so the work on the tower is useless?
 

49 minutes ago, kerbiloid said:

Vibration test doesn't require the static fire.

They did it this way instead. Sure, you can do it without, and?
 

49 minutes ago, kerbiloid said:

Put more glue?

What if next time another tile unsticks?

There are various ways they attach tiles in places where there is more heating during reentry or that are less accessible. If it the vibrations are too high in a spot, they use the other methods

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9 hours ago, grawl said:

Those that held ok will probably keep holding, so no worries about them, those that got knocked off are replaced and thoroughly checked.

I disagree. If some actually came loose, that means there is a strong likelihood that others were weakened. It seems sensible to me that they will have to thoroughly check each one. 

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1 hour ago, mikegarrison said:

Wow.

That's definitely the nicest possible way I have ever seen of saying "either this attachment scheme or the quality control still needs some work". There is just no way that "parts falling off our flight vehicle" is "a feature".

I think, the point was that the  static fire is part of the quality contol scheme. Like, check your engines and your heat shield at the same time.

This obviously only works if the tiles that came loose were actually faultily attached in the first place. If we repeat the procedure and a whole different set of tiles comes down, the attachment method definitely needs improvement.

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16 minutes ago, Beccab said:

Are you expecting them to find out that they've actually built an oversized churro instead of a rocket and so the work on the tower is useless?

Yes.

16 minutes ago, Beccab said:
1 hour ago, kerbiloid said:

Vibration test doesn't require the static fire.

They did it this way instead. Sure, you can do it without, and?

And no need to spend an expensive full-featured thing when you can use a cheaper mockup.

17 minutes ago, Beccab said:

There are various ways they attach tiles in places where there is more heating during reentry or that are less accessible. If it the vibrations are too high in a spot, they use the other methods

Ares didn't.

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2 minutes ago, kerbiloid said:

And no need to spend an expensive full-featured thing when you can use a cheaper mockup.

I thought this was already a non functional mockup of the real thing that was definitely not starship?

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***

Looking at these tiles, I hope SpaceX provides good insurance to pay the dentist after the flight.

1 minute ago, Beccab said:

I thought this was already a non functional mockup of the real thing that was definitely not starship?

Why spend something beyond the exact test aim?

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3 minutes ago, kerbiloid said:

Why spend something beyond the exact test aim?

Because that’s slow, and ultimately more expensive.  You learn more from, ahem, integrated systems testing. Keep in mind, this isn’t the first time they’ve fired Starship with tiles attached. This has been an ongoing campaign since what, SN8? 9?

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9 minutes ago, kerbiloid said:

***

Looking at these tiles, I hope SpaceX provides good insurance to pay the dentist after the flight.

Why spend something beyond the exact test aim?

Ah, a mockup per test. Makes sense

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26 minutes ago, Minmus Taster said:

What went RUD? not S20 I hope

21 minutes ago, RealKerbal3x said:

Probably an engine at McGregor. I remember seeing stuff about an RVac RUDing a couple months back.

More info on the test, it was a Raptor 2 tested to set pressure levels at McGregor on the 23rd october. RUD occurred before reaching pressure levels but as Elon said, it's probably not a problem with the engine structure

(from the usual trustable spacex insiders)

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10 hours ago, CatastrophicFailure said:

Because that’s slow, and ultimately more expensive.  You learn more from, ahem, integrated systems testing. Keep in mind, this isn’t the first time they’ve fired Starship with tiles attached. This has been an ongoing campaign since what, SN8? 9?

This, booster 1-3 was mock ups. 4 is designed to fly but will ditch but they hope to try to catch booster 5, guess this depend on how 4 splashdown works out.
SN 20 will ditch, I guess SN 21, after this I expect starship to get its legs back and they will try to land them on islands in the pacific so they can inspect them properly. 

Ultimate goal is to catch starship with the chopsticks but this require overflying all of Texas. So you need successful reentries. 
As I understand they plan lots of suborbital flights to next year I assume this is trying to nail the transition from horizontal for maximum drag to vertical braking with an +-1 meter accuracy. 

How to optimize this is to have multiple road maps and adjust to how stuff unfolds. 

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7 minutes ago, magnemoe said:

booster 5, guess this depend on how 4 splashdown works out

6, not 5. 5 is maybe possible, but highly unlikely

The next 5 booster already have thrust pucks delivered now

 

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1 hour ago, StrandedonEarth said:

Assuming the usually glacial regulatory pace, once they get permission to fly they'll have lots of hardware ready to fly. Hopefully they won't run into any early lessons that force them to scrap existing hardware.

It won't matter much in the grand scheme of things because the point of these test articles is to find issues and scrap them. In fact, I'd be surprised if the next launch tower is a carbon copy of the first one.

Edited by Meecrob
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I guess maybe I should clarify. I don't think losing a few of these tiles off their test article was the end of the world or anything. This is why they do tests.

But what I was reacting to was the idea that this was a proper way to do quality control. "A feature, not a bug." That this was actually a good way to find improperly installed or damaged tiles.

No.

As a test to see if the tile process needs more work? Sure. But not as a good way to quickly inspect your tiles. It's not a "feature" when important parts of your vehicle fall off.

Edited by mikegarrison
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3 hours ago, mikegarrison said:

I guess maybe I should clarify. I don't think losing a few of these tiles off their test article was the end of the world or anything. This is why they do tests.

But what I was reacting to was the idea that this was a proper way to do quality control. "A feature, not a bug." That this was actually a good way to find improperly installed or damaged tiles.

No.

As a test to see if the tile process needs more work? Sure. But not as a good way to quickly inspect your tiles. It's not a "feature" when important parts of your vehicle fall off.

I agree, that was a bit of a stretch.

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...but we inspect planes with calibrated acceptable amounts of drips of fluids per time reference...

I guess what I am saying is count up the tiles that fell off, then count up the total tiles, calculate the percentage of failure, and please point me to a flight test program with this level of success.

Edited by Meecrob
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6 hours ago, mikegarrison said:

I guess maybe I should clarify. I don't think losing a few of these tiles off their test article was the end of the world or anything. This is why they do tests.

But what I was reacting to was the idea that this was a proper way to do quality control. "A feature, not a bug." That this was actually a good way to find improperly installed or damaged tiles.

No.

As a test to see if the tile process needs more work? Sure. But not as a good way to quickly inspect your tiles. It's not a "feature" when important parts of your vehicle fall off.

To clarify as well, my answer was an attempt at a lighthearted comment with a touch of humor.

In no way I believe it is a good idea to do QA on Starship this way. Final QA that is. But for a tile's laying process validation test ? Yes, of course.

I thought that was obvious. Darn, maybe I should have add some smileys.

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On 10/24/2021 at 2:38 AM, Deddly said:

I disagree. If some actually came loose, that means there is a strong likelihood that others were weakened. It seems sensible to me that they will have to thoroughly check each one. 

*Space Shuttle Flashback*

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Shuttle was mostly aluminum, not steel. Aluminum is amazing till about what? Mach 2.5ish? Someone better than me at thermodynamics/metallurgy help me out please! I'm going off of memory.

Edit: What I do know for sure is STS-27 lost a few tiles and made it back because the part that was exposed was steel structure, not aluminum.
https://en.wikipedia.org/wiki/STS-27

Edited by Meecrob
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Yes, steel has a higher melting point than aluminium, but I still expect that SpaceX will not be content with any tiles falling off in flight. People here are saying that the stresses of flight are probably less than the static fire because of the sound, hence my question - why don't they do the static fire before they attach the tiles?

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