I understand the want, and I understand the desire to make the whole stack system more universal, but they're going to have to do something at this point.

I'm wondering if they're concerned with landing and turbulence/reflection on the diverter

My presumption was they would want to prove the vehicle can launch/land without something they can't have on the early trips to Mars

Yeah that's the 'want' I believe. The issue is they are going to have to destack/repave a crap ton of it after that 33 engine static fire, let alone what happens when it actually blasts off. Zero chance that martite holds up to that, even for a few seconds.

I thought the water table was too high for a flame trench.

They will not likely excavate downward to build a flame trench but they may build the implement above grade. The OLM at Boca is about 60' high. So I would expect that they will construct a flame diverted/diffuser along with a deluge system below the OLM but above grade. It will likely be a solution that can roll out of from under the OLM when they need to raise the maintenance platform.

As I understand it, the launch pads at KSC are built up and the flame trench is not below grade either. Likely for the same water table concerns. This is why the crawlers have that last hill to climb before reaching the launch sites in FL.

Mary's husband passed away

I will cherish all the wonderful memories of our life together but I will miss my husband terribly.
I want to thank the @NASASpaceflight family and our neighbors at SpaceX for their love, support and kindness through this difficult time. ❤️

— Mary (@BocaChicaGal) January 20, 2023

Kceovaisnt- said:

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They will not likely excavate downward to build a flame trench but they may build the implement above grade. The OLM at Boca is about 60' high. So I would expect that they will construct a flame diverted/diffuser along with a deluge system below the OLM but above grade. It will likely be a solution that can roll out of from under the OLM when they need to raise the maintenance platform.

As I understand it, the launch pads at KSC are built up and the flame trench is not below grade either. Likely for the same water table concerns. This is why the crawlers have that last hill to climb before reaching the launch sites in FL.

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Not just groundwater. You'd have to maintain pumps to clear out rainwater and leftover deluge water as well as deal with leaves, grass, and any other detritus. The test stands in Huntsville Alabama are all elevated and my guess is the ones in McGregor are as well

Some are very tall, some of them are horizontal still if I remember right.

Horizontal test stands seem to be the current favored development stands, just for the relatively low building cost.

Interesting.

I have been asked to evacuate ahead of today’s full WDR. Booster 7 and Starship 24 will be getting frosty. Road closure is from 8 am - 8 pm. 🤩🚀@NASASpaceflight pic.twitter.com/o0REQvP86h

— Mary (@BocaChicaGal) January 23, 2023

That's a huge next step for Starship. We are so close to a liftoff.

OKCAg2002 said:

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That's a huge next step for Starship. We are so close to a liftoff.

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So is this a static fire with full fill or just a full fill?

Ag_of_08 said:

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Some are very tall, some of them are horizontal still if I remember right.

Horizontal test stands seem to be the current favored development stands, just for the relatively low building cost.

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Not a rocket scientist by any means.... I suppose the vertical test stands allowed testing the engine knowing that flow conditions would be identical to the flow conditions on the vertical rocket. I guess advancements in 3D fluid modeling and better understanding/computational ability of fluid dynamics allows them to build horizontal test stands?

No doubt a horizontal test stand is much simpler to build.

I believe that a wet dress rehearsal is everything up to pushing the "button" for launch. They'll fill the entire vehicle with propellant and then empty it, roll it back to inspect, and evaluate. I assume the next step after this will be the full static fire.

OKCAg2002 said:

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I believe that a wet dress rehearsal is everything up to pushing the "button" for launch. They'll fill the entire vehicle with propellant and then empty it, roll it back to inspect, and evaluate. I assume the next step after this will be the full static fire.

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Exactly.

Quote:

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A wet dress rehearsal simulates every stage of a rocket launch without the rocket actually leaving the pad. A dry run, if you will. However, what makes the practice launch countdown a wet dress rehearsal is the act of filling the spacecraft's propellant tanks, resetting the countdown clock and draining the tanks.

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One day this will be a normal site. Today it is incredible.https://t.co/6wkCBPDBXx pic.twitter.com/pgNitYbNkY

— Michael Baylor (@nextspaceflight) January 23, 2023

https://twitter.com/considercosmos

That looks a little chilly.

Pretty solid article and video on the importance of cislunar.

https://www.nbcnews.com/science/space/space-earth-moon-get-little-crowded-rcna64333

will25u said:

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That looks a little chilly.

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Give new meaning to a "tall cool one"

She needs a fire up under her to keep her warm.

Sounds like it's about over.

Wow. Check out this before and after showing the significant compression of the booster while under full load of the Starship.

Edited by @DeffGeff
Credit🎥@Labpadre pic.twitter.com/cgVbBteEGC

— Zack Golden (@CSI_Starbase) January 23, 2023

Frost is coming down now. Detanking is confirmed to be underway! Looks like a great test.

— Michael Baylor (@nextspaceflight) January 23, 2023

So...did it all go well as indicated? Hopefully.

10 million pounds.

Today’s test will help verify a full launch countdown sequence, as well as the performance of Starship and the orbital pad for flight-like operations

— SpaceX (@SpaceX) January 24, 2023

Kenneth_2003 said:

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Ag_of_08 said:

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Some are very tall, some of them are horizontal still if I remember right.

Horizontal test stands seem to be the current favored development stands, just for the relatively low building cost.

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Not a rocket scientist by any means.... I suppose the vertical test stands allowed testing the engine knowing that flow conditions would be identical to the flow conditions on the vertical rocket. I guess advancements in 3D fluid modeling and better understanding/computational ability of fluid dynamics allows them to build horizontal test stands?

No doubt a horizontal test stand is much simpler to build.

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The main difference is how air might get trapped in the lines and also how the engine drains fluids after a test which is probably more relevant for Kerosene engines, where the other propellants (oxygen, Hydrogen, and recently methane) will evaporate quickly at ambient temperatures. Air pockets can be mitigated with forethought about the test vs launch orientation.

Most recent engine test programs use horizontal test stands. SpaceX, Blue Origin, Rocket Lab, Virgin Orbit, ABL, and many others use horizontal test stands.

Aren't SpaceX's certification test stands vertical though? The ones the actually test fire engines before putting them in service on.

Meanwhile, across the pond, Arianne 6 is very late (but nothing like SLS), and not remotely cost competitive with f9 as all have known for years, let alone potentially starship, so…they are blaming the ESA.

It sounds a lot like @ArianeGroup CEO André-Hubert Roussel is pointing to ESA oversight as being the reason that Ariane 6 is delayed. pic.twitter.com/9AvfUVQUmE

— Andrew Parsonson (@AndrewParsonson) January 24, 2023

He called it compression, but I think the better term would be thermal contraction

Ag_of_08 said:

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Aren't SpaceX's certification test stands vertical though? The ones the actually test fire engines before putting them in service on.

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I do not know for certain. I know raptor engine is run on horizontal test stands, not sure if they have a vertical one for Raptor pre-flight certification. Maybe Merlin engines are run vertically or maybe you're thinking of second stage testing.

I know for second stage certification vertical is more common while testing the whole integrated stage (with the tanks). But the second stage fires in a pretty different orientation anyway once already near space so the vertical firing may be more a test of the engine to tank integration than of the orientation, and the tank needs to be vertical to feed the engine properly.

They have both vertical and horizontical test stands at McGregor.

bthotugigem05 said:

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They have both vertical and horizontical test stands at McGregor.

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For Raptor engine too?

As far as I know, yes.

After completing Starship’s first full flight-like wet dress rehearsal, Ship 24 will be destacked from Booster 7 in preparation for a static fire of the Booster’s 33 Raptor engines pic.twitter.com/YXSfyBufmX

— SpaceX (@SpaceX) January 24, 2023

Turtles gonna be scurred.