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1 minute ago, tater said:

That tweet suggests another on top of that? Is a section 9 under construction?

No, it means there are two orbital launch sites planned at Boca! 

 

Although I do actually think there's a good chance of a Hammerhead crane stacking on top of level 8.

Edited by RCgothic
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16 minutes ago, tater said:

That tweet suggests another on top of that? Is a section 9 under construction?

Section 8 is split into two parts, this one (8A) that is 2/3 as high as a normal section and soon 8B which is 1/3 we high as a normal section

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On 7/17/2021 at 12:44 PM, wumpus said:

Note that this largely applies to resusable vehicles.  Most early rockets (including Sputnik) were 1.5.  2.5 makes a lot more sense, but still requires an additional engine, controls, etc and lighting the engine in vacuum.

The safety concerns (for crew, etc.) apply primarily to reusable vehicles, yes. But 1.5 is still a bad idea even for expendables because you are taking so much dry mass to orbit. Look at Long March 5 and its whole out-of-control stage debacle.

2.5 stages is much more efficient. Atlas V, almost all Semyorka-derived rockets, the Delta IV Medium family...it's just an all-around good design.

 

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3 minutes ago, sevenperforce said:

The safety concerns (for crew, etc.) apply primarily to reusable vehicles, yes. But 1.5 is still a bad idea even for expendables because you are taking so much dry mass to orbit. Look at Long March 5 and its whole out-of-control stage debacle.

2.5 stages is much more efficient. Atlas V, almost all Semyorka-derived rockets, the Delta IV Medium family...it's just an all-around good design.

 

Efficient, yes.  But igniting those rocket engines is tricky.  Moreso in flight and after flight through a freezing atmosphere.  You only go to 2.5 if and only if you can absolutely light that upper candle or are using hypergolics.   (Most of my anti-hypergolic rants are for lower stages, not the top.  The poison is meaningless without considering the dosage), but I think hypergolics were developed at around the same time effective upper stage lighting became a thing.

Are there safety concerns if your 1.5 stages put you where you are firing your engines horizontally?  I'd assume (mostly thanks to KSP, no experience with the reality) that you could jettison your spacecraft if the upper stage failed to ignite and come down more or less as planned (either in the Atlantic or Siberia), and hopefully somebody bothered to put a ship/helicopter nearby.

Yes, the Chinese should be embarrassed for still using it.  But I wouldn't blame a microrocket startup for using this scheme, and I think it was where we ended in the great "KSP forum designed paper orbital rocket" thread.

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5 minutes ago, wumpus said:

Are there safety concerns if your 1.5 stages put you where you are firing your engines horizontally?  I'd assume (mostly thanks to KSP, no experience with the reality) that you could jettison your spacecraft if the upper stage failed to ignite and come down more or less as planned (either in the Atlantic or Siberia), and hopefully somebody bothered to put a ship/helicopter nearby.

The biggest safety concern, I think, is black zones for ballistic-trajectory aborts. That's why they had to put two engines on the Centaur for Starliner; the usual lofted trajectory used by Atlas V would result in too violent a re-entry if they had to abort near or after the end of the core burn.

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Will they do a full static fire of all 29-33 engines? I thought there was concern about pad damage.,.,

Regardless, whenever they do fire them all up, I think they should be playing this song. Heck, Musk should be in this getup, lol

Spoiler

 

 

Edited by StrandedonEarth
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18 minutes ago, StrandedonEarth said:

Will they do a full static fire of all 29-33 engines? I thought there was concern about pad damage.,.,

Probably like FH, they'll want to make sure their firing order is good.

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1 hour ago, StrandedonEarth said:

Will they do a full static fire of all 29-33 engines? I thought there was concern about pad damage.,.,

Regardless, whenever they do fire them all up, I think they should be playing this song. Heck, Musk should be in this getup, lol

  Reveal hidden contents

 

 

I prefer:

Spoiler

 

 

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4 hours ago, StrandedonEarth said:

Will they do a full static fire of all 29-33 engines? I thought there was concern about pad damage.,.,

  Hide contents

 

 

I'd be surprised if they did 9 on a suborbital pad, but who knows.

Orbital launch pad will be able to take the full 33.

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Just now, Minmus Taster said:

More tower segments? I thought they were done!

This bit is probably just going to be topping off the tower, probably with a roof and lightning rod.

The tower's structure is close to complete, but there's still a lot to add for it to actually function as a launch tower. Arms for fuelling the vehicle (and catching the booster in the future) and wiring still need to be installed.

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Cool shot. Evidently they're laying electrical lines, etc.

2047104.jpg

Reminds me a little of the Saturn IB milkstool. It was high enough up that IIRC it didn't need any water deluge at all to avoid damaging sound reflection off the ground, although it did use a flame diverter. Of course, the Saturn IB was about 9% the thrust of Superheavy.

Hard to imagine how Superheavy will be able to NOT get ripped apart by sound waves without a deluge.

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