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1 hour ago, michal.don said:

I should have made it clearer, I specifically meant the "largest thing we've tried to reenter" bit. Of course Starship would be much heavier when reaching LEO, but it seemed to me the reentering mass would be quite similar. But then again, in some cases the Starship might reenter and land with significant payloads (crew?) and become the heaviest thing ever reentered with significant margins.

Ah. The heaviest spacecraft at landing was STS-83 at 106.8t. The space shuttle remained roughly the same weight through re-entry to landing.

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20 minutes ago, RCgothic said:

Ah. The heaviest spacecraft at landing was STS-83 at 106.8t. The space shuttle remained roughly the same weight through re-entry to landing.

This was the Shuttle I wanted to look up (whatever brought down the largest mass). It's not impossible that some SS eventually gets fairly close to that with landing props included, I suppose—though as you said above, cargo SS mass will likely decrease if anything, not increase over time with this one being sort of heavy.

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2 minutes ago, tater said:

Maybe they will do a fit check for the QD arm?

That's what I believe too, but it should be after a while I think. First they gotta mount the claw to the QD arm and only then stack if they want to do that. If we believe all the info we have atm, the schedule should be:

- Completing the heat shield

- Mounting the Rvacs (all three raptor SL are mounted now, both ship and booster)

- Fit check with QD arm

- Destacking

- Air pressure test of both B4 and S20

- N2 WDR of both

- Static fire of the three S20 raptor SL, the three Rvacs, and the 29 B4 raptors

- Restacking, probably more cryo test and static fire(s)

- Launch

Edited by Beccab
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27 minutes ago, RCgothic said:

Starship may be capable of some downmass though

Its limited by heat shield, aerodynamic balance and header tank fuel for the landing burn. For now its not so much stuff to bring back. 
Yes you could recover satellites for repair but they are not that heavy. 

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Whats all that stuff exposed on the bottom of the booster?

 

Its weird not seeing any landing legs, making it look even more like a water tower. But all that exposed stuff on the bottom is.... for what? 

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50 minutes ago, MKI said:

Whats all that stuff exposed on the bottom of the booster?

 

Its weird not seeing any landing legs, making it look even more like a water tower. But all that exposed stuff on the bottom is.... for what? 

I think they are hydraulic accumulators.

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1 hour ago, MKI said:

Whats all that stuff exposed on the bottom of the booster?

 

Its weird not seeing any landing legs, making it look even more like a water tower. But all that exposed stuff on the bottom is.... for what? 

The large black cylinders are COPVs, which will have their aerocovers when it launches

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vGN8Xf3.jpgThese could be the new RCS system for B4, which would be repurposed depress vents

The booster load spreader is also apparently going up, we'll see if they can squeeze a lift today or if it is another day

Edited by Beccab
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21 minutes ago, tater said:

Yeah, I should have been clear I was talking about the flat stuff in between the COPVs.

Yes its lots of stuff on the outside, my guess is that they add an aerodynamic cover all around. 
Generally it looks a bit messy, piping up at various places. Why not add some raceways who would double as structural elements. 
On the other hand SS has none. Does it have overflow and pressurization pipes internally? They found that having an raceway to end the tiles would be to hot and internal pipes is also structural. 

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4 hours ago, RCgothic said:

Starship may be capable of some downmass though

You pay for capability.

Heavier structure, more landing fuel, etc.

So there is a question of whether to penalize all your other missions for the capability of downmass that you might never use. This is, after all, one of the longstanding complaints about the Space Shuttle design process -- it was designed for capabilities that were never actually used.

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27 minutes ago, Beccab said:

vGN8Xf3.jpgThese could be the new RCS system for B4, which would be repurposed depress vents

The booster load spreader is also apparently going up, we'll see if they can squeeze a lift today or if it is another day

Don't look lit it, my guess is cowers for cameras or other sensors. RCS would point out or sideways for roll. Up would be on top. 
Now it could be oxygen venting but the two are so different so probably two uses. 

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3 minutes ago, magnemoe said:

Don't look lit it, my guess is cowers for cameras or other sensors. RCS would point out or sideways for roll. Up would be on top. 
Now it could be oxygen venting but the two are so different so probably two uses. 

I doubt cameras, this is them without covers
SObKD7y.jpg

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2 minutes ago, mikegarrison said:

You pay for capability.

Heavier structure, more landing fuel, etc.

So there is a question of whether to penalize all your other missions for the capability of downmass that you might never use. This is, after all, one of the longstanding complaints about the Space Shuttle design process -- it was designed for capabilities that were never actually used.

This, now once you start getting production in space like optical fibers for long distance internet you can always make an starship variant who can handle landing with more payload. 
Larger fins for various loads and better at aerobraking, beefier heat shield and larger or two header tanks for landing heavier loads. 
You will get lots of variants. Guess the LEO tankers will be different from the ones refueling moonship at least down the line. 
Don't get started on manned ones. 
 

11 minutes ago, Beccab said:

I doubt cameras, this is them without covers
SObKD7y.jpg

So venting but the the covers are not something like an nozzle. On the other hand superheavy is so kerbal that Jeb is scared. 
Like the wiring in the photo in my above link. So much does not feel right with hypersonic. 
And they plan on catching the second first stage. 

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38 minutes ago, mikegarrison said:

You pay for capability.

Heavier structure, more landing fuel, etc.

So there is a question of whether to penalize all your other missions for the capability of downmass that you might never use. This is, after all, one of the longstanding complaints about the Space Shuttle design process -- it was designed for capabilities that were never actually used.

Don’t forget now, Starship’s primary purpose actually is downmass… on Mars. :D 

How well that translates to Earth, well, we’ll see. But I still keep slim hope that Starship will one day bring back the Hubble for the Smithsonian. :cool:

37 minutes ago, magnemoe said:

Don't look lit it, my guess is cowers for cameras or other sensors. RCS would point out or sideways for roll. Up would be on top. 
Now it could be oxygen venting but the two are so different so probably two uses. 

Ullage “thrusters”, maybe? B4 is still quite unfinished at this point, there’s a lot of covers still need to be put on. Or, SpaceX has done the modeling and figured out some stuff doesn’t actually need covers. Wouldn’t the shock wave itself keep hypersonic flow away from the hull to a point?

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11 minutes ago, CatastrophicFailure said:

Don’t forget now, Starship’s primary purpose actually is downmass… on Mars. :D 

How well that translates to Earth, well, we’ll see. But I still keep slim hope that Starship will one day bring back the Hubble for the Smithsonian. :cool:

 

More than that, the plan has always been to refuel them on mars and bring them back, with all the life support and amenities still installed. (and possibly with people who decide mars is not for them aboard.) That's going to require earth dowmass.

 

Point to point is also earth downmass, even though it's not going to be "up" for very long.

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17 minutes ago, CatastrophicFailure said:

Don’t forget now, Starship’s primary purpose actually is downmass… on Mars. :D 

I've said it before, but it's a ridiculous idea to use a Martian landing ship as an Earth LEO ferry. Horses for courses.

Developing technology that can be used on Mars? Fine. Actually designing your Earth LEO ships as Martian landers? Idiotic.

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