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11 minutes ago, YNM said:

If it's taller than everything in Houston or Dallas/Fort Worth then that's pretty crazy. But yeah that goes right.

They probably characterize South Texas as something south of the road between Houston and San Antonio. That or Corpus Christa and south. Not Houston, though.

Yeah, taller than the tallest in Corpus Christi. That's probably "south Texas."

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Just now, tater said:

They probably characterize South Texas as something south of the road between Houston and San Antonio. That or Corpus Christa and south. Not Houston, though.

Yeah, hence I said the 'south' part makes it more sensible.

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This is from December, but got posted on NSF.

Musk specifically mentions getting Starship well below 100 tons, and that as needed, they could stretch the tanks to up to 2000t of props (vs nominal 1200t).

 

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2 hours ago, southernplain said:

Everything is bigger in Texas.

This reminds me of when I was working for GE in Massachusetts. The woman who sat next to me was from Texas, and liked to talk about how much bigger Texas was than New England. So one day I decided to talk about my relatives who live in Alaska.

There was no talk about about how big Texas is for a while....

Edited by mikegarrison
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I live in Texas, so I guess I can point out that when we say "South Texas" around here, we're not including DFW. Just the southern coastline and the grasslands down there. West Texas happens when you get to the desert-y, arid areas, and the mountains, and East Texas is where all the pine trees are. DFW falls in Central Texas, and boundaries get fuzzy around the Panhandle.

That stuff about lightening Starship is interesting. The idea that it could do even better than promised... Nuts!

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5 hours ago, SOXBLOX said:

I live in Texas, so I guess I can point out that when we say "South Texas" around here, we're not including DFW. Just the southern coastline and the grasslands down there. West Texas happens when you get to the desert-y, arid areas, and the mountains, and East Texas is where all the pine trees are. DFW falls in Central Texas, and boundaries get fuzzy around the Panhandle.

That stuff about lightening Starship is interesting. The idea that it could do even better than promised... Nuts!

Spoiler

I know that this is off-topic, but as a Texan myself I cannot resist sharing this

 

On-topic, what is the current dry mass for early articles? I see 120 tonnes listed as a target, and an Elon Tweet says ~200 tonnes, but that's from almost 2 years ago (Sept 2019).

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E3o-7nsVIAEWmAQ?format=jpg&name=4096x409

 

8 hours ago, Silavite said:

On-topic, what is the current dry mass for early articles? I see 120 tonnes listed as a target, and an Elon Tweet says ~200 tonnes, but that's from almost 2 years ago (Sept 2019).

Using a metal weight calculator (a metal company page), I am guessing the mass is actually maybe 45t?

25 rings 9m in dia (6ft tall rings—the steel is sold in 6ft width), 4mm thick is 41.5t, so I slopped it upwards a few. More? 50t?

https://www.twmetals.com/resources/calculators.html

 

Edited by tater
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8 hours ago, Silavite said:
  Reveal hidden contents

I know that this is off-topic, but as a Texan myself I cannot resist sharing this

 

On-topic, what is the current dry mass for early articles? I see 120 tonnes listed as a target, and an Elon Tweet says ~200 tonnes, but that's from almost 2 years ago (Sept 2019).

The "starship Battleship", aka mk-1 that was built welding metal squares toghether weighted 200 tons, new ships are around 120 tons both from Elon and from guesstimate maths

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5 minutes ago, YNM said:

Do they use stiffeners (?) like in the skirt of the test SN's (??)

They have some baffles visible in some of the wrecked/scrapped parts.

I have to admit, I was honestly surprised at how low that value was.

Again, a total guestimate, but mess with that calculator. Even adding a fair bit of incidental mass, it's just not that bad. Heck, double the mass and it's only ~80t.

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44 minutes ago, tater said:

Heck, double the mass and it's only ~80t.

Nah I'm just surprised on the 4 mm part. To be fair they have internal pressures and stuff*. Most static structures don't.

 

*EDIT : the internal pressure resists buckling.

Edited by YNM
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25 minutes ago, YNM said:

Nah I'm just surprised on the 4 mm part. To be fair they have internal pressures and stuff. Most static structures don't.

4mm is the thick steel, there was talk about trying 3mm to reduce mass. The various pictures of rolls being delivered have the thickness on the sheets attached to them by the manufacturer so we know that value.

 

If they stretch the tanks a little (make the crew volume a little lower), LSS can fly a round trip from LEO with no aerobraking if fully tanked. And I am assuming an 80t LSS, not 50. With 20t of cargo on top of that.

No need for Orion, then. Load crew from Dragon/Starliner in LEO. Go to Moon, come home, back to capsule for EDL.

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16 minutes ago, tater said:

If they stretch the tanks a little (make the crew volume a little lower), LSS can fly a round trip from LEO with no aerobraking if fully tanked. And I am assuming an 80t LSS, not 50. With 20t of cargo on top of that.

No need for Orion, then. Load crew from Dragon/Starliner in LEO. Go to Moon, come home, back to capsule for EDL.

Yeah if they get SH up and running for LSS it's honestly a no-brainer to mess things with NRHO instead. Just go from LEO dock, straight landing, get back to LEO. Might even use the ISS ? We wouldn't even need Gateway or any sort of cislunar station...

Either that or kessler syndrome first, not sure.

Edited by YNM
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Just now, YNM said:

Yeah if they get SH up and running for LSS it's honestly a no-brainer to mess things with NRHO instead. Just go from LEO dock, straight landing, get back to LEO. Might even use the ISS ? We wouldn't even need Gateway or any sort of cislunar station...

or Orion.

 

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19 minutes ago, tater said:

No need for Orion, then. Load crew from Dragon/Starliner in LEO. Go to Moon, come home, back to capsule for EDL.

The worst part is that exactly because it makes Orion irrelevant it's unlikely to happen soon unless spacex decides to start lunar mission without nasa, just like the Apollo mission structure (three man capsule etc) killed the less expensive direct ascent lunar gemini and more recently Shuttle with, well, about any crewed project that wasn't Shuttle

Edited by Beccab
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2 minutes ago, Beccab said:

it's unlikely to happen soon unless spacex decides to start lunar mission without nasa

Honestly seems like you could do it with Dragon and LSS on MEO/HEO maybe ? They want all the starship tech they're planning for anyway (most important of which is refuel), NASA pulling the plug doesn't change anything for them.

Edited by YNM
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Just now, Beccab said:

The worst part is that exactly because it makes Orion irrelevant it's unlikely to happen soon unless spacex decides to start lunar mission without nasa, just like the Apollo mission structure (three man capsule etc) killed the less expensive direct ascent lunar gemini and more recently Shuttle with, well, about any crewed project that wasn't Shuttle

I think it comes for the ride with LSS. Also makes the first, uncrewed test flight SpaceX committed to interesting. Instead of a kind of boilerplate LSS that gets chucked (still possible), they make a flight article LSS, and land that "all up" as their demo.

They fly it back to LEO. They don't even have to build a second one.

1 minute ago, YNM said:

Honestly seems like you could do it with Dragon and LSS on MEO/HEO maybe ? They want all the starship tech they're planning for anyway (most important of which is refuel), NASA pulling the plug doesn't change anything for them.

Yeah, we've discussed this here before. @sevenperforce did some math on it as well in terms of using Dragon to deliver crew. The difference was that he was using what we know about regular SS (1200t props).

A slight tank stretch makes a huge difference in that math, however.

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3 minutes ago, tater said:

A slight tank stretch makes a huge difference in that math, however.

Once you're in orbit, you're already halfway to anywhere else...

Edited by YNM
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1 hour ago, tater said:

 

If they stretch the tanks a little (make the crew volume a little lower), LSS can fly a round trip from LEO with no aerobraking if fully tanked. And I am assuming an 80t LSS, not 50. With 20t of cargo on top of that.

No need for Orion, then. Load crew from Dragon/Starliner in LEO. Go to Moon, come home, back to capsule for EDL.

Sounds just like the real STS.

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