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How do they plan to get 100 tons of cargo from atop the starship down to the surface of Mars? Do you use a crane? I mean, cranes are heavy, right?

hwillis 7y ago
Its a two stage rocket. The top bit separates. Cranes are far and away the lightest way to move something up and down. Wires are incredibly strong for their weight; five times stronger than normal mild steel. Thats due to the stress exerted when they are made affecting the crystal structure. Not only that, but tensile stress is the strongest mode in general. Structures holding up mass have to resist buckling from all directions. Tensile structures can use every bit of mass budget to hold force going precisely down. Not only that, but you dont need all of rhe structure to hold a crane up, since its just sticking out the side of the rocket. Not only that, but you dont even need a motor since you just need to slow things down a bit as they descend. Yes, they'll use a crane.
anonytrary 7y ago
I think you're getting downvoted because of your flippant tone, but I am also curious how the cargo would get on/off the ship.
- SECProto 7y ago
  Pop open a hatch, crank out your jib crane [1], use a long steel cable to lower loads down. Pay attention to weight distribution inside starship to ensure it doesn't tip over. [1] like this old-fashioned warehouse https://en.wikipedia.org/wiki/File:Pl_gdansk_zuraw_dlugiepobrzeze2006.jpg https://en.wikipedia.org/wiki/File:Pl_gdansk_zuraw_dlugiepob... or the more modern style https://www.acklandsgrainger.com/en/category/Jib-Cranes/Cranes-and-Festoon-Equipment/c/10826 https://www.acklandsgrainger.com/en/category/Jib-Cranes/Cran...
- ryanmarsh 7y ago
  I have no idea how anybody read that as flippant. It was a sincere question. I’m about done with this community.
hadlock 7y ago
Cranes aren't especially heavy. You would need a boom to extend 2x the maximum dimension of the cargo hatch, so probably 8 feet, out past the exterior skin, plus some dyneema or steel cable, plus a winch motor of some sort. Not 100 lbs but probably less than 1000.
Tepix 7y ago
Yes, a crane. Here's a pretty picture from Elon Musk's instagram account: https://www.instagram.com/p/BZm88uhg1yN/ https://www.instagram.com/p/BZm88uhg1yN/ The weight of the crane isn't a big factor, you open a hatch and lower stuff to the ground.
twic 7y ago
Elon's space ideas scrapbook will have a few of these pictures in: http://www.projectrho.com/public_html/rocket/embarking.php http://www.projectrho.com/public_html/rocket/embarking.php

hwillis 7y ago

Its a two stage rocket. The top bit separates. Cranes are far and away the lightest way to move something up and down. Wires are incredibly strong for their weight; five times stronger than normal mild steel. Thats due to the stress exerted when they are made affecting the crystal structure. Not only that, but tensile stress is the strongest mode in general. Structures holding up mass have to resist buckling from all directions. Tensile structures can use every bit of mass budget to hold force going precisely down. Not only that, but you dont need all of rhe structure to hold a crane up, since its just sticking out the side of the rocket. Not only that, but you dont even need a motor since you just need to slow things down a bit as they descend. Yes, they'll use a crane.

anonytrary 7y ago

I think you're getting downvoted because of your flippant tone, but I am also curious how the cargo would get on/off the ship.

SECProto 7y ago
Pop open a hatch, crank out your jib crane [1], use a long steel cable to lower loads down. Pay attention to weight distribution inside starship to ensure it doesn't tip over. [1] like this old-fashioned warehouse https://en.wikipedia.org/wiki/File:Pl_gdansk_zuraw_dlugiepobrzeze2006.jpg https://en.wikipedia.org/wiki/File:Pl_gdansk_zuraw_dlugiepob... or the more modern style https://www.acklandsgrainger.com/en/category/Jib-Cranes/Cranes-and-Festoon-Equipment/c/10826 https://www.acklandsgrainger.com/en/category/Jib-Cranes/Cran...
ryanmarsh 7y ago
I have no idea how anybody read that as flippant. It was a sincere question. I’m about done with this community.

hadlock 7y ago

Cranes aren't especially heavy. You would need a boom to extend 2x the maximum dimension of the cargo hatch, so probably 8 feet, out past the exterior skin, plus some dyneema or steel cable, plus a winch motor of some sort. Not 100 lbs but probably less than 1000.

Tepix 7y ago

Yes, a crane. Here's a pretty picture from Elon Musk's instagram account: https://www.instagram.com/p/BZm88uhg1yN/ https://www.instagram.com/p/BZm88uhg1yN/ The weight of the crane isn't a big factor, you open a hatch and lower stuff to the ground.

twic 7y ago

Elon's space ideas scrapbook will have a few of these pictures in: http://www.projectrho.com/public_html/rocket/embarking.php http://www.projectrho.com/public_html/rocket/embarking.php