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Blocky Spaceship Viability and Refueling Propellant On Earth-like Worlds


Spacescifi

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What does it have to do with spaceships? 

The answer is nothing, of course. Spaceships are not tin cans, despite you insisting they are. They need Whipple shielding and thermal protection just to deal with micrometeoroids, nevermind weapons fire. Tinfoil was good for Apollo as outer skin, not as anything structural. The very base of your argument is flawed. While I provided an excellent simulation software that allows you to explore spaceship design options, you provided nothing but uneducated opinions based on highly questionable book (about a highly questionable project, too) that you never even named. Any realistic spaceship hull is going to be a complex sandwich of radiation shielding, Whipple shielding and structural backplates. Even the ISS does that. A combat spacecraft will need an even more complex hull structure.

Oh, and you should have figured out that the "numbers" you want are impossible to calculate. Go find me a conversion rate of 1310s French livre to any modern currency, and you'll see the problem (or not, you tend to be blind to problems like that). The best you can do it a rough estimate based on comparing an item's price between then and now, which is exactly what I did. It's also perfectly irrelevant, and your idea with peasants fueling spaceships is ridiculous. 

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7 hours ago, Dragon01 said:

Spaceships are not tin cans, despite you insisting they are.

Small spaceships are exactly tin cans or a pack of tin cans.
Pressuirized volumes are much better when curved, you would know this if you ever made a simple calculation of thin envelopes, say for tanks.
Because the stress in general depends on two curvature radii, so a flat surface has both of them infinite, a cylinder has one of them infinite, a sphere has both finite.
So, the cylinder is the best compromise between strength and volume.

Of course, don't hesitate with bringing a real life sample of not curved pressurized spaceship, seaship, or submarine hull.

In technological sense, a small spaceship hull, like any another tank, is made of bended metal bands welded into a ring, then stacked and welded or in another way attached together.

The Apollo LEM is almost a truss covereed with foil, where "glat" and "curve" can hardly be distinguished, as it's a 3d mosaic, lol.

Bigger ships, like seaships can be only welded from many metal sheets attached to each other with edges and welded together.
In this case you both can not and need not distinguish between "flat" and "curved" because they anyway will be curved under some particular profile. Please, bring a sample of a rectangular sea/space/any ship.
Also any big ship hull should be strengthened in particular place, so it again can't be flat because it's a compromise between the surface and the ribs shapes.

So, your fantasies about the technological preferences are pure fantasies.

7 hours ago, Dragon01 said:

While I provided an excellent simulation software that allows you to explore spaceship design options

Please, forgive me if I ask to repeat the link which I can't find.
Of course if it's not a videogame again, like the last time it was, lol-lol.

7 hours ago, Dragon01 said:

you provided nothing but uneducated opinions based on highly questionable book (about a highly questionable project, too) that you never even named.

I will definitely not interfere with your own search for the sources, as it would be strange after your manners and "arguments".
But I'm now ensured that the captions "S...re" and "St...ts" tell  you nothing in the "space fighter" context, so you are even not aware of probably the only authorized project on the theme, but still keeping proposing your space battleships Yamato and vacuum helicopters.

7 hours ago, Dragon01 said:

Any realistic spaceship hull is going to be a complex sandwich of radiation shielding, Whipple shielding and structural backplates. Even the ISS does that. A combat spacecraft will need an even more complex hull structure.

A combat spacecraft will need a lot of ISP and thrust even to move with such structure.
You even don't see the difference between propulsion in a water and in a reactionleess medium. :(
You even didn't bring any simplest calculation of delta-V required for a spaceship compared to a battleship with its ~20 m/s speed and the water reaction or a battle tank with its 10 m/s speed and the ground reaction.
Please, study the v/u = ln(M/m) formula and do that before bringing futuristic sci-fi suggestions.

7 hours ago, Dragon01 said:

Even the ISS does that

Even the ISS does what? Its module is a cylindric aluminium can made of bended and welded aluminium sheets, covered with an insulation blanket, like it should be.
It doesn't have anything like a battle tank metal-explosive-metal-metal-ceramics-polymer-metal sandwich which is caused by other reasons.
(While I agreed, a dynamic armor on the ISS would be a thing, lol!)

7 hours ago, Dragon01 said:

Oh, and you should have figured out that the "numbers" you want are impossible to calculate.

Then what makes you to repeat with passion the XIX century fairy tales about villages, knights, and their armor?
(Btw no need to google, I had read this long before the google appeared).
Can you just take a number of armored persons in a late medieval army (knights, squires, armored infantrymen) and compare this to the village number, lol?
Don't forget that XVIII-XIX was a time of anti-feudal struggle, so any argument from that time should be checked, as they are 90% propaganda from both sides.

Of course, a royal parade equipment would cost like a village together will both kidneys from every peasant in it.
But most of the armored persons, including knights, were not so rich to spend a village to equip.
Jan Zhizhka (Czech, but doesn't matter) was plowing while still being a knight.
As you bring Polish history as a sample, can you remember that poem about noble Golota and his daughter?
A village-costing armor, lol?

So, I hoped that a well-informed person like you can clarify this question with actual numbers.
And you see, it's not me who started the medieval theme here.

7 hours ago, Dragon01 said:

Go find me a conversion rate of 1310s French livre to any modern currency

So, you didn't hear about the purchasing power parity,
and also don't know that there were no currencies in modern sense in Medieval, only ingots of metal certified with a stamp, so "conversion rate" makes no sense here.

How much would it cost in "bananas"?

7 hours ago, Dragon01 said:

The best you can do it a rough estimate based on comparing an item's price between then and now, which is exactly what I did

Indeed? So, how much "bananas" does an average village cost? How much a full armor does? In numbers, not in words.

7 hours ago, Dragon01 said:

and your idea with peasants fueling spaceships is ridiculous. 

Have you even read the thread?
Almost every my post is about uselessness of the medieval setting in spaceships, except if just4lulz.

Edited by kerbiloid
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9 hours ago, Dragon01 said:

What does it have to do with spaceships? 

The answer is nothing, of course. Spaceships are not tin cans, despite you insisting they are. They need Whipple shielding and thermal protection just to deal with micrometeoroids, nevermind weapons fire. Tinfoil was good for Apollo as outer skin, not as anything structural. The very base of your argument is flawed. While I provided an excellent simulation software that allows you to explore spaceship design options, you provided nothing but uneducated opinions based on highly questionable book (about a highly questionable project, too) that you never even named. Any realistic spaceship hull is going to be a complex sandwich of radiation shielding, Whipple shielding and structural backplates. Even the ISS does that. A combat spacecraft will need an even more complex hull structure.

Oh, and you should have figured out that the "numbers" you want are impossible to calculate. Go find me a conversion rate of 1310s French livre to any modern currency, and you'll see the problem (or not, you tend to be blind to problems like that). The best you can do it a rough estimate based on comparing an item's price between then and now, which is exactly what I did. It's also perfectly irrelevant, and your idea with peasants fueling spaceships is ridiculous. 

 

For now, why not just let him/her go?

 

He really is no where near as dangerous as these two guys, both infamous internet trolls. Who know each other and apparently get along more or less.

03trolls-600.jpg

03trolls.1-650.jpg

Back to topic, what if the spaceship wanted to refuel with liquid methane instead of liquid hydrogen on a medievel tech world?

I did some research and found that swampy areas and wetlands tend to have concentrated amounts of methane because of decaying vegetation.

 

Also, I do think it quite funny for scifi alens to show up in a story here and get out and start shoveling cow patties. Refueling is now a stinky job.

fertilizer-cow-manure-straw-heap-260nw-6

Edited by Spacescifi
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7 minutes ago, Spacescifi said:

 

Which more or less derailed the entire objective of this thread.

Well, when facts and numbers derail a theory, that's worse for facts and numbers.

P.S.
Not to accuse you in many threads started, I don't care much about that, but if every second thread is yours, why should others avoid posting there what they think if this is not what you exactly expect?

P.P.S.
That's not me who started the medieval theme.

Edited by kerbiloid
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5 minutes ago, kerbiloid said:

Well, when facts and numbers derail a theory, that's worse for facts and numbers.

 

Really after reconsideration, I still favor blocky outer hulls, but where the crew actually live inside would instead be hard sausage shaped modules (cylinders with blunt ends). Which will prevent any pressure on the outer hull, since outside the crew module, everywhere else inside the ship would be vacuum. Until they landed on an earth-like world and it was pressurized for breathing.

Edited by Spacescifi
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3 minutes ago, Spacescifi said:

I still favor blocky outer hulls, but where the crew actually live inside would instead be hard sausage shaped modules (cylinders with blunt ends). Which will prevent any pressure on the outer hull, since outside the crew module, everywhere else inside the ship would be vacuum. Until they landed on an earth-like world and it was pressurized for breathing.

"Hull", "pressurized envelope", "a set of external plates", that's what you are mixing. Would be nice to distinguish your description details more exactly.

Edited by kerbiloid
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8 minutes ago, kerbiloid said:

Well, when facts and numbers derail a theory, that's worse for facts and numbers.

P.S.
Not to accuse you in many threads started, I don't care much about that, but if every second thread is yours, why should others avoid posting there what they think if this is not what you exactly expect?

P.P.S.
That's not me who started the medieval theme.

 

Consider, what else hace you really to talk about?

The neverending number wars? Shower thoughts? SpaceX. Guessing what Russia's space program is up to?

Besides my threads, that is really all you've got here to play with on the regular.

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You see? The threads about humanoid aliens in bulky ships are the only place where I can touch the real science in argumented answers from specialists.

P.S.
"hulls", "pressurized envelopes", "external plates" still should be clearly distinguished if you ask a question.

Say, a Star Destroyer doesn't need a pressurized outer hull, it's not Yamato.

Edited by kerbiloid
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2 minutes ago, kerbiloid said:

You see? The threads about humanoid aliens in bulky ships are the only place where I can touch the real science in argumented answers from specialists.

P.S.
"hulls", "pressurized envelopes", "external plates" still should be clearly distinguished if you ask a question.

Say, a Star Destroyer doesn't need a pressurized outer hull, it's not Yamato.

Are you saying you go to my threads specifically to argue your POV with others?

Well... that is what you have been doing, although you do not always find those who are willing to argue back.

But when you do, it can and does derail threads.

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3 minutes ago, Spacescifi said:

Are you saying you go to my threads specifically to argue your POV with others?

I am saying I don't care at all, who is the thread starter.
So, that's a Monte-Carlo: the more threads you start, the more of them I visit. Pure mathematics.

Edited by kerbiloid
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6 hours ago, Spacescifi said:

 

Which more or less derailed the entire objective of this thread.

The title of this thread includes "refueling on Earthlike worlds".  There are two "Earthlike worlds" remotely within reach: Mars and Venus.  Refueling on Mars is a known issue (details of difficulty are of course unknown), refueling on Venus would be pointless.  Worlds around other star systems are so difficult to reach and would require such unknown engines to make the thread pointless.

Blocky/non-blocky entirely depends on the standard size of material available vs. size of the hull.  Since steel is made in sheets much smaller than the size of a hull, nobody ever considers making a blocky ship: it would cost  just as much (well more steel means more materials cost and more welds so it would cost even more) and be less effective in everyway.  Something the size of a car can have each panel stamped (hydroformed) to shape (instead of being welded from little panels) and thus are a bit more blocky than might be optimal for their function.  Racecars and general aviation planes might be of similar size, but often are built as a monocoque for strength-weight efficiency (but harder to manufacture).

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10 hours ago, Spacescifi said:

Really after reconsideration, I still favor blocky outer hulls, but where the crew actually live inside would instead be hard sausage shaped modules (cylinders with blunt ends). Which will prevent any pressure on the outer hull, since outside the crew module, everywhere else inside the ship would be vacuum. Until they landed on an earth-like world and it was pressurized for breathing.

You don't need to pressurize anything, actually (besides the crew section, of course). Just leave the external hull open, so that it is always at the pressure of the surrounding. That way, you can only have it deal with dynamic pressure (that is, aerodynamic stress), and with heat, which it should be designed to withstand, anyway. 

If your world has an atmosphere and you have a thermal nuclear or fusion engine, you can avoid using propellant to land and take off (though you'll need it for deorbit and orbital insertion), by simply sucking air into the engine and using that. Obviously, intakes are dead weight in space. In most cases, it's probably too much trouble. Better collect ice from asteroids, or skim air off the atmosphere. 

3 hours ago, wumpus said:

Blocky/non-blocky entirely depends on the standard size of material available vs. size of the hull.  Since steel is made in sheets much smaller than the size of a hull, nobody ever considers making a blocky ship: it would cost  just as much (well more steel means more materials cost and more welds so it would cost even more) and be less effective in everyway.  Something the size of a car can have each panel stamped (hydroformed) to shape (instead of being welded from little panels) and thus are a bit more blocky than might be optimal for their function.  Racecars and general aviation planes might be of similar size, but often are built as a monocoque for strength-weight efficiency (but harder to manufacture).

Do note that if you have a very complex structure for the hull plating, it may be advantageous to produce it in a series of relatively small, interchangeable tiles. Whipple shields, in particular, need to be easily replaceable, because they are sacrificial protection. That was my original point, and it favors blocky hulls, because you need less kinds of tile. Everyone here seems to be thinking cars or aircraft (or tin cans), but large ships and especially warships will warrant a more complex hull design. At current spacecraft lifetimes, Whipple shield wear is not a major concern, but it might be so in the future, and obviously warships would be particularly subject to it. 

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10 hours ago, wumpus said:

The title of this thread includes "refueling on Earthlike worlds".  There are two "Earthlike worlds" remotely within reach: Mars and Venus.  Refueling on Mars is a known issue (details of difficulty are of course unknown), refueling on Venus would be pointless.  Worlds around other star systems are so difficult to reach and would require such unknown engines to make the thread pointless.

 

The point is in my name. Space science fiction. I am really asking could a scifi spaceship refuel coming to Earth, processing cow patties (poop) for liquid methane? Would it be worth it? Or are other liquid fuels easier to process on Earth?

I know the limits of modern technoigy, so this is allowing for FTL/warp and a means to neutralize gravity's pull so that rocketry to space SSTO scifi spaceships are suddenly viable.

5 hours ago, Dragon01 said:

You don't need to pressurize anything, actually (besides the crew section, of course). Just leave the external hull open, so that it is always at the pressure of the surrounding. That way, you can only have it deal with dynamic pressure (that is, aerodynamic stress), and with heat, which it should be designed to withstand, anyway. 

If your world has an atmosphere and you have a thermal nuclear or fusion engine, you can avoid using propellant to land and take off (though you'll need it for deorbit and orbital insertion), by simply sucking air into the engine and using that. Obviously, intakes are dead weight in space. In most cases, it's probably too much trouble. Better collect ice from asteroids, or skim air off the atmosphere. 

 

Only on an Earth clone alien planet there are legitimate reasons for keeping your outer hull closed.

Wild animals? Natives? That kind of thing.

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On 10/22/2019 at 3:21 AM, Spacescifi said:

Only on an Earth clone alien planet there are legitimate reasons for keeping your outer hull closed.

Wild animals? Natives? That kind of thing.

Closed doesn't mean pressurized. You can (and should) keep the gaps in armor very narrow. 

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