Alaurentia proposes to build hovering capital city

a reply to: swanne

You also need a material that has been tested over time. Just because it works today, if you are using it for a structural purpose what will happen 10 years from now, will it's integrity become compromised.

a reply to: OccamsRazor04

Yeah, my thoughts exactly.

a reply to: swanne

It's a cool idea, but unless you are a city of only the ultra rich I would move on from this pipedream. The flying aspect is also troublesome. Would aviation agencies even let you fly it in their airspace?

a reply to: OccamsRazor04

Yeah, that's another issue. Unless Alaurentia owns its own airspace, that flying castle isn't going to fly. Literally.

The idea of partially cancelling out the weight of a building is a nice one, but I personally think it'd be simpler to build floating islands. If a city that's able to "move around" is the President of Alaurentia's goals, then why build it against gravity, when you can simply make it float?

a reply to: swanne

Not only is that doable it is actually being done. It's also expandable.

That's right.

a reply to: swanne

Too early to drink and I have a test to take later, so I will put that beer in the fridge for later.

a reply to: OccamsRazor04

Haha, fair enough mate.

The idea of cities in the air was floated [pun intended] by Buckminster Fuller with his Cloud Nine concept.

I think you'd do better floating around in international waters as every square inch of land and it's corresponding air space is occupied by other countries. It would be far easier from a number of perspectives than floating around claimed air spaces. One guy claimed an abandoned oil rig as his new country and it nearly worked.

a reply to: swanne

I'm thinking a bit of a BioShock Infinite influence myself.

originally posted by: swanne
I can personally confirm that Alaurentia has way more than one citizen. I am Alaurentian, I actually wrote the Constitution and I am a teacher there.

But this thread is not about Alaurentia, it's about the idea of a tower that could use aeronautical engineering. I just wanted to know if you guys think it's theoretically possible. Pure academical question, simple enough: can you make a tower lighter than air using Zeppelin-like structures, or are the laws of physics disagreeing?

Sure it is possible. Build a #load of zeppelins and tie them together and you would get a floating "city".

Now you'll probably want to use helium and not hydrogen for safety, which would make the whole thing rather expensive to build and maintain.

PS: You could as well just build a city in low earth orbit instead. Ask Musk he'd probably love to help you out, lol.

I would shoot for "neutral buoyancy" like a couple of airship designs do. No need for super exotic materials, just light and strong ones. Most likely carbon nanotubes would be involved somehow. Graphene, it if could be mass produced as full sheets or even full crystal platforms would work but we are not there yet in its production.

Of course, there is always metallic hydrogen but that does not exist... yet. But everyone sees that as "floating on water" not floating in air. But why not?

Then, there is always that US Navy patent on "lessoning gravity" for hybrid air/water space craft that guy designed. Then it would be like the things seen in China and Africa floating in the clouds! Just like the cover of the Boston albums!

Light and strong materials (carbon fiber reinforced with carbon nanotubes), helium filled bladders that can be inflated/deflated at will, creating a neutrally buoyant craft that could rise and sink like a submarine...

It could be done! I like the "make it look like the crystalline entity from ST:TNG" which shows, you don't have to think conventionally!

originally posted by: TEOTWAWKIAIFF
Light and strong materials (carbon fiber reinforced with carbon nanotubes), helium filled bladders that can be inflated/deflated at will, creating a neutrally buoyant craft that could rise and sink like a submarine...

It could be done with just slightly warm air; no need to helium.

As I mentioned in a post above, Buckminster Fuller proposed the idea more than 50 years ago an enclosed sphere city (probably enclosed by one of his geodesic spheres) that would NOT require helium, but just regular air with an ambient temperature of just maybe one degree higher inside the dome than outside.

If the volume of the sphered-city were large enough (he figured at least a half mile diameter), then the mass of the material inside the sphere (buildings and people) would be negligible relative to the large volume of air it encloses, which would make it float.

Bucky Fuller called his concept "Cloud Nine". He understood that this was just a concept, and that advances in material science would be needed to make it a reality -- but the point of his exercise was that the science and physics behind it were sound.

The Flying Cities of Buckminster Fuller

Excerpt from link above:

...but here's how Bucky proposed a Cloud Nine would work. A half mile (0.8 kilometer) diameter geodesic sphere would weigh only one-thousandth of the weight of the air inside of it. If the internal air were heated by either solar energy or even just the average human activity inside, it would only take a 1 degree shift in Fahrenheit over the external temperature to make the sphere float. Since the internal air would get denser when it cooled, Bucky imagined using polyethylene curtains to slow the rate that air entered the sphere. He wanted to build Cloud Nines and anchor them to mountains, or let them drift so their inhabitants could see the world. One of the more practical uses he proposed for them was as disaster sites for emergencies.

Also:
Can Cloud Nine be built?

Wikipedia - Cloud Nine (tensegrity sphere)

a reply to: Mach2

Yeah, but you can't fly a tropical island into space...so there's at least one drawback.

a reply to: Soylent Green Is People


So Kevlar is out.

Maybe graphene aerogel? Metal organic framework? You could use the MIT/NASA voxel technology, line the interior between two spheres (or giant Bucky balls! ) with non-permeable MOF, pump in some gas to even further reduce the weight (maybe even transfer heat to the air inside, instead of gas cooled, gas heated?), then pull off the neutral buoyant trick with the air inside the dome.

Huh? Doesn't sound so crazy after all! Thanks for link and the reading! Nice to see equations in as article asking real science questions and trying to answer them in a "real world" scenario!