4 ms·

I thought the air density might have been a mistake, but I checked and your numbers are correct. Theoretically, it should float, right?

by dmak 15y ago

deleted 15y ago
[deleted]
ars 15y ago
If you put a vacuum in it and shrink wrapped it it would float. But I don't know if the material is strong enough to result air pressure if it was shrink wrapped (i.e. would the air pressure squish it?)
- pyrhho 15y ago
  So, basically, it would be ideal for building a zeppelin. Put a bunch of it into a container, and evacuate it to go up. Fill the container with air again to go down. Nothing flammable to explode. Awesome.
  - Retric 15y ago
    It's still heavy compared to helium gas. Air is 1.2 kg/m^3 helium is 0.164 kg/m^3 and this stuff is .9kg/m^3
    - TylerE 15y ago
      Of course, if this could be used for large portions of the structure, that really changes the equations a lot. You don't need nearly as much lift for a given weight of cargo. The Hindenburg used 200,000m^3 of hydrogen (generating a lifting force of approx. 215,000kg. Net useful load was only 10,000kg.
      - Retric 15y ago
        When selecting materials for building aircraft weight is only one of many concerns. Durability, flexibility, strength, cost, etc are all major issues. Considering the design goals for this material seem to primarily just be weight I would be surprised if it's strength to weight ratio was impressive enough to overcome cost issues. Also compared to a modern blimp the Hindenburg an ancient design that's been far surpassed. A modern Zeppelin is much closer to 20% lift to weight ratio than 5 for the Hindenburg despite using less efficient helium gas. Their maximum permitted takeoff weight is 10,690 kg, with a payload of 1,900 kg.(http://en.wikipedia.org/wiki/Zeppelin_NT http://en.wikipedia.org/wiki/Zeppelin_NT)
- redwood 15y ago
  Strength is the key part they didn't mention. DARPA probably wants that bit for themselves :) However one must assume this has some strength, otherwise what would the point be. Very cool stuff
  - caf 15y ago
    DARPA might well be funding the research for the possibility of a future alternative to FOGBANK in nuclear weapons, which isn't as dangerous to produce.

I thought the air density might have been a mistake, but I checked and your numbers are correct. Theoretically, it should float, right?

by dmak 15y ago

I thought the air density might have been a mistake, but I checked and your numbers are correct. Theoretically, it should float, right?

deleted 15y ago

[deleted]

ars 15y ago

If you put a vacuum in it and shrink wrapped it it would float. But I don't know if the material is strong enough to result air pressure if it was shrink wrapped (i.e. would the air pressure squish it?)

pyrhho 15y ago
So, basically, it would be ideal for building a zeppelin. Put a bunch of it into a container, and evacuate it to go up. Fill the container with air again to go down. Nothing flammable to explode. Awesome.
- Retric 15y ago
  It's still heavy compared to helium gas. Air is 1.2 kg/m^3 helium is 0.164 kg/m^3 and this stuff is .9kg/m^3
  - TylerE 15y ago
    Of course, if this could be used for large portions of the structure, that really changes the equations a lot. You don't need nearly as much lift for a given weight of cargo. The Hindenburg used 200,000m^3 of hydrogen (generating a lifting force of approx. 215,000kg. Net useful load was only 10,000kg.
    - Retric 15y ago
      When selecting materials for building aircraft weight is only one of many concerns. Durability, flexibility, strength, cost, etc are all major issues. Considering the design goals for this material seem to primarily just be weight I would be surprised if it's strength to weight ratio was impressive enough to overcome cost issues. Also compared to a modern blimp the Hindenburg an ancient design that's been far surpassed. A modern Zeppelin is much closer to 20% lift to weight ratio than 5 for the Hindenburg despite using less efficient helium gas. Their maximum permitted takeoff weight is 10,690 kg, with a payload of 1,900 kg.(http://en.wikipedia.org/wiki/Zeppelin_NT http://en.wikipedia.org/wiki/Zeppelin_NT)
redwood 15y ago
Strength is the key part they didn't mention. DARPA probably wants that bit for themselves :) However one must assume this has some strength, otherwise what would the point be. Very cool stuff
- caf 15y ago
  DARPA might well be funding the research for the possibility of a future alternative to FOGBANK in nuclear weapons, which isn't as dangerous to produce.