Comments on: Gasless DIRIGIBLE for Safe Air Travel

By: KHarn

KHarn — Fri, 16 May 2008 23:32:56 +0000

Benzene,
Take a look at THESE big boys:
http://www.airships.net/

By: Mike

Mike — Tue, 13 May 2008 04:02:34 +0000

Local radio network, emergency broadcasting, border patrol, solar power collection, airborne experiments station.

By: Benzene

Benzene — Mon, 12 May 2008 15:43:53 +0000

How about a hybrid? Part helium, part vacuum in magical carbon nanofiber shell. >.>

But, is a super airship marketable outside of the ad industry? I can see the advantages in vertical takeoffs and lower fuel consumption, but they’d have to be mighty fast to compete with modern planes and even helicopters. Also, there’s that whole thing where most of the volume is filled with helium or nothing and can’t be used to store cargo, passengers, etc. That might look bad to potential investors. Super airships might be perfect for international travel, but they’ll probably get stuck filming football games and carting local tourists around like their helium-filled ancestors.

By: JMyint

JMyint — Mon, 12 May 2008 13:45:44 +0000

I know of no material that weighs less than 1.2 grams per litre that has the structural strength to resist one atmospher of pressure.

By: Richard Conto

Richard Conto — Mon, 12 May 2008 12:55:20 +0000

What about more modern materials – aren’t there some ceramics or foams that could do this? And the gross shape wouldn’t need to be limited to a sphere or – whatever the shape of a blimp is –

By: Torgo

Torgo — Mon, 12 May 2008 03:01:21 +0000

This is interesting, because this is very similar to an idea from the middle-ages – of traveling to the Moon using vacuum filled copper spheres.

By: JMyint

JMyint — Mon, 12 May 2008 00:23:26 +0000

Uhm…No. A sphere with a vacuum will not float. The object would have displace a weight in air equal to its mass. As the object is scaled up the walls would have to be thicker and the internal bracing greater to resist the air pressure. A litre of air weighs in at about 1.2 grams so at 1 cubic metre this object would have to weigh in at 1kg or less. Helium weighs about .17 grams per litre and hydrogen at .09 grams per litre so they displace a sufficient amount of air to provide lift and they press back against the air aiding structure.

By: Rick Auricchio

Rick Auricchio — Sun, 11 May 2008 18:10:26 +0000

I think the author assumes the cylindrical shape would withstand atmospheric compression. I believe the opposite is true. With internal pressure, we get a nice spherical shell. With exterior pressure, the walls would collapse where there was no support.

By: Neil Russell

Neil Russell — Sun, 11 May 2008 15:33:41 +0000

Funny how the author poo-poos helium because it was in such short supply, but beryllium just needs a simple metallurgical miracle and presto! Lightweight airships. No problem