Plasma window vacuum airship?

[fredinno]

3 hours ago, AngelLestat said:

Helium increase the cost, due its high cost and its drawbacks.

And non-flammable materials don't?

3 hours ago, AngelLestat said:

it can not spread and never will blow up,

It may not spread, but it can still explode, and cause serious damage to the airship, cutting more holes, and causing a chain reaction.

 

[AngelLestat]

12 hours ago, fredinno said:

And non-flammable materials don't?

I already explain this several times.. scale..  

12 hours ago, fredinno said:

It may not spread, but it can still explode, and cause serious damage to the airship, cutting more holes, and causing a chain reaction.

How?  hydrogen rise at 20m/s
http://www.arhab.org/pdfs/h2_safety_fsheet.pdf

And you have the wind factor also to spread away of the envelope any concentration.
So there is no way to have a big amount of oxygen mixture enough to ignite and produce a shockwave strong enough to damage the envelope.

The only thing you need to be concern, is to measure the hydrogen purity inside your airship, if it overseed the 1%, you would need to start a hydrogen purification.
But if you manage to always had more pressure inside than the outside, oxygen never will enter.
 

[fredinno]

1 hour ago, AngelLestat said:

I already explain this several times.. scale..  

How?  hydrogen rise at 20m/s
http://www.arhab.org/pdfs/h2_safety_fsheet.pdf

And you have the wind factor also to spread away of the envelope any concentration.
So there is no way to have a big amount of oxygen mixture enough to ignite and produce a shockwave strong enough to damage the envelope.

The only thing you need to be concern, is to measure the hydrogen purity inside your airship, if it overseed the 1%, you would need to start a hydrogen purification.
But if you manage to always had more pressure inside than the outside, oxygen never will enter.
 

If the hydrogen coming out of the airship mixes and explodes, that can cause a chain reaction.

[AngelLestat]

How it will cause a chain reaction?   Explain part by part using mixtures and amounts.
If you dont have a mixture, you dont have explosion, neither ignition.
Remember that hydrogen rise at 20m/s and you have the wind parameter too, so you dont get a huge hydrogen oxygen volume mix waiting to explode.

Edited April 6, 2016 by AngelLestat

[shynung]

@fredinno, I have to agree on AngelLestat on this one.

Yes, hydrogen airships are flammable. Yes, they can be dangerous if built poorly. Yes, Hindenburg will happen again if precautions aren't taken during flight.

But hydrogen airships aren't exactly large floating fuel-air-bombs. They're quite durable, for a few reasons:

-Inside the airship's envelope, the gas is kept at barely above local atmospheric pressure. When the vessel climbs, the envelope inflate to compensate. This means if there are any leaks (say, some bloke aimed a machine gun at it), leaks would happen slowly and, due to the enormous volume of the envelope (and their pressurized hydrogen stores) , pressure would go down slowly as well. If the leaking gas caught fire, given a fireproof envelope, it would not bring down the ship, since the slight overpressure ensures that outside air do not get into the envelope. It's still an emergency, since the vessel is on fire, but most likely survivable.

-The gas inside the balloon is pure hydrogen. This, on it's own, will not burn; it has to be mixed in with outside air to be able to burn. Even if an explosive charge is set off inside the envelope, all it would do is send a pressure wave spike inside the envelope, popping off safety valves and/or overpressure patches (sections of the envelope designed to fail if pressure exceeds a safe limit). Once on the ground, these are easily repaired and patched over, and the airship is good to go.

-The airship envelope is a soft material that won't set off on-contact explosives. Explosive ammunition like this won't be set off on impact, simply punching holes in the fabric smoothly and go unmolested all the way to the outer side, unless it hits something solid inside. Even if it does hit something, pure hydrogen gas do not burn.

To bring down an airship quickly, one would need a warhead that can cut through large swaths of fabric, like this:

This would immediately drop the internal pressure of the airship, while also letting a lot of hydrogen mix with the air. At this state, the hydrogen airship can be blown up with ease.

Edited April 7, 2016 by shynung