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Widowworks

Banned

From: Parma, Ohio

Registered: 2003-09-18

Posts: 1

Re: Helmet Condensation - Science Channel Special

Greetings everyone,
I was lucky to catch the Special that was on the Science Channel a couple of days ago. I found it very interesting. I was thinking about one of the problems the crew was having with condensation inside the helmets, and looked at the windows in my house. A couple pains of glass with some sort of gas between them should solve the condensation problem. Any one have any commnets?
BTW:This is my first post. Welcome me into the fold.
widow

RobertDyck

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From: Winnipeg, Canada

Registered: 2002-08-20

Posts: 7,924

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Re: Helmet Condensation - Science Channel Special

Welcome Widowworks, glad to have you aboard.

NASA currently uses an anti-fogging coating on the inside of the visors. That repels moisture, but as anyone who has tried this with their car windshield knows, it has limits. A double pane with gas between would be a good idea. You could mount two polycarbonate visors in a sealed frame so if one visor broke, the other would continue to hold pressure. You could use a helmet mounted on the astronaut's head like a motorcycle helmet or Gemini helmet instead of the shoulder mount used by Apollo or the current EMU used by Shuttle. That would permit a soft membrane inner pressure layer in case the outer pressure layer cracked. The visor frame would permit either visor to work with either helmet layer to hold pressure. This would provide multiple redundancy with a light weight helmet. A head mounted helmet could act as a crash helmet for astronauts tooling around Mars on an unpressurized ATV-style rover.

Great idea; down-to-earth solution for a space application.

clark

Member

Registered: 2001-09-20

Posts: 6,374

Re: Helmet Condensation - Science Channel Special

Sounds like a good idea, but I think they may be concerned with the problem of "itching the nose". Imagine an itch on the end of your nose, and being utterly unable to do anything about it! Space madness indeed. 

Welcome aboard.

Adrian

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From: London, United Kingdom

Registered: 2001-09-04

Posts: 642

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Re: Helmet Condensation - Science Channel Special

At the MDRS we had real problems with helmet condensation. Not much we could do about it really - I suppose some kind of heated visor and air circulation system might work though.

As for itchy noses, we just had to live with it 

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sethmckiness

Banned

From: Iowa

Registered: 2002-09-20

Posts: 230

Re: Helmet Condensation - Science Channel Special

A couple pains of glass with some sort of gas between them should solve the condensation problem

This helps reduce condensation to a point..  Because it allows for an insulation barrier.  You have the outer glass the inner gas that would ideally be something like nitrogen, but is some sort of dry mixture, then an innner layer of glass.  This has not been used in such temperature extremes. plus, if the outer glass leaks then in condensates.. I think a suit ventilation system would work better.

Being in the military, I have spent some time wearing a gas mask.  Gas masks have to deal with condensation on the inside.  How they do that is when you inhale it pulls air through the canister. the air is then directed across the surface of the plastic as you breath it in.  there is a piece of plastic the covers it and has a slot on the side of it.  The Air force gas mask has a large clear plastic piece that you can see out of.  It works very well, I get sweaty as hell, and sometimes actually get a puddle going in my mask but no condensation build up becuase the air is deflected across the plastic I see out of.  So, something very simple, like that, may work.  If we keep it simple, like that, it would save cost..

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We are only limited by our Will and our Imagination.

Enyo

Member

From: Pacific Northwest

Registered: 2003-10-21

Posts: 36

Re: Helmet Condensation - Science Channel Special

The Apollo and current EMU use airflow over the head and down past the face of the helmet user. I think using the chemical film that divers apply to there helmets and this method should be used.  It would be hard to develop a double hemispheric helmet with some noble gas inside...