Naked Science Forum

General Science => General Science => Topic started by: neilep on 18/07/2007 21:00:34

Title: Why Ice Crystals On One window and Not On the Other ?
Post by: neilep on 18/07/2007 21:00:34

Hi Peeps, I'm Neil.

nice to meet ewe !

This is an airplane window:
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.lifehacker.com%2Fsoftware%2Fuploaded%2F2006-02-22%2Fday-window.jpg&hash=5e858a4c02be9bb0ac875838a777ed86)

it's nice isn't it ?..notice how clean and non icy it is ?

Well, I just came back off a planemobile and this window was all ice crystalled up  on the outside(sorry...don't know the exact scientific terminology for an iced up airplanemobile window)...

....but my window, directly next to it, was not...it was clean and non icy like the one in the piccy..

First Class hugs and shmishes for you kind answers.....

why is this ?......

I noticed other windows also displayed ice crystal  luff and joy!!.................they were in the minority !!

Me wants to know the reason why cos me wants to know the reason why !!

Title: Why Ice Crystals On One window and Not On the Other ?
Post by: Soul Surfer on 19/07/2007 00:13:32

It's bloody cold up there and like houses plane windows are double glazed.  Now they try to keep the air between the glazing sheets dry but I don't reckon they manage to do that for long when the outside gets so cold. so after some time the windows tend to show a few ice crystals on the inside of the outside pane when they get cold.  You may have been lucky or unlucky and got a new one that was replaced becasue something had gone wrong with it and it was pretty good and dry and just didn't get any ice crystals in it at altitude.

Lucky cos you got a nice new window and it had been replaced recently

unlucky the old one had gone wrong and so may go wrong again or the job may not have been done properly anf you might have vanished off into the wide blue yonder when the window popped out!

Title: Why Ice Crystals On One window and Not On the Other ?
Post by: kdlynn on 19/07/2007 00:54:16

ah!!

Title: Why Ice Crystals On One window and Not On the Other ?
Post by: neilep on 19/07/2007 02:00:40

Quote from: Soul Surfer on 19/07/2007 00:13:32

It's bloody cold up there and like houses plane windows are double glazed.  Now they try to keep the air between the glazing sheets dry but I don't reckon they manage to do that for long when the outside gets so cold. so after some time the windows tend to show a few ice crystals on the inside of the outside pane when they get cold.  You may have been lucky or unlucky and got a new one that was replaced becasue something had gone wrong with it and it was pretty good and dry and just didn't get any ice crystals in it at altitude.

Lucky cos you got a nice new window and it had been replaced recently

unlucky the old one had gone wrong and so may go wrong again or the job may not have been done properly anf you might have vanished off into the wide blue yonder when the window popped out!

THANK YOU very much Ian for your kind answer.

Is it because of growing imperfections caused by friction of what ?..dust ?..stuff ?....

I began to think that it may have been something to do with the aerodynamics !..I did not think that they were on the inside of the outside pane..very interesting..THANK YOU again.

Title: Why Ice Crystals On One window and Not On the Other ?
Post by: daveshorts on 19/07/2007 11:03:15

I would have thought it would be the seals in the double glazing unit failing after a long period of heating up and cooling down between =50°C and +40°C and so expanding and contracting.

Title: Why Ice Crystals On One window and Not On the Other ?
Post by: neilep on 19/07/2007 11:05:38

Quote from: daveshorts on 19/07/2007 11:03:15

I would have thought it would be the seals in the double glazing unit failing after a long period of heating up and cooling down between =50°C and +40°C and so expanding and contracting.

Cripes !!..that sounds serious !!