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homerthedoomer
08-01-2005, 05:14 AM
This might sound stupid to most of you, but why do submarines switch to red light? And what's the deal with the red goggles the crew in Das Boot is wearing occasionally?

homerthedoomer
08-01-2005, 05:14 AM
This might sound stupid to most of you, but why do submarines switch to red light? And what's the deal with the red goggles the crew in Das Boot is wearing occasionally?

Fish40
08-01-2005, 05:34 AM
The red light was used in low light conditions, to enable the crew's eyes to adjust. For example, if it were night, you would switch to red light, a few minutes befor surfaceing(if you were submerged) to allow your eyes to adjust for the dark. Hope that helps. http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

homerthedoomer
08-01-2005, 06:12 AM
Thanks for the quick reply http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif
So I guess the goggles serve the same purpose...

WhiteKnight77
08-01-2005, 06:17 AM
Yes.

jcurrens
08-01-2005, 07:28 AM
Wasn't this done because of reflection purposes? I thought I read somewhere that it was so the Allies would not see a glint of light while the periscope was sticking out of the water?

Celeon999
08-01-2005, 10:07 AM
Here is an old thread maybe of interest for you.

Red and Blue lights on u-boats (http://forums.ubi.com/eve/forums/a/tpc/f/857101043/m/8521008733/r/8521008733#8521008733)

rudewarrior
08-01-2005, 11:31 AM
The other is that red light is one of the most difficult for us, as humans, to see, especially at night. Since it is harder to see, our eyes will not be as affected by using red light to illuminate then going to nighttime conditions outside the boat. Also, remember a periscope actually works both ways, if you raise the periscope and white light comes out of it, it can be spotted at night. If red light comes out it is much more difficult to spot at low light conditions. Same issue when surfacing at night and opening the top hatch. Light coming out through the top hatch could give away your position.

HimmelJaeger
08-01-2005, 12:04 PM
So as a joke, you could install some Xenon 8000k HID lights in your friend's U-boats?? http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

gunnulf229
08-01-2005, 05:36 PM
I've read quite a few U-Boat books(well, honestly, all sorts of WWII submarine books). From what I recall, it is to help you keep your night vision at it's peak, as even a quick or small exposure to white light can cause your night vision to be affected for a while (something like up to 20 minutes to get re-acclimated as I recall). For those of us who have gone up on the bridge at night with poor visibility and little light, it is easy to imagine how important having adjusted to the light conditions would be prior to going on watch. It could literally mean the difference between life and death. The goggles were worn, so that if you needed to go back into the boat, where lighting might be bright, you would be preserving your night vision, and not have to spend a bunch of time on watch waiting for your eyes to adjust to the dark. I know as I have gotten older, my eyes aren't what they used to be, and it takes quite a while for my eyesight to adjust to truly dark conditions if I've been in even moderate lighting, so I can well believe how this might have been serious stuff for those u-boatmen who were lookking not only for merchants, but keeping a sharp eye out for something with teeth that could mean a quick death for the whole crew.

pcisbest
08-01-2005, 07:02 PM
This is not something that is just peculiar to subs. Haven't you guys looked at a military flashlight and seen teh colored lens? Same thing with military transport aircraft: they will got to a red lighting when it is dark outside.

aaronblood
08-01-2005, 07:19 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by pcisbest:
This is not something that is just peculiar to subs. Haven't you guys looked at a military flashlight and seen teh colored lens? Same thing with military transport aircraft: they will got to a red lighting when it is dark outside. </div></BLOCKQUOTE>

It's commonplace in civilian aircraft as well...

If you ever take a ride in a little Cessna at night, you'll notice the interior controls and panel lighting is red. This way it won't ruin the pilots adjusted night vision when he needs to glance down at a map, etc.

Has to do with the red light not causing the dialated pupil to contract. ...and yes those goggles are meant to help the pupils to dialate before someone goes up on watch.

Fish40
08-02-2005, 03:09 AM
Now that I think about it, my buddy's fishing boat has a dome light in the cabin, not unlike the ones that are in the roofs of cars. The only difference is, there is a toggle switch to change between white, and red light. While fishing on nights where there is no moon, we sometimes keep the red light on in the cabin, just in case we need to go in for something. It offers just enough visibility to allow you accomplish your task, and you don't have that momentary period of "blindness" when you go back out.

WilhelmSchulz.-
08-02-2005, 12:10 PM
Your a former submariner gunnulf??? http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif

Faamecanic
08-02-2005, 01:04 PM
ROOOXAANNE... You dont have to turn on the Red Light... ROOOOXANNE....

ROFL...sorry couldnt resist. I am getting in touch with my inner troll.

"And Now for something completely diffrent"

Faamecanic
08-02-2005, 01:06 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by pcisbest:
This is not something that is just peculiar to subs. Haven't you guys looked at a military flashlight and seen teh colored lens? Same thing with military transport aircraft: they will got to a red lighting when it is dark outside. </div></BLOCKQUOTE>

Also the red light from a military flash light will not travel as far as white (and give away your position).

But mainly its for preserving your night vision.

Johncb1957
08-10-2005, 06:25 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by homerthedoomer:
This might sound stupid to most of you, but why do submarines switch to red light? And what's the deal with the red goggles the crew in Das Boot is wearing occasionally? </div></BLOCKQUOTE>

the red light was used by night and white light by day,,, it was used so the crew could maintain psycological body clock and make a definite distinction between night and day.It is important to understand not all the crew got to be on the bridge, but may of spent many days down below, not all could cope with this,, submariners where specially selected men.Red and white light is still used today on subs.