Why different color codes for underwater ordinance?

Was reading a guide to color codes used for bombs, missiles and such, and several colors had a little footnote saying they were meaningless on underwater munitions (mines, torpedoes, etc.).

Since these color codes seem to be shared by both land and sea-based aircraft (and presumably ships and land vehicles too), I’m wondering why the underwater stuff is different.

Here’s my source: http://navyaviation.tpub.com/14014/css/14014_182.htm

The Council of Atlantis, deep below the sea, enacts whatever ordinances they wish for their isolated society.
They can color-code their munitions, or ordnance however they wish. :slight_smile:

(Note: I once had occasion to note this same spelling correction on an academic research paper I was proof-reading.)

I think it says that the color scheme doesn’t apply to underwater ordnance, not that there is a different color system. In other words, mines can be any color. I would think this is to make mines less visually detectable; they could be camoflauged in any way that seems appropriate.

Also, a lot of the fillings listed in the chart wouldn’t be used in mines or torpedoes, so color coding is irrelevant.

I believe color perception changes with the depth of water.
One certainly would not want to make a mistake in identifying such devices.

Yeah, water filters out different wavelengths of light more or less efficiently so apparent color can shift quite a bit at various depths.

If I recall from my dviing classes way back when, red really only penetrates something like 20 feet while the blue end goes much deeper.

So anything that is being seen with surface illumination (as opposed to total darkness except for a local light source) is going to shift.

Oh, and that’s just in terms of light penetration. Then there is also the matter of water turbulence and suspended matter that can scatter the light and also mess with color.

The climax of the movie The Abyss comes to mind…

(Ed Harris’ character, deep underwater in a diving suit, has to disarm a nuclear warhead. There are two wires, one is yellow-and-blue striped, the other is white-and-black striped. His helmet is filled with pink fluid, and his only light source is a green flare. Good luck picking the right wire!)