Color Perception

COLOR PERCEPTION - by Clay Ramskill [Adapted from an article by Dr. Robert Suding, published in MAA, Russ Roepke, editor, Temple Texas.]

How many times have you seen it? A plane crashes -- not from equipment failure or specific pilot dumb thumbs, but because the pilot couldn't tell what his plane was doing! Often as not, the plane involved was covered in a relatively dark, solid color.

We all know that we must see our aircraft to control them. We must not only see the plane, but know its attitude -- the relative positioning of the plane with respect to the earth. How we cover or paint the plane has a lot to do with our ability to do this, under the various conditions under which we fly.

The Color. The accompanying chart gives relative visibility for various colors, but doesn't note under which conditions it's good for. It should be pretty obvious that the background is important, too. For instance, white is listed as a top contender -- but we know that a white plane can really disappear against a light cloud background. A dark blue plane shows up fine in a clear sky -- but nearly disappears when you drop down in front of the tree line.

The Pattern. Small, intricate patterns may look great, but will essentially disappear at any distance and are of little help as far as flying the plane is concerned. Larger patterns are better here -- but they should somewhat conform to the shape of the plane. Let's face it -- large irregular blobs are regularly used as CAMOUFLAGE for planes and ships. You see something (it's hard to completely hide a large airplane or ship!), but since it doesn't conform to the SHAPE you're looking for, you mind dismisses it!

Shades. The part of your eye that perceives illumination (in black and white) is 2000 times more sensitive than the part that perceives color. As your plane gets farther away, the actual colors get less prominent. But you can still easily see differences in brightness. So CONTRAST becomes very important. This is even more true under poor lighting conditions! At a distance or in poor lighting, the difference between green and blue just doesn't show up, but you WILL see the contrast between a light color and a dark color. Note that as we age, our color perception gets even worse. Bad news for those of us in the Alzheimer's crowd!

Visual clues. As we fly, we need several cues to tell us what the plane's attitude is. Probably most important is it upright or downside up? We need to be able to see the wing's bank angle clearly, especially on landing approach. And it's nice to know whether the nose is up or down! Putting it all Together. The actual colors used are not nearly as important as CONTRAST. Large areas of contrasting colors, conforming to the plane's shape, will show up best in varying conditions. Have contrast between the top and the bottom and along the wing, including the leading edge area. Some type of contrasting color line or stripe along the side is good, also.

Note: Both the Navy and the Air Force use these principles for their training planes, a situation where visibility and safety are paramount. Both services use white, with large contrasting areas of orange or orange-red. 'Nuff said??