## Why Are Most Airplanes Painted White?

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As Aircraft Nerds, we have the craze of looking at aircrafts. We like to observe each and every part of an aircraft and know more about an aircraft. While looking at an aircraft, have you ever wonder why  most of them are painted white?

There are both scientific as well as economic reasons for painting an aircraft white. We will take a look at all of them one by one.

### Scientific Reasons

Before we begin, here is an interesting question about colors

Suppose, there is a yellow colored flower. Then what are the colors (wavelengths of light) absorbed by that flower?

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Most of you will say yellow! But That's wrong!

Yellow colored flowers will absorb all the colors (All the wavelengths of light) except yellow. As that flower cannot absorb the color yellow, it reflects it. That's why we see that flower as yellow!

Now moving towards the color white. Objects painted white cannot absorb any color (any wavelength of light) and so they reflect all the colors (All the wavelengths of light) and we see that color as white. White is actually a mixture of all the colors.

(White color is mixture of all colors)

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When Aircraft is painted with any other color apart from white, it will absorb the light (wavelength) of that color & convert the absorbed light energy into heat energy. This will heat up the aircraft's body.

So when the aircraft is painted white, It will reflect all of the wavelengths of the light and hence will not absorb any light and that will result in it not heating up as much.

Also the color white helps an aircraft to cool down faster when aircraft is parked on the hot ground.

#### 2. Visibility Factor

When an aircraft crashes, most of the time it becomes easier to spot it if its white in color. As white  is easy to spot on the ground from the sky even during the night.

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#### 3. Inspection of Aircraft Body

It is easy to find dents or cracks on white color than on any other color. Hence aircraft maintenance engineers can easily find out defects on an aircraft's body. Also, no color is lighter than white, that is, all colors are darker than white. So if there is any leakage in fuel, it forms a stain on the aircraft's body, and can be detected from the location of the stain. Also if there is corrosion occurring on any part of the aircraft's body it can be easily detected by a visual inspection.

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#### 4. White Color Doesn't Fade

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Any other color fades out when exposed to UV rays (Ultra Violet rays) present in sunlight. As UV rays are capable of breaking down bonds present in the paint which absorbs a specific wavelength of color. As mentioned before, white color doesn't absorb any wavelength of color. Hence, white color isn't affected as much by UV rays. While white color gets dull, it still looks better than any color that has faded out!

So in the case of a white colored aircraft recoloring is not needed.

#### 5. Logo Can Be Seen Easily On White

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Again, all colors are darker than white. Any dark color can be seen easily against white. Hence it's easy to identify company name and logo printed on an aircraft.

### Economic Reasons

#### 1. Painting is Expensive

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Of course, painting the entire aircraft requires an investment of money as well as time. It takes between two to seven days to paint entire aircrafts like the Boeing and the Airbus. Approx 3,600 liters of paint is required to paint the world's largest passenger aircraft, the Airbus A380. In a case of Boeing 747, the simple white polished paint will weigh approx. 25 Kg while if fully painted with any other color over white, the total color will weigh up to 250 kg. Of course, 250 kg of paint will cost more than 25 kg of paint. Also as the weight of the aircraft increases, the amount of fuel required will increase. So the cost of the required fuel will also increase. In addition efficiency of the aircraft decreases with increased weight.

#### 2. Lease Terms & Condition

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Many airlines don't own some of their aircraft. Aircrafts are very expensive. Hence most of the companies take aircrafts on lease. About 56 aircraft are leased by Lufthansa airline. Some leasing companies don't allow painting the aircraft. Hence it is sometimes mandatory for the airline to use white colored palnes.

#### 3. Low Resale Value

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If the owner wants to sell his/her aircraft then painting of the entire aircraft is not needed. Just changing the company name and logo is enough. It saves the owner's money while selling the aircraft. Also if the buyer wants to paint the aircraft with any other color, it is easy to apply paint on white color than on any other color.

So these are some of the reasons for most of the aircrafts being white.

But still some companies use colored aircraft like KLM airline

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