Luca from Zurich wants to know from Bernie and Lexi:

Why are airplanes always white?

A waving Bernie, in the background a white SWISS aircraft in front of a snow-covered mountain

Bernie: "You paid good attention, Luca! If you take a look round at an airport, almost all of the airplanes are white. Apart from the various logos of the airlines, the airplanes all look pretty similar. This is the case all over the world. However, not because white happens to be everyone's favourite colour 😉. There are other reasons for this. Lexi will reveal the first one to you."

Lexi: "One reason why all airplanes, whether they are big or small, are white is the sun. White surfaces absorb less heat from the sun rays - they reflect them, which means the rays bounce off them. Dark colours on the other hand absorb most of the heat and only reflect a small amount of the rays.

You can try this out quite easily yourself. Place one ice cube on a piece of white cardboard and one on a piece of black cardboard. You will see that the ice cube on the piece of black cardboard will melt faster than the one on the white cardboard. An airplane doesn't melt of course, but the sun rays do heat it up. So, it would get very hot much quicker inside a dark airplane."

Lexi shows an airplane with a colourful customised paintwork at Zurich Airport

Bernie: "But not only the sun rays heat the airplane up - inside there are also lots of technical devices that also radiate heat. This is why airplanes have air conditioning to cool the interior temperature down. A dark-coloured airplane would heat up much more quickly so the air conditioning system would have to work much harder.

However, the higher the air conditioning is set, the more fuel the aircraft uses – and that is expensive and bad for the environment. That is the second reason for the airplanes being white."

Lexi: "Hence, airplanes are white so that it doesn't heat up as quickly inside the aircraft. A higher fuel consumption would also make the tickets more expensive and would be harmful for the environment.

In spite of this there are sometimes airplanes that have so-called customised paintwork for special occasions. Then, the aircraft are decorated with bright patterns and look much more colourful. When you take off with SWISS the next time, Luca, you should keep an eye open to see if you can discover a colourful airplane!"