Why are airplanes washed every 7 days?

The weekly washing of airplanes that takes place is necessary not only for the sake of appearance.

Dirt accumulates on the surface of airplanes, which increases aerodynamic drag.

The accumulated dirt leads to increased fuel consumption during flight: the difference can be up to 2%.

For a large passenger airplane such as a Boeing 777, dirt and fouling buildup can result in additional fuel costs of up to $5,000 per month.

In addition, dirt can hide minor damage and early signs of corrosion, posing a safety hazard.