Planes that are freshly painted are 'slick' -- they have noticeably less drag! A good paint coating also makes it easier to wash dirt and other contaminants, wh

Planes that are freshly painted are 'slick' -- they have noticeably less drag! A good paint coating also makes it easier to wash dirt and other contaminants, which cause drag and corrosion. Corrosion is indeed a problem, but only severely for salty places. Paints also have UV screen for plastic composite components.