Early flight borrowed from nautical knowledge. The assumption that a modified ship's propeller would work in the air turned out to be true. Large planes, and especially airships, were commanded from a veritable bridge, complete with a steering wheel and telegraph. Pilots used nautical sextants to 'shoot' the sun and establish their position. Propellers went through a lot of experimentation before becoming what we see today. As for colors... the First World War squadron leaders had their planes painted in highly individual colors, a tradition born from medieval warfare and jousting tournaments. Flying early planes was considered a gentleman's occupation, and propellers were beloved collectables--often the only part of a plane that was deemed worthy of saving.