Skywriting or skytyping is usually a staple at any air show, wowing crowds with feats of aerial dexterity and often proposing marriage or reminding the audience to drink soda. Developed by British aviator John C. Savage in 1922, the techniques are created by vaporizing fluid, such as paraffin oil, in the plane’s exhaust system to form letters in the sky. These letters can be as tall as two Empire State Buildings stacked on top of each other.