Back in the 1920s, wingwalking claimed lives. Daredevils would move around on the top of a plane's wings, in mid-flight, often without any harness or any safety line. Maybe they'd be able to clip onto something during takeoff and landing, but maybe not. There are still a few of those true daredevil wingwalkers out there in the world, but in the 21st century... it's usually a bit different.