"Clap Skate"
"As early as 1936, R. Handl was working on a skate with a movable heel plate. However, it took until 1996 before such a system, called 'clap skate', revolutionised the sport of skating.
R. Handl, 23 October 1936"
"Look here and wait for the flash..."
that has been around since at least Nam.
A little turbulence and the kid ends up three seats away. :)