When I was doing my electrical apprenticeship, I worked on a conveyor system for a new international airport terminal. To say that thing was an engineering marvel would be an understatement. 40 different panels that were the size of a 2 car garage door and 3 feet deep that housed all of the motor starters, relays, terminal blocks, etc. The 270 degrees of bar code scanners with odometers on the conveyor that tell the pinball flipper that's 100' down the line which bag to flip to another line. When you consider the volume of passengers, connecting flights, and how the time it takes you to get from one plane to another and your bags are already there, it's amazing.