Flying Hamburgers at Sydney Airport

Greetings from Mcdonald's Restaurant at Sydney International Terminal. This is a remarkable sight, the size of a three story house, with a counter on the ground floor, and the kitchen in a translucent yellow glass box above. You order on a touch screen, and this is relayed upstairs, where your meal is prepared, placed in a paper bag, and clipped to a metal belt which lowers it to the counter, where the bag is automatically unclipped and slides down a chute. At least that is what is supposed to happen: I watched as a quarter pounder plunged two floors, after slipping out of the clip. No one was harmed, and the mess was soon cleaned up by the efficient staff. In theory the computer takes care of communications, but in practice staff have to shout up the void with the conveyor in it. An added complication is that the order slips are placed inside the paper bags, so counter staff have to open each, to then shout out the number. A little research by the people at Hamburger University would pay dividends here, I suggest.