Every link i’ve seen to this story annoys the hell out of me because they don’t explain HOW the elevator eventually stopped. That’s literally all I want to know.
The best book ever for understanding how Elevators work is a wonderful late 20th century work of fiction called The Intuitionist by Colson Whitehead, which was described by its author as what you would expect to happen if you let a child grow up reading elevator manuals.
There was an elevator hacking talk that went into the buffers at the bottom of the elevator. You may have seen them in elevators that have glass on the outside of the shaft like in malls and hotels. The elevator never rests on those. Those are to take the impact of an elevator that crashes. Inspectors will often test the buffers as well as part of routine maintenance:
The basic theory is that between the car and the wire there is a spring connected to brakes. When the car hangs in the wire this spring is loaded and the brakes disengage, if the wire breaks, the spring returns and brakes engage. All this is mechanical.
What I never understood is how elevators can travel downwards so quickly without such a system engaging. Can they block it somehow or are they never accelerating fast enough down?
Guess again. The cable could break at floor 84, and the elevator car could travel through the next 50 floors, and not slow it’s descent until the 34th floor, at which point, given ten vertical feet per floor, it would still have a total stopping distance of nearly 200 feet, or 2/3 (66%) of a football field.
So, 500 feet of freefall is still substantial. That puts the situation on par with a bungee jump.
Note that it wasn't descending particularly quickly; one cable snapped but other safety systems were still operable.