Boaters know the subtleties required to safely set an anchor, starting with the rule of thumb that you use at least three times as much chain as is needed to reach the bottom.
On ships, the anchors and chains are much larger and the anchorage is much deeper, which can compound a mistake in a hurry.
Here’s a clip we found of a ship deploying an anchor. The procedure begins by the book, but quickly gets out of control.
Judging from the smoke, and then the flames, we assume that the weight of the anchor and chain and the momentum of deployment burned out the brake.
It was a dangerous situation. Apparently no one was hurt, but this type of accident is more common than you might think.
The commercial shipping insurer Gard estimates that one anchor is lost for every 100 ships each year.