One example of a fast-paced situation in the book "On The Bottom: The Raising of the US Navy Submarine S-51" by Edward Ellsberg is when the divers were trying to attach cables to the submarine while it was being tossed by strong currents and high waves. This was a critical and dangerous task that required quick thinking and precise execution. The divers had to work quickly and efficiently to prevent the cables from becoming tangled or caught on debris while also avoiding getting swept away by the currents.