Sinking Condition 

A ship that is reduced to 0 or fewer hit points gains the sinking condition. A sinking ship cannot move or attack, and it sinks completely 10 rounds after it gains the sinking condition. Each additional hit on a sinking ship that deals more than 25 points of damage reduces the remaining time for it to sink by 1 round.

A ship that sinks completely drops to the bottom of the body of water and is considered destroyed. A destroyed ship cannot be repaired—it is so significantly damaged it cannot even be used for scrap material.

Magic (such as make whole) can repair a sinking ship if the ship’s hit points are raised above 0, at which point the ship loses the sinking condition. Generally, non-magical repairs take too long to save a ship from sinking once it begins to go down.