Watching a sailing boat skim across the water is very different from watching a ship set sail out to sea with a full cargo. However, both of these types of vessels have to rely on lead ballast which is used to create a balance and distribution of weight on the boat or the ship.
Sailing
While many people assume the speed of the sailboat is due to the lightweight materials and the streamlined designed, it is also in the perfect balance of the craft. In this case, the lead ballast is used low in the water to offset the forces on the sail. Without the ballast, the sailboat would easily flip over due to the lateral forces on the sail.
At the same time, the addition of the ballast helps to maintain stability and to also help in keeping the boat lower in the water. Without the ballast, the sailboat would ride too high in the water, creating instability that would make maneuverability extremely difficult at higher speeds.
Smaller Boats and Ships
Smaller boats and ships can have the same type of external ballast, or it can be built into the keel and hull. This can be in the form of cast fixtures, or it can be lead ingots, lead blocks or even lead shot in specifically designed containers.
Larger Vessels
For other types of larger ships and vessels, the lead ballast plays the same important role. However, as there is a greater need for stability on these ships, the keel is often made of lead casting. This is often designed specifically for the vessel and may be cast or machined to the desired shape.
For the very large vessels, and also for smaller boats and ships, the cast may be split for easy installation. It is not uncommon on large vessels for this type of keel ballast to weigh up to two hundred thousand pounds.
