How are large ships launched into water?

Have you ever wondered how those massive cruise ships and cargo vessels are launched into the water? The process may be more complex than you think.

There are two main techniques used to launch large ships: the traditional side-launch method and the more modern dry-dock method.

The Side-Launch Method

The side-launch method involves sliding the ship sideways into the water. Historically, this method was used for small ships, but as ships grew in size, so did the need for larger launch facilities. Today, the side-launch method is primarily used for naval ships and vessels built in dry docks with a sloping launch ramp.

The process starts by constructing the ship on launch blocks or keel blocks on a sloping launch ramp. As the construction progresses, temporary supports are added to stabilize the ship. After completing all construction work, the temporary supports are removed, and the weight of the vessel is supported by the launch blocks.

The final step is to apply a thick coat of grease on the ways, or the launch ramp, and underneath the ship. This helps reduce friction and allows the ship to slide smoothly into the water. The ship is then released from the launch blocks and slowly eased down the ways into the water.

Dry-Dock Method

The newer, more modern method of launching large ships is the dry-dock method. The ship is constructed inside a dry dock, which is then flooded with water to float the vessel out for the first time. This technique is used for larger ships that cannot be launched through the side-launch method.

The dry-dock method starts by building the ship inside a large enclosed dock, which is typically made of concrete. Once the ship’s construction is complete, the dry dock is filled with water or floated beside a body of water. The supports holding the ship are then lowered and removed so that the weight of the vessel is supported by the water.

As the water level rises, the ship floats off the supports and exits the dock. The ship can then be towed to its final destination, where it undergoes final outfitting and finishing work.

Whether it’s through the traditional side-launch method or the more modern dry-dock method, launching a large ship requires extensive planning and coordination. It’s truly a remarkable sight to see, watching a giant vessel slide into the water or float off its supports for the first time. Nevertheless, the launch is just the beginning of a long, complicated process that requires many skilled workers and specialized machinery to get a vessel smoothly sailing the seas.

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