Why Do Ships Sink: Angle Of Loll Explained

We use Lol daily to express humour or fun when reacting to a fun textual conversation. However, there is no fun when the ship reacts to the “angle of Loll.”

The angle of loll is a term used in the shipping industry to describe the dangerous situation that can occur when a ship has a permanent inclination or heel to one side, even when it is at rest and in calm waters.

It is the angle at which a ship with a negative initial metacentric height will lie at rest in still water with a particular angle of heel.

The ship will oscillate about this angle of the heel. In case of further imbalance in the weight distribution within the ship or loss of buoyancy, the ship may also tend to capsize, which is why this is a very dangerous situation onboard and must be corrected.

The angle of loll can occur for several reasons.

One of the most common is a shift in the weight distribution of the ship. This can happen when cargo is loaded or unloaded unevenly or when ballast water is not distributed properly.

Another cause can be the loss of buoyancy on one side of the ship, such as from a leak or damage to the hull. This can cause the ship to lean to one side, creating a dangerous situation.

An angle of loll can be corrected only by lowering the centre of gravity, not by moving loads transversely.

This can be done by moving weight downwards, adding water ballast in double-bottom tanks or removing weight above the ship’s vertical centre of gravity.

Where empty ballast tanks are available, these will afford the simplest means of lowering the ship’s centre of gravity. All slack tanks can be pressed up.

The correct procedure is to add ballast on the low side of the ship. The first effect will be to increase the angle of the heel and to cause a loss of stability due to the free surface of the water, but this effect is soon cancelled, and the angle of heel will rapidly decrease.

In any case, it’s important to correct the angle of loll as soon as possible to ensure the ship’s and crew’s safety.

Have you ever encountered an angle of loll onboard your ship, or what was the highest list angle you faced on ships? Let us know in the comments below!

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