What is beam on a boat

BOA is the standard term that is used to refer to the widest point of the boat. BOC is used for vessels with multihulls such as catamarans and trimarans.

The bow of the boat is its front end, and the stern is its rear end. The starboard is the right side of the boat, and the port is its left side. The term originally came from wooden ship designs from the distant past. Large timbers were used in the early days to provide strength to the ships made of wood. These timbers sit on top of every rib.

They extend up from the keel and span the whole width of the boat or ship. There is a deck on top of the ship. This deck is made of smaller wooden boards. It acted as a ceiling for the cabins at the first level of the ship. What is beam width on a boat? You need to know how to measure the boat beam width because it will show you if you can safely pass an object on the water or not. When you know what is a boat beam, it will help you in situations on the water.

Measuring the beam involves two steps, namely measuring the centerline and then measuring the beam. You can also measure the beam at certain specific points on the hull, such as the cargo area or the pilothouse. However, you should designate the names of the structures where you got the measurement.

Naval architects use the beam, along with the length and draft, to design a boat or ship hull for a certain purpose or job using the principle of deadrise. These three measurements, namely length, beam, and draft, together with deadrise, are the factors that determine the shape and handling characteristics of the hull of a boat or a ship. This is the formula that can be used for monohull watercraft :. It is also crucial in determining its stability. However, that goes beyond the scope of this article.

A boat that has a wider beam enjoys higher initial stability. The stability of the boat beam is also affected if its volume is shifted away from its centerline. Stability will be reduced if most of the volume is near the centerline. This is where a wider beam is more advantageous. A boat with a wider beam will enable its volume to be shifted farther away from the center, making it more stable than a narrow-beamed boat.

A wide-beamed boat has issues with secondary stability. This is the quality of a vessel when it accidentally tips on its side. While a wide-beamed boat can be tough to tip on its side, it will capsize very easily once it does. However, secondary stability also depends on the bottom shape of the vessel. A boat with a curved bottom has a higher secondary ability than a boat with a square bottom. A narrow beam on a boat makes a boat less stable. However, they are generally faster than wider-beamed boats.

Boats with narrow beams are also less sluggish and are safer and easier to maneuver around obstacles. Boatbuilding and shipbuilding are very different today than they were many decades ago. These steel beams are called torsion boxes. The width of one such box can be as wide as twenty people stretched across the hull. Stronger and more durable options are now used.

Some of these options include steel, iron, composite material, and Ferro-cement. In designing boats, boat architects use the length to beam ratios to determine how wide the beam of a boat should be. For small boats such as trailerable boats and dinghies that are not more than 20 feet long 6 meters , they use the ratio of That means the beam of a boat should be one-half of its length. For more than 30 ft. That means the beam of a boat this size should be one-fifth of its length. In the beginning most people have difficulty remembering which is Port and Starboard and this can cause embarrassing navigational mistakes.

There are a number of way we can remember which is port and starboard. Ahead and Astern are used to describe direction. Catamaran and multihull vessels have more than one distinct hull and therefore have more than one BOW and STERN and may require further discrimination. The BEAM of a vessel is traditionally where the largest deck beam extended across the widest point of the ship from one side of the hull to the other.

In speedboats the beamiest point is usually near the stern. Basically the wreck would be located halfway between the bow and the beam on the port side in the area of the port bow. When giving a position from the boat, you can identify it by reference to parts of the boat, like Bow, Beam, Quarter, Astern and whether it is on the Port or Starboard side. You could also identify the position by giving the relative angle in degrees from the bow.