Length between perpendiculars

Don't ask me how I know that.

Length between perpendiculars, LBP, is measured on deck from the fore side of the stem to the after side of the sternpost on which the rudder is hung, and therefore does not include a counter or a canoe stern.

LBP is one of the factors used in the formula for computing the Thames measurement, which is defined below.

So again, not very important for us really.

Like, it, it, it makes some distant difference if you have big overhangs at the back of the boat.

Today, there are three kinds of tonnage which, uh, with which the yachtsman may be concerned.

The one most commonly used in the UK until recently was devised by members of the Royal Thames Yacht Club in the 19th century for handicapping racing yachts and is known as the Thames Measurement.

Only the beam and the LBP, the length between perpendiculars, are used when calculating it.

Don't ask me how I know that.

Length between perpendicular LBP is measured on deck from the foreside of the stem to the after side of the stern post on which the rudder is hung and therefore does not include a counter or a canoe stern.

LBP is one of the factors used in the formula for computing the Thames measurement which is defined below.

So again, not very important for us really like it it makes some distant difference if you have big overhangs at the back of the boat but um thames uh thames measurement would be is like a i think it's a racing measurement isn't it for an early racing measurement for thames barges when they used to race um and they uh would take that into account depending because waterline length would be increased by the boat leaning over so being able to compare between length overall and length between perpendiculars is useful.

But for most people, like, we don't need to know that.

Today, there are three kinds of tonnage with which the yachtsman may be concerned.

The one most commonly used in the UK until recently was devised by members of the Royal Thames Yacht Club in the 19th century for handicapping racing yachts and is known as the Thames Measurement.

Only the beam and the LBP, the length between perpendiculars, are used when calculating it.