Length Between Perpendiculars (LBP) Created OnFebruary 8, 2018byCult of Sea Print You are here: Glossary L Length Between Perpendiculars (LBP) < Back to Glossary IndexThe length of the vessel measured between the forward part of the stem to the after part of the rudder post. Related:KeelHog (Hogging)Rudder postArrived shipCancelling date or LaycanLength Overall