What does it mean when I describe my Genoa as having a 150% LP? For most sailors, the term LP is often used and seldom understood. The LP or Luff Perpendicular is a measurement used to describe the size of a headsail.

The second important part of the equation is a measurement called the J dimension. The J is the distance between where the forstay intersects your deck aft to the front of your mast.

The LP can be calculated with the "J" dimension (distance from tack fitting to front edge of the mast) adn the sail's percentage size (i.e. 95%, 135% or 150%.)

For example if a Catalina 30 (Standard Rig) owner wanted a 130% headsail for a sailboat with a J dimension of 11.54', the LP calculation would look like this:

11.54' x 1.3 (130%) = 15.0'

A note about 3200/4500 Series Performance Genoas:

Because there are so many different local racing associations it is impossible for us to monitor all the measurement formulas. If you are ordering a 3200 or 4500 Series Genoa, be sure to calculate your LP so that the sail is legal for use in your yacht club. Take advantage of the largest sail you can get without incurring a penalty. Your local club measurer can provide this information.