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SAIL PLAN DIMENSIONS
Figure out your rig dimensions when it comes to your sails.
The basic rig dimension for a yacht are generally understood. However, there are some differences in how some sailors describe these dimensions. Here is how we define them at North Sails.
I – Height of Foretriangle Elevation of Forestay, measured down to elevation of main shrouds at sheer line.
J – Base of Foretriangle Horizontal distance measured from front face of mast at deck to position of headstay at sheer line.
P – Mainsail Hoist Elevation of upper mast band or maximum main halyard position, measured down to lower mast band or top of boom.
E- Mainsail Foot Horizontal distance measured from aft face of mast at top of boom to boom band or maximum outhaul position.
Is – Height of Inner Foretriangle Elevation of Forestay, measured down to elevation of main shrouds at sheer line.
Js – Base of Inner Foretriangle Horizontal distance measured from front face of mast at deck to position of inner headstay at sheer line.
Py – Mizzen Mainsail Hoist Elevation of upper mast band or maximum main halyard position, measured down to lower mast band or top of boom.
Ey – Mizzen Mainsail Foot Horizontal distance measured from aft face of mizzen mast at top of boom to boom band or maximum outhaul position.
ISP – Elevation of Spinnaker Halyard Measured down to elevation of main shrouds at sheer line.
SPL – Spinnaker Pole Length
STL – Spinnaker Tack Length Horizontal distance measured from front face of mast at deck, forward and horizontally to position of spinnaker tack attachment point.
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19 September
OFF-SEASON AND WINTER SAIL CARE GUIDE
17 September
FOUR KEY COMPONENTS TO OFF-SEASON SAIL CARE
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Rig Dimensions
The following abbreviations are often used to describe various measurements on a sailboat. Precise technical definitions exist for each abbreviation, but the following is a list of simple descriptions.
| LOA | Length Overall - overall tip-to-tip length of the boat |
| LWL | Length Waterline - length of waterline of the boat |
| DWL | Design Waterline -theoretical waterline length of boat as opposed to LWL, which is actual waterline length |
| BMX | Beam Maximum - width of the boat at the widest point |
| BWL | Beam Waterline - widest beam of boat at the waterline |
| I | Height of the foretriangle measured from the top of the highest sheave to the sheerline |
| I2 | Height of staysail halyard above deck |
| J | Base of the foretriangle measured from the front of the mast to the intersection of the forestay and deck |
| J2 | Base of staysail triangle |
| P | Luff length of the mainsail |
| E | Foot length of the mainsail |
| LP | Shortest distance from headstay to the clew of the jib |
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