Rig geometry
Genoa LP and overlap calculator
Use verified J and LP measurements in the same unit. Add I for an approximate sail-area estimate.
Worked example
Example: 120% furling genoa
With J of 4.20 m and LP of 5.04 m, overlap is 120%. With I of 14.0 m, approximate area is 35.3 m² before design refinements.

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