Portsmouth Formulas

Portsmouth Yardstick Formulas Copyright © 2008 by N. E. Richards and J. F. Spinnler Reprint permission by the authors is required for material in the Portsmouth Yardstick Please contact hobockd@aol.com for permission
Table I	Beaufort Scale of Wind Velocity
Table II	Weight Factors and Beaufort Number
Table III p1	Class Types and Rating Formulas for Centerboards and Multihulls
Table III p2	Class Types and Rating Formulas for Keelboats and Offshore Classes
Table IV	Calculation of PNs and Wind HCs from Rating Formulas and Factors
Table V	Relationship of D-PN to PHRF; convert D-PN to PHRF and vice versa
Table VI	Optional Modification Allowances (Not applicable to Multihulls)
Table VII	Table of Primary and Secondary Yardsticks