The MultiRule project, supported by the Offshore Multihull Association and the Sailing Yacht Research Foundation (SYRF) was the official rating and scoring system for the offshore multihull classes at the 2017 St. Thomas International Regatta, BVI Spring Regatta, New York Yacht Club Annual Regatta, and New York Yacht Club Race Week. The MultiRule project sought to improve both the methodology of predicting multihull performance but also the process through which these performance predictions (polars) were translated into a scoring engine.The project supported a development of a set of tools (velocity prediction program and data analysis), developed in partnership with KND Sailing Performance and Scopic Software, that allows for any yacht in the fleet to generate initial VPP- polars, track its performance and validate and modify its initial VPP-polars through an evolutionary data-collection and analysis process using on-the-water race data.
The Data-polars have allowed KND Sailing Performance to adjust its VPP to produce polar files that are closer to each boat’s observed performance. The standard deviation of the VPP-Polar is 10-15% while the Data-polar is only 5-10% with the data currently logged. As a comparison, the standard deviation for one of the top foiling IMOCAs on the last Vendee Globe is 6.6%.