AHVPP - Velocity Prediction Program
AHVPP/1 is a tool for predicting the performance of sailboats. In essence, it is a mathematical model of a sailing yacht. The program takes a yacht's hull offsets along with several other measurements, reduces them to a set of characteristic curves which are then used in formulas giving the surge and moments on the hull and sails as functions of boat speed, course angle, etc. When solving a particular case, the program adjusts boat speed, heel angle, sail trim, sail reefing, and (when doing an optimum downwind or upwind case) heading angle to obtain the equilibrium of all surge forces and rolling moments and simultaneous optimization of sail settings.
AHVPP/1 can be a powerful aid in the design process of new boats as well as in fine tuning boats that already exist.
AHVPP/1 is a generalized VPP, not designed to any "measurement rule". Specifically, it does not give IMS ratings and thus is not intended to replace the specialized USYRU IMS Velocity Prediction Program. Instead, AHVPP/1 includes numerous advantages over the USYRU program. AHVPP/1:
- combines an LPP (lines processing program) and a VPP in a single program
- handles more diverse types of rigs
- allows user input of true wind speeds and headings to solve for
- has greater reliability in finding solutions to different cases
- uses a race model to compare the performance of two yachts in a variety of conditions
- calculates speed predictions for sailing, motorsailing, and powering
- makes input easy with screen-based forms
- delivers screen and printer output of polar diagrams
- comes with personalized technical support