Forces on sails (3 m) = 5-m/s (≈10-knot) wind at 3 m above the water would be approximately "V" (15 m) = 6 m/s (≈12 knots) at 15 m above the water. In hurricane-force winds with "V" (3 m) = 40-m/s (≈78 knots) the speed at 15 m would be "V" (15 m) = 49 m/s (≈95 knots) with "p" = 0.128. This suggests that sails that reach higher above the surface can be subject to stronger wind forces that move the centre of effort ("CE" ) higher above the surface and increase the heeling moment. Additionally, apparent wind direction moves aft with
North Sails to designing sails, with the goal of building sails that were faster than the competition’s. North began testing the strength and stretch characteristics of sailcloth he received from his suppliers, to eliminate variability in his raw materials. He introduced computer-driven cloth cutting machines, to increase the consistency and repeatability of a sail design. North was a pioneer in computer modelling of sail forces and structural loads. North used a laminated Mylar and Dacron sail on the 12-metre "Enterprise" in 1977. North’s emphasis on computer technologies and new materials is reflected in the company today, which makes intensive use of computer