Plastic SpinnakersPlastic Fantastic, low stretch more powerTue, 26th Jul 2011By Chuck Skewes  Recently Ullman Sails got a unique chance to test offshore spinnakers styles in the recent Transpac race. Alchemy the Andrews 70 had a new “Plastic” A4 Spinnaker. Made from Dimension Polyant CZ material, designed for 21-30 knots of wind. This new spinnaker was designed to induce surfing and to allow the boat to punch through the back side of waves more efficiently. Late in the race Alchemy was joined by another 70’ with 600 miles to go. The two boats were 1.5 miles apart with wind conditions 14-18 knots and both boats were in the middle of the A2 range. The sailing between the two boats remained even for 500 miles until the wind reached 22 knots. Alchemy put up their “Plastic” A4 and in the next 8 hours put 7.5 miles on the other 70. It was clearly a knot faster on average. The sheet loads were distinctly heavier. The trimmers had to add a wrap on the winch drums and the grinders could no longer use first gear. Compared to the A2 in the same wind, the loads transferred to the boat were double. This allowed the boat to make it through the back side of waves and to start surfing earlier. Since the sail has virtually no stretch it did not act like a shock absorber when puffs came on. You can feel the difference in the boat and it all translated to speed. This article was posted on Tue, 26th Jul 2011 |
