Friday, July 26, 2013

That's how Dean does is (maybe)

The fastest guy in our GPS Team Challenge team is Dean. Every time we sail together, he is 3-5 knots faster than I am. Initially, I blamed it on boards and fins, but now, our boards and fins are almost identical, and he is still that much faster. His technique is probably a bit better than mine, but I don't think that explains the big speed difference.

There are more puzzling things about Dean. When going for speed, I am typically using sails bigger than anyone else out there, but his sails are usually two sizes bigger than mine, even though we are the same weight. But he probably struggles less than I do, often sails 100 km or 100 miles on a day, and does not look beaten up at the end of the day. What is his secret?

One thing that is different are our sails. He always sails on full race sails, usually from Maui Sails. I often use non-cambered sails, including wave sails, especially when I'm on a freestyle or freestyle wave board. Recently, my friend Dani gave me a Maui Sails TR7 that he is not using anymore since he switched to KA Koncept and KA Race sails, and yesterday, I got a chance to sail it for the first time. What an eye opener!

I met Dani at Duxbury. Winds were predicted to be NE, dropping from low 20s to mid-teens over the day. This would have been perfect to do some serious distance sailing along the entire bay. Dani helped me rig the TR7 and rigged a Koncept 5.8 for himself (since I outweigh Dani by almost 50%, his sail was actually bigger than mine relative to body weights). Off we went, nicely powered.

I was impressed right away. I have sailed race sails a few times, and own a couple of HSM GPS sails. I typically found race sails difficult to sail unless fully powered. My GPS 6.6, in particular, was very hard to schlog, and the center of effort (COE) moved quite a lot when going from schlogging to planing. The TR7 was very different - the COE was at exactly the same spot, whether I was schlogging or fully powered in gusts. That made putting the harness lines at the right spot a whole lot easier!

The initial sailing was in 22 mph averages, with gusts to 26. On flat water like Duxbury Bay, my 7.0 non-cambered sail would be fully powered in those conditions. But the TR7 is built for top end stability, and I felt very little pressure in the sail. Clearly, the sail can easily take a lot more wind, even with my limited skills. Compared to other sails I am used to, it seems to have a lot more drive and less drag - the wind is converted into forward momentum instead of sideways pressure. No surprise here, that's one thing the sail is made for.

I did not feel fast, but the GPS showed that I reached some pretty good speeds for conditions. I am usually happy if I go a bit faster than the highest gusts - for example, if I get a top speed in knots that is the same as the wind speed in mph (that's about 15% faster). Yesterday, my top speed was 28 knots (32.5 mph) in 26 mph gusts - not bad! That's probably 2 knots faster than I would have been on my other sails.

We did not follow or original plan to go for distance, since the wind came in NNE instead of NE. This limited runs to about 1 mile, instead of the 3 miles possible in NE; and it meant that the chops was a bit worse for speed on the south side of the bridge, since the wind was going against the incoming tide. Furthermore, the wind dropped down to 17 mph after an hour, and I was planing only in the gusts. I switched to my NP V8 8.5, which I always had liked a lot; but compared to the TR7, it felt like a barely controllable, inefficient monster.

So, I finally get why most speed surfers are on full race sails, even in mediocre winds. Sails like the TR7 make it easy to hold a much bigger sail. Despite all the leech flutter, it has enough drive to get me planing at about the same wind speed as a non-cambered sail, but it is actually a lot easier to sail, especially in gusty conditions. What surprised me a bit was how different the sail felt compared to similar-sized GPS sail. In fairness, though, I have to say that I bought the recommended mast for the TR7 (a Maui Sails SDM, 75% carbon), while I tried to use a mast I had for the GPS (a Fiberspar SDM with similar carbon content). With race sails, having a mast with the correct bend curve is extremely important, and part of the difference is probably due to the different mast. You often hear that having a 100% carbon mast also makes a big difference, but one of the Maui Sails pros has tested the TR7s with 55%, 75%, and 100% masts, and found little difference. I choose a 75% mast because it is less costly than the 100% mast, but also because 75% masts are more durable. I really can't imagine that a 100% mast would be a lot better.

Yesterday's NNE wind was more typical for fall winds than for summer winds. The top speed strips on the Cape still have limited accessibility, and issues like congestion with moored boats. But Labor Day is only 5 weeks away, and I can't wait to see what difference the TR7 will make when I go head to head against Dean on perfectly flat water in 30 mph winds.

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