ask and yo shall receive
His answers will be posted here. This is a rare opportunity to ask one of the greats in sailing something you have been dying to know. Everybody has something to ask, so do it here. And do it now.
Q: Why do some keelboat sailors hang their mast over the bows so far that they seem to be losing projected area. I have asked loads of good sailors, including pros, and have never received a convincing or comprehendible answer. Either waffle about downward vectors, or it’s just fast” I can’t be the one who too stupid to work it out!
A: The answer is quite simple. It’s to avoid the “barn door” effect. You need to have flow across the sails. If the sails are simply square to the wind there is no flow and it’s slow. By leaning your mast as far forward as you can, you get flow from the bottom of the sails off the top and this improves boat speed. It also moves the center of effort forward and allows you to sail in a straight line with no weather helm.
Q: I have done Bermuda twice, Marblehead to Halifax twice, and will be doing a leg of the clipper race in 2015. Other than that what is your advice to a sailor who wants to do more serious ocean racing? i.e. Transatlantic, Fastnet or Sydney to Hobart. How does one make the next step?
A: You need to decide which projects or races you want to do and target the boat(s) you want to sail on. Choose the best boats because you always want to be the lowest member on a top boat rather than the top guy on a slow boat. This is how you learn and get better. Offer to do anything on the boat just to get a foot in the door. Wash the boat, pack the sandwiches, whatever it takes. If the boat needs to be delivered back after a race, offer to crew. Get your foot in the door and once you are recognized as hard working and a good sailor you will get plenty of opportunities to sail on some top racing boats. Soon you will be able to pick your races and pick your rides. Always try to get on a boat that has more experienced sailors that yourself so you can learn.
Q: I do the tactics on a J/111 and I am constantly getting into arguments about TWD vs. relative angle (heading) to the windward or leeward mark, i.e. if the windward mark is at 35deg and I’m tacking through 70 deg, then my heading on starboard would be 0 deg; and my heading on port would be 70 deg, assuming the wind direction is at 35 deg. One of the crew members looks only at TWD as an indicator of a lift or header and I look at angle (heading) to the mark. I often find that TWD when going up wind is not the most reliable number and in my opinion heading is the most accurate number. For example if the TWD says 42 deg. the crew member will say we are lifted, however I will point out that our heading on port tack is still 0 deg. and it’s an equal split between port or starboard. Please help put this to rest finally. Also assume that velocity and wave pattern are equal on both tacks.
A: If you are racing a J/111 you will have instruments on board. Let’s presume that they are new and calibrated. They need to be calibrated often so that you have full confidence in what you are seeing. If this is the case, you can use TWD as your gauge. If the instruments are not calibrated, or if you are in a dinghy, you will have to use the compass, but TWD is better and more accurate. Bear in mind that there may be as much as 10 degrees of difference in course due to a puff or a lull. When you get a puff you get an artificial lift from the added velocity; same for a lull except it’s the opposite.
When sailing downwind it’s all about boat direction (heading) and the opposite gybe number. A good indicator is to look at your masthead fly. It will be pointing in the direction you will be going after you have gybed. This is particularly useful for gauging laylines.
Q: Hey Dave, assuming a standard 30-45 foot keelboat, is there any situation where carrying the boom above centerline is fast?
A: It’s absolutely faster, especially in light to moderate winds and smooth water. It’s a balance of speed and VMG, but in smooth water you will be able to point higher with the boom above centerline. You will be going a little slower but your VMG toward the windward mark will be better. As soon as there is some chop you need to keep the speed up. You can still have the boom at or slightly above centerline, but don’t concentrate on VMG. Instead go for enough speed to keep the boat moving through the waves. In light winds and smooth water you can have the boom around 4 – 5 degrees above the centerline without hurting speed too much. Remember that it’s just the boom and lower quarter of the sail that is above centerline; the rest of the sail is still below centerline.
October 31st, 2013