Question re: sailing downwind leg - Page 2 - SailNet Community
Old 05-19-2017
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Re: Question re: sailing downwind leg

Ddw is generally your slowest point of sail. When sailing a course that is dead downwind always sail 20 degrees above ddw. Find a polar plot for the Ranger 26 and you'll see that your velocity made good is greater when you sail 20 degrees above ddw than if you had sailed ddw. Your greater extra speed more than compensates for distance that you will travel.

So how do decide which gybe to sail on? Upwind you sail on the lifted tack; downwind you sail on the headed gybe.

So how do you decide which gybe is headed? When you round the windward mark bear off until you're 20 degrees above ddw. At this point look at your bearing. If it is less than 20 degrees above the rhumb line, you are on the headed gybe. Stay on the headed gybe. If it is more than than 20 degrees above the rhumb line , you are on the lifted gybe. therefore, you should gybe through 40 degrees so that your heading is within 20 degrees of the rhumb line.

Last edited by Hudsonian; 05-19-2017 at 07:41 AM. Reason: Correct mistake
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Re: Question re: sailing downwind leg

Thanks guys!!! you are all awesome and this is turning on light bulbs for me. I still have to process all this and make sure I completely understand all the minutia about which you speak, as a lot of it I don't have a firm grasp of. I'll print out this thread and review it with my team.
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Old 05-19-2017
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Re: Question re: sailing downwind leg

Quote:
Originally Posted by Hudsonian View Post
Ddw is generally your slowest point of sail. When sailing a course that is dead downwind always sail 20 degrees above ddw. Find a polar plot for the Ranger 26 and you'll see that your velocity made good is greater when you sail 20 degrees above ddw than if you had sailed ddw. Your greater extra speed more than compensates for distance that you will travel.
Most polar diagrams assume that a spinnaker will be used. Main and jib polar diagrams may be available for some boats, but where would you find those?

This is an excellent article on subject by an excellent sailor that I raced against a long time ago! Probably covers everything a JAM sailor needs to know about downwind sailing

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Old 05-19-2017
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Re: Question re: sailing downwind leg

Hudsonian is spot on.
What you have to do for 'consistency' is to 'profile and record' which heading down wind and by which method (impact sailing or aerodynamic sailing) works best vs. VMG. For 'consistency' you really need a well developed historical data log of which angle under varying wind strengths and wave heights vs. sail shape vs. which method (drag v. aero) will work best. .... and then practice, practice, practice etc. ... to 'optimize' by building your OWN set of polar diagrams.

Last edited by RichH; 05-19-2017 at 10:43 AM.
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Re: Question re: sailing downwind leg

Thanks again Rich and Free Agent! I just downloaded and printed the article.
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Old 05-19-2017
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Re: Question re: sailing downwind leg

I searched Ranger 26 cursorily. The group on facebook seemed promising.

On one boat that I raced we developed polars for each of the four spinnakers that we carried. It certainly required systematic data collection but we enjoyed big gains sailing to the polars. Technology is making it easier. None-the-less, I doubt many beer can racers are so committed that they'd develop a set of polars.
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Old 05-19-2017
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Re: Question re: sailing downwind leg

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Originally Posted by StarwindMango View Post
This is always a topic of discussion when our crew sails beer can races in non-spin class. What we've found is that taking the shortest course to the mark (read dead downwind) almost always is the better solution than reaching back and forth. Two reasons: 1) Reaching back and forth causes you to jibe a lot, which can be a slowdown if you're having to move the whisker pole. 2) It's almost impossible to have enough boatspeed to catch those who sail the shorter course, and even if you did you're sailing extra distance that the others aren't. I race on one of the fastest boats in the fleet and if reaching across on the downwind leg, we can't catch up to boats that went dead downwind.
This is also my experience. I understand the theory of going the long way and jibing, and understand how it's the obvious choice for semi-planing hulls and well-trained crews and stuff, but when flying white sails with most regular displacement hull boats in regular conditions with regular cobbled-together crews, just going wing and wing DDW is a winner.

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Re: Question re: sailing downwind leg

All the points about wanting to be on starboard tack and (or) not having to gybe around the leeward mark are great, but what matters in a race is getting there first. As you said originally, the boats on the other gybe were gaining on you. In a race you need to do what's fastest. Starboard tack isn't going to help you if you can't keep up with the guy who's on port. Not having to gybe at the leeward mark isn't going to help you if you're in last place. Think fast, all the time.
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Re: Question re: sailing downwind leg

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Originally Posted by chip View Post
This is also my experience. I understand the theory of going the long way and jibing, and understand how it's the obvious choice for semi-planing hulls and well-trained crews and stuff, but when flying white sails with most regular displacement hull boats in regular conditions with regular cobbled-together crews, just going wing and wing DDW is a winner.
You are right on. The OP was talking about a Ranger 26. Faster than many boats of that size, but still a displacement hull with, in this case, just a main and jib. However, DDW doesn't always apply. There are many different types of boats. For example, I don't think you would want to sail a Hobie cat dead downwind!
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Re: Question re: sailing downwind leg

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Originally Posted by FreeAgent View Post
You are right on. The OP was talking about a Ranger 26. Faster than many boats of that size, but still a displacement hull with, in this case, just a main and jib. However, DDW doesn't always apply. There are many different types of boats. For example, I don't think you would want to sail a Hobie cat dead downwind!
Totally. Nor a Volvo Ocean 65.

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