Basic tack question

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Quoddy

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Apr 1, 2009
241
Hunter 260 Maine
You can get to your destination with 3 tacks or 30 tacks. How do you know which way is faster?
 
Nov 6, 2006
10,219
Hunter 34 Mandeville Louisiana
Ahhh Haaaa the eternal question !! In perfect conditions where the wind is from exactly the same direction and there is no current, it doesn’t make any difference, except for the speed lost during an individual tack. But ! if you are on one of the three long ones and the wind direction changes, even slightly, you may have put yourself much farther away, or much closer, depending on the direction of the shift (lifted or headed) and where you are along the tack. Generally, that is why racers don’t get a long way away from the rhumb line during tacks to the weather mark in an area where the wind is known to be shifty. This is one that requires some reading and thinking.. and drawing diagrams to visualize .. The Course Made Good (CMG) function in most GPS units can help immensely in solving this one while sailing.
 

Tim R.

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May 27, 2004
3,626
Caliber 40 Long Range Cruiser Portland, Maine
What Claude said and...

When cruising, I tend to go for longer tacks in hoping to find a wind shift. A shift in either direction will be favorable. You either can stay on the same tack and turn more towards your destination or you can sail into the shift a little ways and then tack to a better course towards your destination.

Here in Maine, better wind can often be found further offshore. Less pots too.
 
Feb 26, 2004
23,353
Catalina 34 224 Maple Bay, BC, Canada
It's usually called VMG

Velocity Made Good

The trick it took me 15 years to learn is to set your GPS in the direction of the wind and pick a waypoint 1,000 miles away. This will determine the favored tack based upon where you are heading upwind (your next waypoint) if where you are heading is not directly upwind.

If you wanna learn more, I recommend checking out some How to Race a Sailboat books which explain techniques for getting upwind as quickly as possible.

Eric Hiscock used "the 20 degree cone" but never did clearly define how to use it (i.e., tack within a cone 20 degrees out from the upwind waypoint based on wind alone).

We had a discussion about this on the C25 forum: http://www.catalina-capri-25s.org/forum/topic.asp?TOPIC_ID=20426

It starts out about wind speed, but gets into VMG further down, most of it is on page 2, read on...
 
Feb 12, 2007
259
Ericson 25 Oshkosh, WI
www.sailonline.org is a very good virtual racing site that really helps you understand navigation related to real weather conditions. Give it a try, its free and extremely addictive and fun. It might not look super fancy, but it is the most real simulation of navigational management out there.
 

Joe

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Jun 1, 2004
8,323
Catalina 27 Mission Bay, San Diego
To answer your question, I think the VMG function on the GPS is an amazing tool.
Besides that, knowing what is ahead of you will have a big influence your tacking decisions... by that I mean local knowledge, weather patterns, natural and man-made obstacles that influence wind and current, etc. Being able to read and anticipate the wind shifts is essential. You might want to tack back and forth inshore to take advantage of a land breeze, for instance.

If you read up a bit on racing strategy you'll learn a lot more. Kloudie's comment about staying in the middle during oscillating winds is a good racing strategy when you're ahead, when you're behind I think being more aggressive is in order.
 
Jun 7, 2004
383
Schock 35 Seattle
Agree with all above. Here when the wind is light you can see darker and lighter areas on the water. The dark spots are where the wind is stronger. Strategy calls for putting together the dark spots to the mark. The number of tacks depend on where the wind is.

In high winds where the boat can always sail close to hull speed I agree with the discussion above on headers and lifts.
 
Jan 1, 2006
8,008
Slickcraft 26 Sailfish
Use three tacks if your crew is your wife. Use thirty if you need to punish the crew for insubordination.
 

BobM

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Jun 10, 2004
3,269
S2 9.2A Winthrop, MA
For me? I can't plan thirty tacks ahead...I usually plan for three...and end up closer to six...such as when my recent three tack game plan went out the window due to becoming the unavoidable victim of a squeeze play between a large incoming CG vessel and a medium sized high speed cat ferry...but I'll take a pass on thirty ;-)
 

Quoddy

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Apr 1, 2009
241
Hunter 260 Maine
Tack thanks

Thanks for the ideas on tacks. Some of my ideas were affirmed and I've gotten some new ideas to work with.

I think I will try for highest VMG to destination on port, then on starboard until it is less than I can get on port and then back to port to see how that compares.
 
Dec 4, 2008
264
Other people's boats - Milford, CT
Thanks for the ideas on tacks. Some of my ideas were affirmed and I've gotten some new ideas to work with.

I think I will try for highest VMG to destination on port, then on starboard until it is less than I can get on port and then back to port to see how that compares.
This will really drive you crazy, because the "VMG to the waypoint" will change depending on where you are. What you really want to optimize is "VMG to windward". Use a GPS like Stu said to optimize speed. And sail the longer tack first.

Todd
 
Oct 22, 2008
3,502
- Telstar 28 Buzzards Bay
Of course, many boats lose a bit of speed when they tack, so in that case, the fewer the tacks, the better...
 
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