View Poll Results: What should they do?

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  • Shut the whole thing down and fix it for Chrissake

    16 76.19%
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    5 23.81%
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  1. #1
    Join Date
    Jun 2004
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    1,886

    Default How do you optimize your upwind performance?

    Freestyle did pretty well on her most recent cruise, with head winds for only six of the fourteen days and insufficient wind for two. The highly implausible figure of six days of fair winds might at first glance appear to upset the well-established Scuttlebutt dogma that there are only three sorts of wind: too much, too little or from the wrong direction. (We cheated, of course, by choosing an itinerary to suit the forecast wind.)

    But head wind days do tend to drag a bit, giving the opportunity for the crew to indulge in a bit of competitive, er, knowledge-broking, sometimes less politely referred to as bullshatting. One of our more vigorous discussions arose out of one of Freestyle's less endearing characteristics: she lacks a nice sharp cusp letting the helm know when she's nicely on the wind. I like to sail fast and free, but keen young crew members generally feel the need to pinch up and up until we start loosing way. We discussed the utililty of the VMG (velocity made good) displayed by Charlie Chartplotter. This VMG was actually the vector of the speed resolved in the direction of the (upwind) waypoint and therefore, however well you sailed, gradually declined from the potential maximum (dead downwind of the waypoint) to zero (when the waypoint was 90 degrees dead abeam). Freestyle's on-board mathematics graduate reckoned that using Charlie's VMG to optimize upwind sailing therefore made sense only when one was dead downwind of the waypoint - it makes you pinch progressively as the waypoint comes abeam.

    Old Phil the ageing AP Navigator was much more canny, although to be fair he did have feeds, on wind direction and speed, to which Charlie was not party. Phil's VMG is the vector of the speed over ground resolved in the upwind direction. He even plots a curve showing how the VMG changes with angle on the wind, although you have to redraw it after every occasion on which the engine is used to go upwind. For real time optimization of upwind sailing, however, Phil is no more use to the helm than Charlie because his VMG is only visible at the chart table.

  2. #2
    Join Date
    Jul 2006
    Posts
    2,752

    Default Re: How do you optimize your upwind performance?

    If you put in a fictional waypoint several hundred miles directly upwind, you get a pretty good quick and dirty guide to whether pinching or fast and free are best, and unless you have an exceptionally fast boat it keeps working for qite a while.

  3. #3
    Join Date
    Jan 2004
    Posts
    2,068

    Default Re: How do you optimize your upwind performance?

    I messed up and only voted for feel but meant to include the two for telltales. I also mess about with VMG but with a wee boat, particularly in a fresh breeze, I'm either going to windward a wee bit or hardly at all and it's fairly easy to tell the difference. [img]/forums/images/graemlins/smile.gif[/img]

    It's a good question however and I'm eager to pick up some tips from this thread.

  4. #4
    Join Date
    Mar 2005
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    15,513

    Default Re: How do you optimize your upwind performance?

    I do a combination of things, but mainly looking at the genoa telltales and the mainsail shape, and looking at the wind indicator. One useful trick on my boat is to put the autopilot on, and trim the sails so that the rudder is amidships, on the principle that a balanced boat sails best. That usually means having to bear away little as it is difficult to achieve good balance if pinched up too much, and results in more speed.

    On my boat the bimini makes it hard to see the masthead indicator without leaning back a long way, but I do it from time to time.

    On my recent trip to Turkey I think about 75% of my sailing was upwind.
    Comparison with other boats where I sail does not work very often as so many of them are charter yachts, frequently with inexperienced skippers, and generally with poor sails, e.g. baggy old genoa and in mast main, and simply do not point as high as my boat with a (smaller than standard) tri radial genoa and a new fully battened main.
    Working on immortality - One day at a time.

  5. #5
    Join Date
    May 2007
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    17,170

    Default Re: How do you optimize your upwind performance?

    Jib tell-tales are the primary tool.
    Second is speed through water.
    VMG must be used with great caution as it involves averaging and is backward looking. You can fool the VMG readout by stuffing up to weather, VMG will climb as your heading is higher, but your speed will slowly decrease.
    Sailing alongside a similar boat is the best indicator!

  6. #6
    Join Date
    Mar 2005
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    15,513

    Default Re: How do you optimize your upwind performance?

    I don't actually bother with VMG although my old VDO Siemens instruments actually give me VMG against the true wind direction rather than against a waypoint, provided you don't enter a waypoint. In my experiece I can outsail most similar boats upwind, simply because I have decent newish sails.

    I have regularly found that I can start off downwind and behind another boat and overtake it on the upwind side. I do not normally try to pinch up too close to the wind, but on a recent trip from Gocek to Loryma the wind (when it finally arrived) was almost dead on the nose and I elected to go on the port tack and keep as close to the wind as reasonably possible. Another boat about the same size as mine was ahead of me and well upwind, but elected to sail on the same tack, but further off the wind. They crossed ahead of me and made their tack before me, but by then well downwind. When I tacked the wind rose rapidly to 35 knots, gusting 40 plus, and came round to head me so I motored the last few miles, as did the other boat, and we arrived only a few minutes apart. At the point where we dropped the sails completely I was probably marginally closer to our destination but there was not much in it. Very different tactics over 30 plus miles of sailing had produced very similar results.
    Working on immortality - One day at a time.

  7. #7
    Join Date
    May 2007
    Posts
    17,170

    Default Re: How do you optimize your upwind performance?

    There are a lot of variables in sailing upwind. The wind direction will change, particularly if an increase in strength occurs. Being the right side of shifts is as important as boatspeed or pointing.
    A 2% difference in boatspeed is a lot, but it will be cancelled by a 12 degree windshift.
    And then there's the tide...

  8. #8
    Join Date
    Mar 2005
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    Default Re: How do you optimize your upwind performance?

    Windshifts? On one occasion the forecast was for a westerly, going north-west later. I needed to go almost due west, and needed to set off in order to complete the trip at a reasonable hour. I figured that if I set off on the port tack, sailing north west then I could tack once the wind had shifted a bit to the north, and would probably finish the trip sailing south west on a beam reach. This would entail one long leg on each tack, and take me a considerable distance away from a straight route, which is only a good idea if you are confident that the wind predictions are correct.

    The best laid plans...
    My plan did not quite work out. At first it was OK, 15 knots of wind from the west and I made good time almost due north-west getting close to the point where I was north-east of the destination and I tacked a bit early to sail south-west. Just after that the wind dropped a bit, then started blowing again from the south-west!

    As you say, a wind shift can undo any plan, particularly if it goes the opposite way from the forecast.
    Working on immortality - One day at a time.

  9. #9
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    Slow_boat is offline Registered User
    Location : My own cosy little world where nice things happen and life is beautiful all the time
    Join Date
    Sep 2005
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    Default Re: How do you optimize your upwind performance?

    I don't know what velocity made good means and please don't explain. It will make it all sound over complicated, like articles on tide or taking a bearing, and reduce what is a pleasure to a boring maths class.

  10. #10
    Join Date
    Jul 2001
    Posts
    21,322

    Default Re: How do you optimize your upwind performance?

    [ QUOTE ]
    I don't know what velocity made good means and please don't explain. It will make it all sound over complicated, like articles on tide or taking a bearing, and reduce what is a pleasure to a boring maths class.

    [/ QUOTE ] Erm . . . didn't you forget to put a smiley in here?

    - W

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