Are sail comparisons bunk?

Discussion in 'Sailboats' started by misanthropicexplore, Oct 28, 2020.

  1. misanthropicexplore
    Joined: Apr 2018
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    Location: Upper middle Missouri River

    misanthropicexplore Junior Member

    Short version:

    A sail is a single part of a highly integrated system. Is it even possible to realistically compare different sails if they are parts of radically different integrated systems?

    Long version:

    So, I guess this is more of an attempt to write an essay than a question. . I'm just some guy on the internet, self educated, with little sailing experience. My wife says I learn by pontificating, so I apologize in advance if my tone comes across as preachy. I'm not trying to be a "know it all". I know very little. I'm sure that if I'm right, most of you already know all this and reached this conclusion a long time ago. I just really want some input on my take to see if I am barking up the right tree.

    I can find scientific, or at least scientific seeming papers, written by much smarter people than I, which say that the Bermuda is best for most sailors, doing most sailing. But I find papers that say this about the crab claw or even the spritsail. I can also find an abundance of claims that the wingsail is going to replace the conventional sail "sometime next week" which go back to the 1930's, , and newspaper/magazine articles going back to the late 70's that say the rig of the week (take your pick between Balestron, Dynarig, Princeton Sailwing, rigid wingsail, kitesail etc.) are going to be on every cargo ship in another 10 to 15 years. Always there is a test, a shoot out, a new patent or a case study that proves the headline.

    There also seems to be this idea that the any other rig could as good or better than the Bermuda, if the same design effort was put into it, and that effort is not put in because of some sort of purposeful or incidental conspiracy by racing bodies and handicappers.

    It looks to me like all these tests miss about 4 basic concepts:

    (1.) Adjustment/test method
    (2.) Rigging
    (3.) Integrated system
    (4.) Available materials

    Adjustment/test method:

    Bermudas are almost infinitely modifiable with all sorts of add-ons and subtractions. Tests where the Bermuda doesn't win always seem lock the Bermuda into a spot that make in an unfair comparison, like down wind sailing without a spinnaker or exclusively in high wind.

    Rigging:

    Bermudas have a lot of wire in the air. Tests where the crab claw or the spritsail beat the Bermuda always seem to pair an fully stayed Bermuda against a high tech unstayed crab claw or spritsail, instead of an equally high tech unstayed, Bermuda against a high tech unstayed crab claw or spritsail.

    Integrated systems):

    It seems to me that for best results the strengths and weaknesses of a hull, the rig, and the rigging all have to be complimentary. A high aspect ratio rig with lots of stays pairs best with a very different kind of hull than a low aspect ratio spritsail with no stays. It seems like a truly "fair" test would be boats of equal displacement, with hulls equally maximized for their particular rig's quirks, like where the center of effort is, and the ratio of righting moment that comes from hull form vs. ballast weight. But then, the boats would be so radically different as to to make the test no longer an apples to apples comparison.

    Available materials:

    We have the materials now to make just about any size and shape of mast, spar, or sail, and the labor savers to let to move them in reference to each other about any way we want. Take whatever traditional rig you like and use it as an inspiration to build something kind of like it with modern technology. For instance, the lateen. People will say "it's a modern lateen rig.". But is it? Compared to the original, you don't have the same limits on strength to weight ratios, spar length, sail strength, rigging quantity or quality, analytical tools, or profitability. It's a single skinned, low aspect ratio, moderately sharp leading edge delta form airfoil. We don't call an iPod a "modern phonograph" after all.

    Take that "lateen inspired" design, and design an ideal hull for it, and you'll have a boat that, under some certain test condition, will beat an equally maximized "Bermuda inspired" design (because a 21st Century Bermuda with aluminum, carbon fiber, and dyneema just doesn't have a lot to do with the 17th century original design) that is properly integrated. Alternately, make sort of "universal hull" that isn't really maximized for any particular rig or rigging type, and slap a modern, not fully maximized rig of any type on it, and they will all preform about equally because of the lack of integration.

    This lead me to see two things:

    (1.) In an apple to apples comparison, the Bermuda inspired sail always wins.
    (2.) *There ain't no such thing as an apples to apples comparison.

    No matter how it's broken down to the do the comparison, I'm not sure different rigs can be fairly compared. If the whole hull/rig/rigging system is fully integrated, then the integrated systems are too different to compare fairly. If the hull/rig/rigging is badly integrated enough to allow the use of any rig, then the unrealistically bad integration is to far from the real world to compare fairly.

    Are sail comparisons pointless?

    I might add, the standard thing that always comes up with the Bermuda is windward performance. The thing is with that, the Bermuda will not perform to the windward all by itself, it performs as part as an integrated system. The Bermuda is only better at going down wind than other systems if you count the spinnaker. If we can just add another sail, which works via different principals, and different attachment points, then why can't we add an outboard? Why is the addition of a spinnaker to the system still "fair" but the addition of outboard to it isn't? Can any real comparisons between individual components in highly integrated systems be made?
     
    Last edited: Oct 28, 2020
    Blueknarr likes this.
  2. messabout
    Joined: Jan 2006
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    Location: Lakeland Fl USA

    messabout Senior Member

    Yes, sail comparisons are pointless because thee are so many variables involved.

    Are we more interested in : Windward performance, off wind performance, ease of management, cost, complexity of the rig or absence of complexity, durability, ease of repair, choice of materials used, soft sail or full battened. does it need to have reefing ability, and a whole mess of other questions to answer. The selection of a sail type is a "horses for courses" kind of thing. Add to the variables that there is the personal preference variation. Michael Storer likes lug sails, I like sprit boom sails but i also like the swing rig, my friend Jerry, a racer type, wants a tall and expensive, sloop rig, The AC75 needs wing sails and an elaborate computerized trim information system to wring out optimum performance, The Sunfish works pretty well with a lateen rig, John Leather was evident;y a fan of Gaff rigs, etc....

    Phil Bolger did a little book that described a hundred different sail types and combinations. He remarked about the plus and minuses of each of them. Tom Whidden's book: The Art And Science of Sails is a pretty good read.
     
  3. misanthropicexplore
    Joined: Apr 2018
    Posts: 72
    Likes: 6, Points: 8
    Location: Upper middle Missouri River

    misanthropicexplore Junior Member

    So I am barking up the right tree then, as it were. :)

    I'm frustrated with myself for reading these articles, and those kind of books (though the Widden title is new to me and I'm looking forward to reading it now) for years and not getting it. With enough effort, finesse, money, and inconvenience you can make about anything do anything. "General Performance" wasn't the cause of any historical sailing rig: materials and circumstances was. A wind turbine charged electric outboard can be just as much a single piece of a use-the-wind-to-go-a-certain-way device as a fin keel or a spinnaker.
     
  4. Blueknarr
    Joined: Aug 2017
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    Location: Colorado

    Blueknarr Senior Member

    You pretty much nailed the head of the hammer.

    Add to the mix miopic zialots who exaggerate claims. Or believe that if a rig is better in one instance on one style or design therefore it's best for all designs and conditions.

    Personality I think the Bermuda is the best all round general purpose winner. But sometimes another style suits a particular need better.
     

  5. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    You can compare turtles to sails. The key to useful comparisons is to establish the parameters or characteristics to be compared, and how much influence each has in the total value. There are different systems that can be used. For example, comparison matrices help to put a value to the items to categorize them.
     
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