Conference unifix::sailing

    A sloppy jib luff produces a sail shape that's fuller with a more
    critical entry and the draft farther back than you would get with a
    tight luff.
    
    For an Etchells, which is relatively heavy for the amount of sail it
    carries, such a sailshape gives simultaneous power and pointing at the
    expense of ease of steering.  When there are waves on water, which
    there usually are when it's blustery, the power is needed to punch
    through, especially if a heavy flat jib is being used.  E22 jibs aren't
    normally changed during a race.  Playing with the jib luff is one way
    to get a bit more range out of one sail as conditions change.
    
    - gene

    Another reason to wrinkle the luff in heavy air-
    
    If you want to shift into point mode, easing the jib luff tension
    to flatten the entry is better than tightening the backstay (more
    than normal) and de-powering the whole sail plan.

    Re: -.1
    
    Exactly!  This is especially true with a fractional rig.  You don't
    want to flatten your main out by tightening the runners too much.  You
    could offset this with checkstay tension, but why load up the boat
    unnecessarily?  We thought this was counter intuitive at first also. 
    But we tried it and it works.
    
    Also, our sails take on different looks with varying backstay tension
    even if we don't touch halyard tension.  If we ease backstay (say on a
    reach) the headsail will look baggy on the forestay as the stratch has
    been taken out of it.  
    
    Everybody knows that an ugly main is a fast main.  Now we may have to
    extend that to headsails!
    
    Dave

    Thanks.  Getting some interesting perspectives.  Biased
    towards frac, but still helpful.
    
    I guess I'm still incredulous, however, that a hanked
    on jib with scallops running the entire luff is fast
    as compared to enough tension to take them out.  The same
    goes for wrinkles along a headfoil and a sag at the bottom.
    This in heavy air without significant chop.  Guess I'm anal 
    retentive, but I like a cleaner entry.  
    
    Re:  Ugly is beautiful
    
    Where's that delivery main?
    
    ;)
    

    In the Soling we use this technique since Buddy Melges learned us to
    sail the boat with a lot of jibstay sag. Actualy we like to have the
    halyard as loose as possible without wrinkles. But it is easier to see the
    difference between a little wrinkle and a lot of wrinkles than it is to
    see between a little tension and a lot of tension. So to be on the save
    side we sail with wrinkles.
    
    
    Rudy den Outer
    Soling H-22

    The luff wrinkles aren't always faster.  And the pointing isn't really
    better.  When the halyard tension goes away, the luff flattens out so
    the groove narrows.  The telltales always want to rise so it looks like
    you're pinching.  But the compass won't show that you're actually
    sailing higher.
    
    The middle part of the jib has to get fuller since the cloth must go
    somewhere.  This gives more depth but not really in the part of the sail
    that needs it and the shape is not especially fair.  This is a way of
    getting more power out of a too flat sail without changing it.  On a
    big boat when the # 3 is up but the wind really wants a # 2 and you
    don't want to sacrifice the pointing that's inherent in the # 2,
    wrinkles in the jib make sense.  
    
    Steering with jib wrinkles is hard.  Too easy to stall out and that's
    decidedly slow.  I prefer to take the wrinkles out and manage sail
    depth with forestay sag.  
    
    An alternative is to use a full sail and keep it stretched to depower. 
    When you need the fullness, ease off a bit on the luff, sheet, and
    stay.
    
    - gene
     

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Note 1788.7                      Halyard Tension                          7 of 7
SWAM1::FERGUSON_BR                                   42 lines  16-JUN-1992 17:14
                          -< Halyards control draft. >-
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    One important note to realise regarding helyard tension, IT CONTROLS
    DRAFT LOCATION. This is the main reason that you need to change halyard
    tension. A forward draft gives power, less pointing, a draft aft gives
    less power, better pointing.
    
    An additional effect is that as the wind picks up the draft goes aft.
    This means that to get the draft in the same location, more halyard
    tension is needed. 
    
    The reason that boats like Etchells and J-24's use wrinkly jibs, is
    that class rules limit the sails used on the boat. Thus the Fore Sails
    have to work accross more of a range, as such they are cut with the
    draft 4-6% further forward than a single range sail. So at the low to
    medium wind strengths, they use as slack halyard.
    
    I learned to remember this when I was sailing my J-24, and winning the
    regatta, until I left the scallops off. I was almost immediatly
    overtaken by a competitor with big scallops. I eased my halyard, and
    was back in the race.
    
    Remember, to win races, its not what the sails look like that count,
    but how you are doing relative to the others around you.
    
    
    I.e. If you are faster forward, but hull down, de-power and pinch.
    
    	 if you are pointing better,but slower, power up and reach more.
	
         if you are slower, and badly pointing, reach, then make the sails
    more effective. (you have to have speed to point!)
    
    
    PS I got a third in the regatta, (the wind went left, when it should
    have gone right!!!!!)
    
    
    Good luck out there.
    
    Bruce
    US 848