Monday 12/20/2010 Question Answered

Paul · Post by **Paul** » Sun Dec 19, 2010 10:15 pm

Amazing... tomorrow, 2:33pm RMST winter officially begins! For you sailors in the southern lattitudes - enjoy while and keep the stories coming for those of us dreaming of warm days, fair winds and the feel and sounds that give life to our boats when underway.

Today's question has to do with setting the sails, and specfically the jib. You've just come about to a new course, not close hauled, just crusing. The main is set and you're now setting the jib for max performance. Your options are to pull in the jib sheet until the leech begins to flutter (showing you're created backflow) and then let it out a bit, or let the sheet out until you notice the jib begins to luff and then haul it back in a bit. Question 1# Which do you choose?

Regardles of what you choose from the above, there's a second question: If your jib luffs first at the top and then works it's way down. The reason is probably:

a) The fairlead is too far forward
b) The luff is too loose
c) The sheet is pulling back but not down enough on the clew
d) The boom vang is not tight enough.

Wherever you are, in whatever clime, I wish you a very merry christmas and a wonderful time of celebration!

Paul

Banshi · Post by **Banshi** » Mon Dec 20, 2010 5:17 am

#1 Assuming you have stolen the telltales off my jib, shame on you, I let it out until it just starts to luff then back in just enough to stop the flutter.

#2 Your jib lead is to far back

Andiron120 · Post by **Andiron120** » Mon Dec 20, 2010 7:34 am

I agree with Banshi.

lecker68 · Post by **lecker68** » Mon Dec 20, 2010 8:40 am

#1 I let it out to Luff and pull it back in to stop flutter.

#2 I would say B and C since they are the same and tightens the foot but will not tighten the leach unless you pull in too far and ruin the foil shape and give yourself excess heel.
good question Paul.

Alanhod · Post by **Alanhod** » Mon Dec 20, 2010 1:52 pm

I'm with Banshi on this one too. No tell tails on the Jib though.

Thanks
Alan

Paul · Post by **Paul** » Mon Dec 20, 2010 9:32 pm

Pretty good so far, although you missed one part of the equation in the original posting - could be that you chalked it up to my inexperience. The rule of thumb, unless close hauled, is to have the sails as far out from the lubber's line as possible. If you spot the overlooked error, feel free to point it out.

To move on, you now come about and are running before the wind, jib to starboard, main to port. How do you want to configure your sails to present the greatest advantage and, in effect, create the greatest wind shadow beyond your craft.

a) Sheet the sails 180 degrees from each other and perpendicular to the wind

b) Sheet the sails 180 degrees from each other and perpendicular to the lubber's line

c) Sheet the main for maximum effectiveness and the jib slightly inboard in order to create some laminar flow over the front (lift) side of the main

d) Sheet the jib for maximum effectiveness and the main slightly inboard to dump wind into the jib

Paul in 50 degree Denver

lecker68 · Post by **lecker68** » Mon Dec 20, 2010 10:19 pm

I would say C otherwise top of head sail will be dumping.

Beady · Post by **Beady** » Tue Dec 21, 2010 7:46 am

I also will jump on the Bansi bandwagon. Does anyone have any pictures of how they handle the jib sheets? I did not use snatch blocks on the rails last year and changes (moving the sheets forward and back) was a pain. A traveler would be great but not in the budget for this upcoming season.

Alanhod · Post by **Alanhod** » Tue Dec 21, 2010 3:51 pm

I'm going with "C" on part two of the question. The 180 Degree from each other is just to far and flat for the best perfomance.

Thanks
Alan

Paul · Post by **Paul** » Thu Dec 23, 2010 9:51 pm

The first part of the problem is in the narrative. Except when running with the wind, always set the jib first and then the main. Again, the rule of thumb is to have the sails as far out as possible except when short hauling.

As for technicque, you are correct that you let the jib out until it luffs and then sheet it back in slightly. The problem with the luff taking place at the top of the jib first has to do with sail shape. To counter this problem the fairlead has to be moved forward. If the bottom portion luffs first, move it back, so answer C) is correct. Because the fairlead is too far back it is pulling back but not down enough to provide the best sail shape.

When running with the wind the correct answer is D). Your jib is much more powerful than the main when running witht he wind. To make maximum use of it the main can be sheeted in slightly which dumps the wind into the jib so once the main has used the energy, the jib get use of it as well.

Merry Christmas to one and all! Fair winds and following seas!

Paul