Wednesday, May 25, 2011

Sonar Class Association Newsletter, May 25, 2011






Regattas:


The Nyack Boat club hosted another successful Tappan Zee Challenge this past weekend (May 21-22). A total of five races were completed with Skip Shumway posting a dramatic come-from-behind victory after posting two 9's the first day.

Second and third went to the United States Merchant Marine Academy with Rick Dominique taking second and Midn. Joe Hoffman, in another day two come back, finishing third

After that, the next five boats, all from Noroton YC, were separated by a total of only four points.

The conditions were challenging, the racing tight and a great time was had by all.

Full results:

Click on the image to enlarge


Next up, the Long Island Sound Championships on June 4-5, hosted by Manhasset Bay YC's fleet 11 and the USMMA's fleet 22. There is still time to register at http://www.sonar.org/

Team Racing:

The Oyster Bay Challenge, hosted by Seawanhaka Corinthian YC, was held on May 14-15. In addition to the host team, another four teams participated including 2 from New York YC, one from Noroton YC and one from the Nyack Boat Club.

The weather was rainy the second day, but overall the conditions were excellent for team racing with adequate and relatively steady wind.  At the end of the first day NYYC 1 was in first with six points. After that there was a three-way tie for second with NYYC2, Seawanhaka and Noroton.

Day two saw things shake out a little with NYYC1 winning the event followed by NYYC 2, SCYC, Noroton and Nyack.

Rules:

Here is our next rules question from U.S. Sailing Senior Judge Peter Wilson...

Click on the image to enlarge
Peter's answer:

Yellow does not break any rules. She is entitled to mark-room from blue and as windward, keep-clear boat, mark-room includes sailing a seamanlike course to the mark. So long as she sails this course directly to the mark, as she is doing in positions 2 and 3, she will be exonerated if she breaks rule 11 (windward/leeward) with respect to blue. When blue slows and separates from yellow, between positions 3 and 4, yellow may widen her approach to the mark so long as she still keeps clear of blue which she does a position 4 and then again at position 5 when blue heads up. If, however, she makes contact with blue or forces blue to avoid contact as she widens her approach, then she breaks rule 11 and does not receive any exoneration.

Go Fast:

From time to time, we hope to post "go fast" articles from members. Here is the first from Lee Morrison, Noroton YC fleet 1 member:


Forestay Length

Debating forestay length is a time honored tradition in many classes but none more so than the Sonar.  With its relatively limber rig and large sail plan the length of the forestay greatly influences the power of a Sonar’s rig.

Forestay length is one determinate of jib sag which affects the amount and location of draft in a jib.  As we know, you want flatten sails in heavy air and add draft/make the entry finer in light air/flat water.  So, if we agree that the length of the forestay influences the shape of the jib and that we can improve the performance of a sail by changing its shape in different wind conditions, why are so many Sonar forestay turnbuckles pinned down and taped up never to be touched after winning some race back in 2006?

Granted, other controls such as mast blocking, influences jib sag as much or more than forestay length.  Moving blocks is certainly easier than changing forestay length and, blocks can be adjusted while racing.  But, after setting your mast blocks correctly (refer to your sail maker’s guide), changing your forestay length can provide some extra power when you need it in chop, a finer entry when the water is smooth, or make the jib flatter when it gets windy.  If you are not convinced that small changes in forestay length (a bit more than an inch in either direction using the adjuster mentioned below) can make a difference, the next time you sail your boat in heavy air look at your forestay and visualize how sag is adding unneeded power to the jib.  Think about the amount of tension on the forestay – hundreds of lbs of pressure.  Then imagine how much sag would be removed if you could easily make the forestay just one inch shorter.

If this sounds like something you would like to explore then read on.  Here are some tips picked up from experimenting with forestay length last summer.

1) You need to make your forestay easy to adjust on the water between races even when it’s windy.  Believe me, when it starts getting rough, you don’t want to be on your foredeck cutting off tape and pulling pins.  I use a ? Hold Allen High Load Calibrated Adjuster HA4772H ($42.95 at APS) and Ronstan RF115x3/4 Toggle Pin ($16.95 at Jamestown Distributors).  Sailing downwind between races I can easily and accurately make 1/4” adjustments even in the windiest of conditions.  You will need a new forestay ‘wire’ since cutting off the existing turnbuckle would make the current forestay too short for the new adjuster.  Here’s a bonus tip if you have a 3.8mm backstay – the diameter that typically comes standard with a new boat.  The rules allow a slightly narrower diameter backstay - 3.0mm (rule F.7.6 (d)).  If you purchase a new minimum diameter backstay you can repurpose your existing backstay making it the new forestay.  The current backstay end fitting should fit into your new adjuster.  Set it to the mid point and then have a new t-ball fitting swaged on at the desired length (see tip #2).

2) If you feel that your boat is fast, measure your current forestay length to use as a reference.  If not, start with the number provided in your sail maker’s guide.  Make that the length of the new forestay with the adjuster pin at the midpoint in your forestay adjuster.  Make sure that when the adjustment pin is at the top of the adjuster that the forestay is less than the class allowed maximum length.  Similarly check the minimum length with the adjustment pin at the bottom of the adjuster.

The rest is easy.  If its light air and flat water move your adjustment pin up a little bit (try 1/2”) from the midpoint.  All else being equal, that will increase jib sag resulting in greater power.  As the breeze picks up move the adjustment pin down.  The next time the wind speed gets to the point that you believe that the crew will be on the rail most of the time going upwind – for example, the last day of last year’s North Americans, try sailing with the pin at the bottom of the adjuster - ~1 1/4” inch shorter than your sail maker’s ‘all around’ setting.  You’ll feel the difference!