asymmetrical Spinnaker

[sailingdolphin]

What are the #'s for an asymmetrical spinnaker tall rig?  My I is 46 and my J is 13.6.  my guess is 45.5 and 24.48.

I am looking to do a ATN set up and I would like to race it occassionally.   What are the pro's and con's of a cruising ASym
vs. a racing asym both with an ATN set up?  This is a mark 1

[David Comando]

Hi Doug,
When I purchased Kindred Spirit, 1997, Hull #55 I was fortunate to get an asymetrical chute from the PO. Some advantages to the AS is there is no need for a pole. This reduces the need for extra, experienced crew to fly and trim the chute safely. I added cars to the outside track, and use the jib winches. Trimming is easy as well  as around the outside gybing. I got rid of the sock for dousing as it was more lines, and more chances for things to get stuck. We only use the AS on mild to calm days and for beer can racing and cruising. We save the white knuckle, hang on for your life stuff for J-22 racing where there is need for a foredeck person, and experienced trimmers to keep the painted side down. I don't know the specs for the AS.
Dave

[sailingdolphin]

Dave thanks for your response.

Which one do you think would produce more speed and/ or reaching angle and which one is easier to use?

Asymmetrical or a symmetrical with an ATN tacker?

The way I see it is with the Asymm you can head up to heat up more and go faster typically better VMG but if your
going at approx. 170 or deeper the symmetrical is better.

Do you lose any sail area with an ATN because of the sock at the top?

[Ron Hill]

Doug : The asymmetrical is DEFINITELY easier to use, especially if you are planning on a 2 person crew.  A Mom&Pop operation is not for a symmetrical spinnaker with a pole!!! 
Also get the chute/sock as it's much easier to douse and keep it from getting in the water.  My sock (ShuteScoop) doesn't "steal" any of the air at the head of the sail.  Make sure that your halyard goes thru a block on the mast head bail, so the halyard is in front of the head stay/roller furling.
According to Catalina the "J" on both standard and tall should be 13.5 and the tall rig "I" is 46.00 - for a MKI.     

(I believe that Hull # 55 is a 1986 year C34)

[Mike Vaccaro]

Chutes are optimized for different points of sail--there is no silver bullet.  The asymmetric is the easiest to use, but a symmetric gives best downwind performance on a run.  The cut of an asymmetric can be optimized for either deeper or shallower points of sail.  If you don't have experience with these sails, your best bet is to start with an asymmetric chute that is cut for general use, i.e., optimized for a broad reach.  At the risk of starting a debate, there is a lot to be said for broad reaching with gybes vs. a dead run, even on a windward leeward course!

Rigging an asymmetric is quite simple, and you might want to consider not using the sock at first to familiarize yourself with the basics of handling a chute.  As a minimum, a basic asymmetric only requires three lines, a halyard, a tack (which can be fixed or adjustable--fixed is fine for experimenting and learning) and a sheet.  With a single sheet, it's not possible to tack or gybe the sail; but if sufficient fetch is available, you'll have plenty of time to experiment.  You can add the second sheet, but you'll need to determine whether you intend to tack or gybe the sail at the end of the reach (lazy sheet will have to be rigged outside of the headstay if gybing or inside if tacking).  We tend to gybe an asymmetric to use handling techniques similar to a symmetric; but it's practical in some cases to tack the sail through the foretrangle as well. 

Secure the tack and then run a sheet aft to a turning block mounted to the aft pulpit, then forward to the winch.  It may be necessary to add an inexpensive fitting to your pushpit to allow for mounting of a sheet block if one is not currently installed.  The spinnaker bag should be secured to the pulpit or the foredeck so that it remains with the boat when the sail is pulled out.  Hoisting is simply a matter of jumping the halyard as quickly as possible on the proper tack (i.e., port tack for a starboard hoist--chute needs to be in the "shadow" of the main).   If sufficient crew is available, one person should haul at the mast and one should at the winch.  If your system is low-friction, you may be able to hoist from the cockpit; the goal is to get the sail up as quickly as practical.  Once the halyard is made, then it's simply a matter of trimming the sail.  Without a tack haul, there is likely to be some interference between the sheet and the boom, but you should experiment to determine if a haul is warranted at all on your boat. 

You have the option of dropping (dousing) a chute to the foredeck or cockpit.  This is facilitated by "blowing the tack" (the ATN Tacker is a clever system for use with an asymmetric if you have a furling headsail) and coordinating the halyard drop with the person hauling the sheet.  The trick is to keep the sail out of the water on the way down, which will happen if the halyard drops faster than the sail can be hauled down.  For training, a short line can be made fast to the bow cleat and run through the anchor roller.  There are two options for blowing the tack:  1) simply untie the line from the cleat; or 2) rig the line with a quick release hook that is connected to the tack (you have to be able to reach the tether on the quick release by leaning over the pulpit--so this will limit the length of the tack line above the roller to about 3-4 feet which is sufficient for a learning drill).  Once the tack is released, the person handling the halyard eases as the sail is hauled down.  If a cockpit drop is utilized, the halyard handler and hauler can stand next to each other, simplifying communication. 

Best to read up on the subject a bit and practice on a light day.  Lots of good information to be found on the web, including the sailnet.com archives and north (sails) university sites. 

Once you're familiar the basics of chute handling, then it's time to add the proper rigging and a sock.  This will give you the option of a quick douse (with the sock prior to a tack or gybe which is practical when cruising or racing in heavy weather (when a spinnaker induced broach is possible).  It will also simplify overall chute handling.  Your experience in practicing without a sock will serve you well when things don't go as planned!

We've rigged a symmetric chute without a pole using the ATN tacker on our Catalina 34.  Certainly "doable"--not optimal but it works fine at angles between a beam an broad reach.   If you have access to a symmetric chute, don't hesitate to give this a try.  For lower angles, a flatter asymmetric is the ticket, and for deeper angles, there's no substitute for a pole, but that's when a properly sized crew becomes the key to success!  If you don't have a sail yet, recommend you consider a basic asymmetric and then start with a simple rig, gain some experience and then decide how you want to optimize the rig.  The other option would be to hire a professional rigger to do the lay-out and installation work for you.

The sock will cost you a small amount of area as well as windage and weight aloft.  On the other hand, it will also simplify handling.  As a general rule, the sock lends itself to cruising and racing is best accomplished with proper handling techniques and rig.  But a "general" rule is just that--experimenting a bit will allow you to draw your own conclusions!

Addition of light air sails will give you the ability to sail when you'd otherwise motor--which is a good thing! You won't regret getting a chute.   

Best of Luck!

Mike