Rigging and Gybing With an Asymmetric
Sailing with asymmetric spinnakers on sprit boats has become common in the last 10 years but there is a growing trend of using asymmetrics on conventional boats with standard spinnaker poles. While these sails are very efficient they do require somewhat different rigging, and gybing them is quite different.
First let’s look at the different rigging that is required. The biggest differences are that you need a tack line instead of a foreguy on the pole, two afterguys that both go to the tack, and two spinnaker sheets that both attach to the clew. The tack line needs to go through a block right at the headstay or with an oversize pole at the point that is the same distance from the mast as your spinnaker pole length. On smaller boats the tack line attaches directly to the tack of the asymmetric using a snap shackle with a large bale. The two afterguys are snapped on to the bale of the tack shackle. Larger boats often use a large stainless steel ring with bars welded across it in an “X” pattern. The tack line attaches to the bottom section, there are two snap shackles in the top section to attach to the tack of the sail so you can do peels, and the afterguys are attached to the two side sections. Spinnaker sheets should tied to the clew rather than attached with snap shackles; during gybes there is an increased possibility of the shackles coming open as the sail is pulled across the headstay or around the luff, and there is also a much greater possibility of the shackles ripping the sail as they are dragged across it. A “Y” sheet is widely used and consists of two sheets connected with a single short tail that is tied to the sail with a bowline. This reduces the drag during the gybe.
Sailing with an asymmetric on a pole is no different than sailing with a symmetric. You still pull the pole back the same amount and sail the same angles as you do with your symmetric, the sails are just slightly more efficient when sailing deep because they have longer luffs and shorter leeches which gets more sail area out on the weather side of the boat where it does the most good. The downwind asymmetrics, a Code 2A or Code 4A, will generally be maximum size and have a mid-girth that is the maximum for your rating. The shoulders will be just as big as a symmetric. Sailing with the apparent wind forward of the beam, either sailing vmg downwind angles in light air or because a set course requires it, the asymmetrics are noticeably better because of their asymmetric cross-sectional shape. These sails will be built with a mid-girth that is shorter than the foot, be flatter, and have much straighter leech sections. This allows them to be sheeted in tighter without forcing nearly as much wind into the back side of the main and be more open leeched so the power is utilized to make you go forward faster rather than heeling over more.
The major difference in sailing in sailing the asymmetric with a conventional
pole is in gybing them. Since you are flying the sail on a spinnaker
pole instead of a sprit the pole has to be gybed the same as with a
symmetrical. While this is taking place the asymmetric has to be tacked
to the bow. The first step is to “Transfer” the tack. This is done by
easing the afterguy forward while the tack line is taken up to pull
the tack down to the bow. If you are sailing in light or medium air,
any time the apparent wind angle is forward of about 135 degrees, you
can maintain your sailing angle during this operation. In heavier air
when you are sailing deeper you may have to head up some to get to an
angle where the sail with still fly when the tack is transferred to
If you haven’t sailed on a boat with an asymmetric on a pole this all may sound a little complex; but it really isn’t, it’s just different. With a little practice you crew will soon be will be able to gybe the boat just as efficiently as they did before.