Symmetrical Spinnaker Trim

By Andrew Spaulding, Crowley’s Yacht Yard

For those of us out there racing boats with the “old” technology of symmetrical spinnakers, I have a few things to mention that hopefully will help you get the most out of your down wind runs.

To review the basics: 1) The spin pole trimmer (after-guy and fore-guy) is going to keep the pole perpendicular to the wind as a base setting. The spin trimmer (spin sheet) is going to ease the sheet until the luff of the spinnaker curls slightly and trim the sail in when it curves a lot or breaks (starts flapping). 2) The clew (sheet end) and tack (pole end) should be even horizontally, so move the pole up and down with the topping lift and fore guy so that the tack is the same height as the clew. Typically, the deeper you sail down wind the higher the clew will fly. Of course, as you move the outboard end of the spin pole up or down you will need to make a corresponding move with the inboard end to maintain maximum extension of the tack.

Once you have the basics down your trim decisions will largely depend on the conditions. For example one, let’s say you are sailing a deep angle with a following sea. As the driver surfs the waves the boat will accelerate as it starts down the wave and decelerate as the wave passes. As the boat goes faster the apparent wind will come forward requiring spinnaker trim. In large waves, this effect can be large enough to require the pole to be adjusted forward, as well. The best case is when you are trying to sail a lower angle to the next turning mark so that the driver can turn the boat down as the apparent wind comes forward. This will minimize the amount of necessary spinnaker trim. In those situations where you cannot drive the boat down, all the lines that are involved in spinnaker trim (sheet, fore-guy, after-guy, topping lift) need to move quickly to keep up with the changes. There are situations where this isn’t possible, so sail a little over trimmed so that the trimmer has time to catch up as the boat accelerates.

Example two, you are sailing on a tight spinnaker reach in 25 knots of wind. Bring the pole forward so that it is just off of the headstay. In 25 knots, I like to keep it at least a foot away from the headstay so that if the after-guy or fore-guy slips a little while cleating or un-cleating won’t cause the pole to slam into the headstay. You will notice the clew is very low, so get the pole down close to the bow pulpit to match. It is critical for the trimmer to know the feel of the boat because when the boat gets overpowered by a puff and the boat starts to round up into a broach the trimmer must ease out the sheet often very quickly. The more the trimmer knows the boat the more the trimmer will be able to work with the driver to keep the boat upright. Of course, in these conditions a grinder will be necessary…preferably one in great shape.

Example three, you are sailing dead down wind in 12 knots of breeze. Bring the pole all the way aft, almost to the shrouds. Ease the spinnaker out, and then keep going. In the right conditions the spinnaker will rotate out from behind the main, projecting more sail area out in front of the wind. If it doesn’t work, trim in to find your sweet spot. Heading dead down wind in light air can cause a leeward break in the spinnaker if the driver sails by the lee to far. It is possible for a leeward break in the spinnaker to be interpreted by the driver as a windward break causing the driver to steer further down making the problem worse, not better. In this situation, the spinnaker can wrap around the headstay. With quick reaction by the crew to over trim the sheet and after-guy, and by the driver to head up, usually the wrap will come out. If it is a bad one, the driver can alternate between heading up to shake the sail and heading down to hide it from the wind behind the mainsail while the crew is over trimming. If this doesn’t do it, the sail will have to come down to clear the wrap.

Tricks of the Trade: 1) In heavy air trim the spinnaker on the lazy after-guy (not the sheet). Since the after-guy goes through a block near the rail mid-ship this effectively chokes the sail down which will help take some power out of the sail and control oscillations. 2) In medium to light air, take off the lazy after-guy so the sail doesn’t have to hold that extra weight up. In light air, switch to a light air sheet. 3) In light air and not while reaching, ease the halyard a foot to help the spinnaker project away from the boat. 4) Lots of times I’ve seen crews struggle with spinnaker problems for a long time. If you are not making progress towards fixing the problem within 15 seconds, drop the spinnaker on deck, fix the problem and re-hoist the sail – trust me, it will be faster.