The J/105 has a relatively small asymmetric spinnaker set on a centerline sprit. The goal in downwind sailing is to maximize downwind VMG. This is achieved by sailing a wind angle tight enough to keep speed, but sailing lower towards the mark whenever possible. The North Sails asymmetric has been designed as a running spinnaker for optimum downwind performance at the apparent wind angles that produce the best VMG for the J/105. The sail has been designed to rotate out to windward to project the maximum sail area out from behind the mainsail. Always hoist the sail all the way to the top. Due to the luff length restriction in the rules, the tack of the sail is never set all the way down to the pole. Raising the tack helps the sail to rotate to windward.

Light Air Sailing (0-9 knots TWS) In light air, you must sail tighter angles for best VMG. The tack is set 2.5' off the sprit. The crew should be forward and to leeward. Keep the crew weight as low as possible. Steer down in the puffs until the pressure sheet starts to get light and then head up slightly. Communication between the trimmer and the helmsman is key. Try to find the lowest angle you can sail before the speed drops. Don't forget about the main! Proper mainsail trim is essential to good speed. The vang should be set so that the top batten is open by 5 degrees.

Moderate Air Sailing (9-12 knots TWS) In moderate air, there is a wide range where you can sail. Lower is best as long as you can maintain your speed. The tack line is eased 3-4' off the sprit. The same principles apply to steering as in light air. Once the boat feels well pressured, the crew should move to the windward side to help rotate the spinnaker. In this range the crew should be very active moving to weather when you head down in the puffs and back to leeward when you head up in the lulls.

Heavy Air Sailing (12+ knots TWS) In over 12 knots, the boat is well pressured up going downwind. At this point you want to sail as low as possible most of the time. There will almost always be good pressure on the sheet but when you sail too low, the sail will become blanketed behind the main and collapse. The sheet is well eased to get as much of the sail out from behind the main as possible. The crew should be to windward at all times. Heel the boat to windward by as much as 10 degrees. The vang should be set so that the top batten is parallel to the boom.

*Downwind Notes - Good coordination between the trimmer and helmsman will result in very subtle changes in the sheet. A properly coordinated team will only adjust the sheet by a couple of feet. If you find yourself constantly trimming and easing more than 3 feet of sheet than your coordination should be improved. Be careful not to try to sail too low and collapse the spinnaker. A collapse will result in around a three boat length loss!