The basic idea of trimming a wingmast rig is to effectively make the mast part of the sail. To do this, the leeward side of the mast is faired into the shape of the sail. Below is some general advice on the trimming effects and recommended settings for different conditions.
Luff tension
The tension on the luff is controlled by pulling the downhaul (cunningham). This prebends the mast flattening the sail, while at the same time the tip of the mast moves back, shortening the distance between the clew and the head. This loosens the leech and allows the leech to fall away. The effect is less power and less drag.
Mast rotation
Reducing the mast rotation has the effect of allowing the top of the mast to fall away, causing the leech of the sail to open up, reducing the power and hence heeling moment. The reduction of rotation also lessens the effective draft of the sail, reducing both power and drag. Note: More rotation above the optimum described below increases both heeling moment and drag, so you need to be very mindful of increased drag in this situation.
Mainsheet tension
The main effect of mainsheet tension is to control the twist of the sail. As on other boats, the mainsheet is used for most of the fine adjustments when sailing.
Upwind sailing
Very light winds: 1-4 knots
Lie close to the mast and over the front beam. Keep the transoms out of the water and concentrate on keeping flow on the sail.
| Luff tension | Firm downhaul, open the leech |
| Mast rotation | 45 degrees |
| Mainsheet | Light, all telltales should be flowing. Twist the sail off. |
| Foot | Tight |
| Traveller | Centered |
Light winds: 4-8 knots
Tell tales all leeward must flow and all windward (the ones close to the luff) flowing about 60% of the time
You should be hiking hard and be out on trapeze from about 6 knots. Trapeze forward of the front beam to keep bows down but move back to opposite the side stay in the puffs. Bear off in the puffs and point in the lulls.
| Luff tension | Just enough to take out the wrinkles |
| Mast rotation | 45 degrees |
| Mainsheet | Moderate to firm as the wind builds |
| Foot | Freed about 30 mm (just over an inch) |
| Traveller | Centered |
Medium winds: 8-14 knots
| Luff tension | Just enough to take out the wrinkles. Pull if you start to get overpowered. At 12 knots tension is hard. |
| Mast rotation | 40 to 35 degrees |
| Mainsheet | Firm to hard, to stand up the leech for maximum power |
| Foot | Flat |
| Traveller | Centered |
Strong winds: 14-20 knots
| Luff tension | Pull hard to flatten the sail as much as possible and then some |
| Mast rotation | 35 degrees, bringing to 20 degrees in high winds |
| Mainsheet | Firm to hard, however ease about 250 mm (10 inch) in stronger stuff and just go for speed |
| Foot | Flat and tight |
| Traveller | Centered, or drop to 20-50 mm (1-2 inch) in stronger sinds to keep the boat flat |
Downwind sailing
Very light winds: 1-4 knots
Boat is sailed flat. Keep your weight forward to make sure the transoms are not dragging.
| Luff tension | Firm for shape and flow. As soon as there is some pressure, ease to take out wrinkles |
| Mast rotation | 90 to 100 degrees |
| Mainsheet | Light, allow sail to twist and keep leeward telltales flowing |
| Foot | Ease to give 150 mm (6 inch) of camber |
| Traveller | Out as far as it will go |
Light winds: 4-8 knots
Boat is sailed flat. Keep your weight forward to make sure the transoms are not dragging.
| Luff tension | Ease to take out the wrinkles |
| Mast rotation | 90 degrees |
| Mainsheet | Ligh to firm, to control the leech twist or maximum power. All telltales should be flowing. |
| Foot | Ease to give 150 mm (6 inch) of camber |
| Traveller | Out as far as it will go |
Medium winds: 8-14 knots
Ideal “Wild Thing” mode range. Steer down in the gusts and up in the lulls. More your weight middle to back and to leeward to help lift the windward hull.
| Luff tension | Just take out the wrinkles |
| Mast rotation | 80 degrees |
| Mainsheet | Firm to hard, ease in gusts to control the power in the sail |
| Foot | Freed to give 50 mm (2 inch) of camber |
| Traveller | Set to 100 mm (4 inch) up from inner gunwale |
Strong winds: 14-18 knots
“Wild Thing” mode. Steer down in the gusts and up in the lulls. Move your weight back. Smooth is fast.
| Luff tension | Pull slightly to induce twist in top of the sail |
| Mast rotation | 80 degrees |
| Mainsheet | Firm to hard, ease in gusts to control the power in the sail |
| Foot | Freed to give 50 mm (2 inch) of camber |
| Traveller | Set to 100 mm (4 inch) up from inner gunwale |
Very strong winds: 18+ knots
Sail the boat flat and deep. Pointing higher will not increase your speed, you are already at maximum hull speed. Steer down in the gusts and up in the lulls. Move your weight back as far aft as possible on the windward hull.
| Luff tension | Pull firmly to induce twist in top of the sail |
| Mast rotation | 80 degrees |
| Mainsheet | Tight as you are game, ease in gusts to control the power in the sail |
| Foot | Pull flat, same as upwind setting |
| Traveller | Out as far as possible |