Sail settings to reduce rounding up The best way to reduce rounding up in an over-canvassed boat, is to reduce sail by reefing, lowering or furling. If this is not possible due to rig design, for example, then sail adjustment may reduce or prevent rounding up when beating to windward. For a fore-and-aft rigged craft: The vang may be loosened, the mainsheet traveller moved to windward, or both, to allow the boom rise The mainsheet may be loosened to spill wind Allowing the boom to rise increases the twist in the mainsail, which spills wind higher in the sail while keeping power in the bottom of the mainsail to maintain the effectiveness of the rudder. If a boat tends to round up when the helmsman is attempting to sail straight downwind  , and you cannot reduce sail area, but the boat is manageable on the other points of sail, then the only solution is to avoid that situation by tacking downwind. This means you do not head straight for a downwind destination, but rather follow a zig-zag course, reaching your downwind destination through a series of reaches  .
Sail settings to reduce rounding up The best way to reduce rounding up in an over-canvassed boat, is to reduce sail by reefing, lowering or furling. If this is not possible due to rig design, for example, then sail adjustment may reduce or prevent rounding up when beating to windward. For a fore-and-aft rigged craft: The vang may be loosened, the mainsheet traveller moved to windward, or both, to allow the boom rise The mainsheet may be loosened to spill wind Allowing the boom to rise increases the twist in the mainsail, which spills wind higher in the sail while keeping power in the bottom of the mainsail to maintain the effectiveness of the rudder. If a boat tends to round up when the helmsman is attempting to sail straight downwind ("running down before the wind") , and you cannot reduce sail area, but the boat is manageable on the other points of sail, then the only solution is to avoid running down before the wind by instead tacking downwind. This means you do not head straight for a downwind destination, but rather follow a zig-zag course, arriving at your downwind destination through a series of reaches . Letting out the mainsail more by loosening the sheet, or allowing the boom to rise by loosening the boom vang or the traveler, will not help when running down before the wind. Also futile for this problem are adjustments aiming to move the center of effort relative to the center of lateral resistance -- these only help for points of sail other than running down before .
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("running down before the wind")
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that situation by
running down before the wind by instead
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reaching
arriving at
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. Letting out the mainsail more by loosening the sheet, or allowing the boom to rise by loosening the boom vang or the traveler, will not help when running down before the wind. Also futile for this problem are adjustments aiming to move the center of effort relative to the center of lateral resistance -- these only help for points of sail other than running down before