Part II - Crew Control and Boat Handling
Build 27 · 20 September 2026 · not yet reviewed
6Upwind Performance Modes
Sections in this chapter
Close-hauled, the 49er has no single correct state; it has a band of steady states between a low, fast course and a high, slow one, and the crew chooses a point in that band to suit the moment. This chapter treats that choice as a set of named modes, each defined by what it gives up. Section 6.1 defines fast mode, pointing mode and recovery mode by their trades, explains how trim, heel and steering set each one, and states when each is used tactically. Section 6.5 turns to the hydrodynamic side of the same problem: leeway is the angle of attack that lets the daggerboard work, and rudder angle is the gauge that shows whether rig and foils are in balance, so both are readings the crew interprets rather than faults to be cured. Section 6.6 applies recovery mode to the three situations in which a 49er loses flow most often, the exit from a tack, a wave impact and another boat's disturbed air, and gives the acceleration sequence common to all of them.
6.1Fast mode, pointing mode, and recovery mode
A mode is a deliberate departure from the , bought with a defined trade: fast mode trades height for speed, pointing mode trades speed for height, and recovery mode trades both for the re-establishment of flow over sails and foils. The optimum is the reference, not a mode; either departure costs VMG, as Ingham states for the asymmetric S28, and the arithmetic is the same close-hauled. Staying away is expensive: in the 49erFX of race time on skills, first-beat VMG carried a coefficient of -2.0, "almost ten times that of any other skill" S37. A mode is a short loan against VMG, repaid by a gain the crew names before taking it.
The mechanism is the direction of the sail force, which and drag along it S19. Steering higher closes the apparent-wind angle and rotates the lift vector so that more of it becomes side force and less becomes drive; speed falls, and the boat climbs the ladder rung only if the daggerboard is loaded enough to turn the side force into height rather than leeway. Steering lower rotates the vector forward and speed builds; as it builds "the apparent wind speed increases and the apparent wind angle decreases, moving further forward" S26, so a fast mode partly repays itself, because the stronger apparent wind adds drive and the higher speed reduces leeway.
Each mode is set through Gladstone's , angle of attack, depth and twist S20. Fast mode carries more depth, because "More depth creates more power and better acceleration" S20, a leech twisted open at the top, eased sheets and a heading a few degrees below the optimum; it departs from the class baseline, whose published references are the jib track pins in the innermost holes and the jib sheet in the middle hole up to about 12 knots in flat water S13, by the amounts the crew has logged, crew value. Pointing mode removes twist, since "decreasing twist adds power" S20, trims the mainsheet until the top batten is parallel to the boom S34, sheets the jib harder and inboard, and holds the boat flat, within the skiff coaching band in which "+/- 5 degrees is acceptable" S36; it is used "sparingly when boat is up to speed in ideal conditions" W1. Recovery mode is "Bear off and ease main slightly" W1, draft forward and leech open until speed returns.
The tactical rule is "Foot in a lift and point if you're forced to sail in a header" W2: footing in a lift increases separation from boats to windward, pointing in a header reduces it, and each limits the loss when the shift arrives W2. Pointing mode also holds a lane off the line; fast mode reaches a gust carrying 30 to 40 percent extra wind speed S50 and clears a bow before a tack. The test for a fast mode is Bithell's test for the high road in conditions, where the faster angle can mean "sailing extra distance for not much extra speed gain" S29: the crew names the gain and the distance over which the mode runs, and returns to the optimum when that is spent.
6.5Leeway, rudder angle, and directional stability
Leeway is the angle of attack of the daggerboard and rudder, not a fault. The foils generate side force only when the boat moves somewhat sideways S19, and most racing boats sail upwind in medium breeze with 3 to 5 degrees of leeway S23. Since the foils are "much more effective at generating lift" when moving through the water S35, the leeway angle for a given side force falls as speed rises. Excess leeway has a short list of causes: low speed, because "As the boat slows, there is less flow over the foils, and therefore less lift" W3; heel, because "The foils are less effective when they are not vertical in the water" W3; and an over-trimmed mainsail, which "generates more side force increasing leeway" W3.
Rudder angle measures the moment imbalance between the sail plan's and the foils' centre of lateral resistance. "creates weather helm", and North Sails sets the target at 3 to 5 degrees of weather helm in moderate conditions S32; within that band the rudder is a lifting foil working with the daggerboard, so a little weather helm adds height; beyond it the rudder is a brake, adding to an that is already about 10 percent of the total near S19. Heel changes the reading at once: leeward heel moves the centre of effort outboard of the hull's line of resistance and creates a only the rudder can cancel, the second reason behind the skiff standard "Flat is FLAT" S36. Rig settings change it more slowly: " which will reduce power to the rig" S12.
, the tendency to hold a heading with the rudder near neutral, depends mainly on daggerboard area and crew weight placement. The Ovington manual wants maximum board area when looking for pressure and, once overpowered, tells the crew to "progressively lift the board" W4; a raised board makes less side force per degree of leeway, so leeway rises, but the heeling moment from the foil falls, and the crew's board heights per wind band are crew value. Low trapezing and keeps the sail plan upright S25, which keeps the foils vertical and the centre of effort steady, leaving the rudder only small corrections.
On the water leeway is read from the wake, where "the windward side wake is at a greater angle to the boat than the leeward side wake" W3, and afterwards from the difference between compass heading and logged track W3, within the limits places on compasses and tracking equipment S3. Rudder angle is read from tiller load. Rudder angle above the crew's reference crew value with the boat flat is a rig-balance problem, answered with rake, mast bend or sheet tension; with the boat heeled it is a heel problem, answered with trapeze height and sheet ease first. Leeway above the normal band with the rudder near reference is a speed problem, answered with fast or recovery mode and never with more height, because pinching a slow boat raises the leeway angle until the daggerboard stalls.
6.6Acceleration after tacks, waves, and disturbed air
Acceleration is the re-establishment of over sails and foils after a loss of speed, and the sequence is the same whatever the cause: bear away, build flow, sheet in as the apparent wind comes forward. Apparent wind is the of true wind and boat course S19. At low speed the apparent wind is lighter and further aft, so a sail sheeted for full speed is over-trimmed, its angle of attack too large and its leeward flow separated. As the boat gathers way "the apparent wind speed increases and the apparent wind angle decreases, moving further forward" S26, and the sheet follows it inboard. The foils obey the same order: with less flow there is less lift W3, so pointing before speed exists converts height into leeway.
Recovery mode therefore begins with depth and twist, which do not depend on speed. "More depth creates more power and better acceleration" S20; outhaul and vang sit a fraction softer than the wind warrants, the cunningham holds the draft forward S34, and the leech is open so the head does not stall first. SailZing prescribes this gear "at the start, after a tack, in waves, or any time boat is slower than it should be for the conditions" W1. The boat is held flat with weight forward: moving aft in a tack "is like " W4. Trim is restored in steps, each triggered by a rise in apparent wind, not by a count.
After a tack the loss has been chosen, so the sequence is rehearsed. The Ovington manual gives "Ease some jib sheet, about 100mm in normal conditions, 200mm in fresh to frightening, keep the main in as the tack is commenced and ease it as the tack is completed" W4. The exit is deliberately low of close-hauled, the eased jib pulls the bow through the last of the turn without rudder, both sailors reach the wire before the main is loaded, and the helm luffs to the chosen mode only as the crew sheets the jib home and the leech telltales fly. Manoeuvring efficiency matters "more prominently in strong wind conditions" S30. The standard is target speed crew value within crew value boatlengths of the exit.
A wave impact and disturbed air call the same sequence with different triggers. A wave that stops the bow also and disturbs the flow over the foils W3; the helm bears away a few degrees before the next crest, the crew eases a fraction, and both re-trim as speed returns. When leftover waves run at an angle to a new breeze, each tack needs its own mode S77. Upwind the rule is to tack away from a boat on or to weather of the bow "within 6 to 10 boatlengths (the greater distance is in lighter conditions)" S56. If the crew holds, for a layline, a shift or a lane, the boat is footed for pressure at once, because inside a shadow the wind is lighter, turbulent and bent toward the bow, and pointing mode is unavailable.