Consequently I have put together some brief notes specific to Dart 15 racing, kept as basic and fundamental as possible, which I hope will enable you to sharpen your act up and enjoy some close competition nearer the front from now on .
A Dart 15 is no different to any other boat in learning how to sail it to it's optimum performance, and is in fact one of the easiest boats to sail, being fundamentally more stable than a monohull, and having remarkably few ropes to adjust to extract maximum performance. Like any other boat though, it is difficult to race consistently well, and it takes 100% commitment from you for 100% of the race to achieve the desired results. The well- oiled phrase - YOU HAVE TO LEARN TO WALK BEFORE YOU CAN RUN can be applied to sailing, for you must learn to sail well before you can race well, and there is a vast difference between the two.
SETTING THE BOAT UP:
You should make the appropriate adjustments before racing, based on the probable wind-speed and the sailing water (e.g.- flat inland / rough chop at sea etc.). The reality is that a lot of us do not bother changing anything for regular club racing, but to ensure your boat is set to it's optimum performance FOR YOU, the following considerations should be made:-
This is always a difficult one to get right, as the wind strength is rarely constant for the length of an average race, so a good compromise is what you should be seeking, and the sail should be set up with regard to the weight of the helm and the general wind speed. I see no point in trying to quote statistics here, because everybody's physical abilities are different, as are their sailing skills and styles. If you look around your fleet, you will almost certainly notice that everyone sails their boat in a slightly different way - how they sit on the boat - how far out they can get when it blows - how quickly they can react to gusts - but possibly the most important factor, believe it or not, is their psychological commitment in trying to win a race. So you can see that the variables are considerable, but all that aside, the basic guidelines are as follows :-
For very light winds (7 knots or less) and strong winds (20 Knots plus), batten tension should be zero, and should really be seen as sail tension , the idea being to keep the sail as flat as possible . In very light airs , the wind will not follow a pronounced curve in the sail, and it will stall. In heavy winds, the average helm (weight-wise) will not be able to handle all the available power from a fully tensioned rig. In light winds ,the sail will still take up a curved shape, but will not be excessive, and the battens will reverse their curvature more easily when tacking. In between that range i.e. 8-20 knots, tension the sail approximately 1/2" more on each batten (less on the top one) so that it induces a permanent curve. This will then generate full power which should be perfectly manageable in this wind strength.
This is again something which is rarely altered during club racing, but there are gains to be made, which may compensate for weaknesses you may have in other areas.
For 15 knots or less on flat water, there should be very little mast rake aft, but for windier conditions, and also sailing in choppy seas, move the shroud pins down one hole to increase mast rake, and apply more rig tension by subsequently tightening the forestay. In most cases, adjustment by just one hole is all that is necessary. A fairly upright mast will give quite acceptable pointing ability in moderate winds on flat water, with definite gains to be made off-wind, but will tend to nose-dive more off- wind above 18 knots, necessitating the helm to be 13 stones plus, or sit on the rudder to counteract this. Raking the mast back one hole will improve pointing ability in most wind strengths, and also help to drive the boat to windward through choppy seas. It will also handle better off-wind in strong winds and reduce the tendency to nose-dive.
This is adjusted by tensioning the forestay , which in general should be kept fairly tight for most wind strengths. For clarity, I would break this down into 3 conditions:-
8 knots or less-The rig can be fairly slack , i.e. just tension the forestay enough to keep the shrouds straight.
8-18 knots-Tighten the forestay another inch to put some tension into the shrouds. This will also help to stiffen up the whole boat and prevent the hulls from twisting relative to each other.
18 knots-survival conditions-Tighten the forestay another inch to the point where it is difficult to deflect the shrouds inwards by pushing with your finger ends.
The disadvantages of sailing with a slack rig are that in addition to allowing more fore and aft movement, it also means that when beating, the mast will lean more to leeward, and bend off a lot more at the top, resulting in a very slack leeward shroud as the mast also curves to windward BELOW the shroud attachment point. Given that in a decent breeze, the windward hull should be almost clear of the water, the mast is already angled away from the wind, and any further bending away will not help upwind boat speed at all. This additional bending also means that the sail will not set correctly on the mast.
So it's a case of swings and roundabouts really. There are small gains to be made in certain conditions, but I am of the opinion that it will only pay to have a slack rig in under 8 knots of wind, when both hulls will remain in the water, and the forces trying to bend the mast are minimal. In these conditions, you will automatically induce more mast rake when beating by pulling in the mainsheet 'block-to-block', and conversely off-wind, the mast can go forward more at the top when the traveller and mainsheet are let out fully.
To keep it simple, there is not much to remember here.
BEATING - In winds up to 18 knots, tension the downhaul to take all the horizontal creases out of the sail, and no more. Above this wind strength put as much tension on as you can, which will flatten and de-power the sail, and bring the centre of curvature forward, all improving pointing ability.
REACHING - Ease the downhaul just to the point where horizontal creases would start to appear.
BROAD REACHING - Let the downhaul off completely.
RUNNING - Don't! You can sail broader than most cat's, even a Dart 18, but point it dead downwind and that is exactly what you will be. The sail will bend round the leeward shroud in an S- shape, boat-speed will fall off noticeably, and the boat will feel lifeless and unstable, and may gybe itself without warning.
One general comment about the downhaul. In strong winds, just forget about adjustment altogether and leave it on all the time. Off-wind you may not have the weight or the courage to risk going forward to the mast to let it off, and end up nose-diving or even pitch-poling as a result.
Basically this should be adjusted in and out with the sail, so that it remains directly below the clew except when the sail is fully out on a broad reach. This will then ensure full power is extracted all the time by keeping the leach vertical, preventing it from twisting off at the top and thereby losing power.
WHERE TO SIT:
If you sit right up to the windward shroud on all points of sailing, you won't go far wrong. However, when beating, you should balance the boat fore and aft by looking at the inside front waterline on the leeward hull, and try to keep it just below the surface (in other words slightly nose-down). The other thing to remember is to firstly sit inboard to encourage the windward hull to lift just clear of the water, but no more, and you should try to maintain this state of balance by subsequently sliding in and out as the wind dictates. In strong winds however, or choppy seas, you will need to sit further back and further out to stop the bow burying and slowing the boat, thus helping it to sail over the waves rather than through them.
Just to emphasise one final point I made earlier about PSYCHOLOGICAL COMMITMENT, it really does make a difference. It is no good just pulling in the sail, sitting there like a passenger, and expecting the boat to do the rest, and blaming the weather or bad boat set-up when you come in last. If you really want to win a race, you have to put all your plans, calculations, cunning, rule knowledge, wind information, boat handling skills and total determination into action for 100 percent of the race to stand a chance of being up there in the front row.
Well there you have it. I hope I have managed to keep it basic enough without insulting your intelligence or over- complicating it with technicalities. The rest is up to you , but remember - PRACTICE MAKES PERFECT !
Th-th-th-th that's all folks !
Dartful Codger II