Downwind in light airs

OTTO STRANDVIG ON LIGhT WIND TEChNIquE

Winning in light air in a Finn requires both training and technique, but not least a strong elastic JC Strap. The ends of the elastic are attached to the middle of the boom and run through a block on the bow, making sure that the sailor has full control over the boom and does not have to wait for the wind to push the boom out. We recommend 12mm elastic that can only be pressed straight through the bow block and it must be so short that it can sit half-tight in the centreboard’s uphaul blocks. Remove the elastic when you are not sailing so that it does not become slack.

It is important that all lines run smoothly and that the boat works so that you do not mess with it during a race.

In the following, a number of factors that need to be taken into account will be reviewed. The goal is for the boat to sail itself, so that the boat is steered without rudder pressure and not as usual where you as the helmsman provide the direction with the rudder.

HOW DO YOU CONTROL?

When the boat is horizontal, the water flows symmetrically past the hull, but if the boat tilts just a few degrees, the flow becomes asymmetrical and the boat will turn. A good exercise to get a feel for this is to drop the tiller in light weather on flat water and steer the boat by moving your body from side to side.

When the boat steers itself it will be in balance and there is no resistance from the rudder. This means that the centre of effort of the sail is vertically above the centre of effort of the hull. The centre of effort of the sail is roughly located in the centre of the sail, so the dinghy must be heeled to the point where the two centres come over each other. At low speeds, the boat can be heeled further without compromising the boat’s ‘resistance’ through the water than when getting up to speed. In the Finn you can put a foot under the traveller or arrange yourself with a toe strap to make it happen.

The hull’s centre of effort is also located behind the sail’s centre of effort and the distance between the two determines how easy the boat is to turn. If you sit completely aft and thus move the hull’s centre of effort aft, the boat will be more directionally stable. If you sit on top of the centreboard, the boat will be very easy to turn, which you can use in a flat sea.

If the speed is below 4 knots, you no longer need the entire waterline and then you can consider moving to get the wide stern of the hull out of the water and thus reduce the wetted surface, which is one of the components that provides resistance.

If you work systematically with the above elements, you can reduce the hull’s resistance under different conditions and at the same time manoeuvre without using much force.

WHAT GIVES SPEED?

There are two components that can give speed: gravity and the sail.

We utilize gravity by sailing downwards as much as possible and at least not sailing upwards. To sail downwards requires waves and in light winds it will be flat water or swells.

Since we must not pump in light winds, we must have another tool and no one has better tools than our friends from the Laser class. Their technique is roughly that, with the centreboard almost completely down, turn up on the leading edge of the wave at the same time as they ‘trim’ the sail, ie de facto pumps, heel the boat into the wind, so it starts to bear away and at the same time release the sheet. They turn 40-50 degrees while the sheet runs out and when the boom is at about 90 degrees, the flow is reversed on the sail and the sailor gives a good jerk, which should coincide with the stern being lifted by a wave.

The Finn is heavier and less manoeuvrable than the Laser, but the technique works fine with a little adjustment. The most important thing is that the boat must under no circumstances sail sideways, so the centreboard must be well down. In fact, there is almost no resistance from the board, so you can experiment with letting it go completely down.

Hold the sheet directly from the boom and remember that trimming is not an extra pump when you are changing direction. The latter is not permitted under Rule 42.

HOW TO DO IT IN PRACTICE?

The sail must be trimmed downwards before rounding the top mark. If you guide the Cunningham, inhaul and outhaul through a nylon eye that is attached to a hole in the edge of the boat, then you can slacken all three lines with a snap just before you reach the top mark.

Ease the sheet and let the boat bear away itself by heeling into the wind. Adjust the vang so that the leach / the three upper battens flex and when it is in place, you can possibly raise the centreboard. Hold the sheet and adjust so that you feel the sail pull.

Adjust the various components until you are satisfied with the speed and then focus on the tactics. If there is current then establish a transit to support you in sailing a straight line ‘course over ground’ to the mark (unless you can get out of the current).

If there is a gust of wind, bear away and follow it. Head up when the gust is gone.

IF THERE ARE OTHER BOATS

Avoid clumps of boats as much as possible because the wind tends to move over larger groups of boats. Do not be stressed that there is a boat trying to cover you. Instead, try to find the edge of the cover, where the wind can have a slightly higher speed and can be turned 5-10 degrees. If it’s a really annoying sailor, try to create distance with a handful of roll gybes - when you are in a fight, it is okay to gybe more often than if you are alone, where Rule 42 sets an upper limit.

When you get to the gate, you must choose the favourable mark – as a starting point the mark that is closest to the top mark. Therefore, it is important to have the gate inspected before the start so that you have the geometry in place.

If there is a traffic jam at the gate mark you have chosen, then it can be an advantage to stop the boat at the three-boat line so you secure an inner lane so you do not get bad air on the first part of the upwind.

wind

flat water

waves 0-5 knots

Sit still, heel boat, sit completely still, sail by the leech, now sit still, boat must not sail sideways, sit still… Body weight on traveller, centreboard almost all way down, roll gybe when pressure disappears; if wave and wind directions are differing then try different angles and tacks of sailing

5-10 knots

Balance, clear air flow on all leeward telltales, adjust vang to support sailing long ‘S’ shapes Centreboard almost completely down, (head up + sheet in / release sheet and bear away / sail by the leech with the boom at 90 degrees). Repeat