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Wind surfing

Situational awareness

In stationary water, the direction of the wind may be determined from the waves. Or one may use the sail.

Preparing the boat

While sailing, the fin under the center board should be down in the water. The aft fin/ skeg is always down.

Mechanics

The sail and the fin operate on the same principle as an airplane wing. Critical forces are lift and drag. The lift generated by the sail is at an angle to the orientation of the board defined by the relative orientation of the sail.

When both the fin and the sail are aligned, the component of the lift perpendicular to the board is negated to some extant by the opposite lift generated in the water by the fin. When the center of effort of the sail is forward or backward relative to the center fin, a turn results.

One cannot sail closer than 45 degrees into the wind.

Controls

The feet are almost always on the center-line. The back should always (mostly) face the wind.

Use body weight

The sail with the mast is very heavy. To lift the sail out of the water, one has to use the body weight. The body weight should balance the weight of the sail - if the sail is to one side of the board, one should lean slightly back to the other side.

Static positioning

Hold the mast with the sail facing windward, with feet on either side of the mast. One gets into this position upon lifting the sail from the water.

One can turn the board under the feet using baby steps in the feet while using the sail against the wind for resistance. Thus, one can turn the board and arrange to be on the board’s left or right side while sailing.

Sailing

Here, you hold the boom, with feet aft of the mast. To go straight, you align the center of effort on the line perpendicular to the center fin.

Turning

To turn windward, you move the sail relatively backward. To turn leeward, move the sail relatively forward. One needn’t remember this - one can experiment on the spot and turn where one needs to.

Dealing with gust

Just release the hand towards the aft, rather than be pulled with the sail and loose balance.

Gross Movements

Reaching: Travel perpendicular to the wind. Running: Travel windward. Working: travel leeward at an angle.