Hiking (sailing)

In sailing, hiking (stacking or stacking out in New Zealand) is the action of moving the crew's body weight as far to windward (upwind) as possible, in order to decrease the extent the boat heels (leans away from the wind). By moving the crew's weight to windward, the moment of that force around the boat's center of buoyancy is increased. This opposes the heeling moment of the wind pushing sideways against the boat's sails. It is usually done by leaning over the edge of the boat as it heels. Some boats are fitted with equipment such as hiking straps (or toe straps) and trapezes to make hiking more effective.

Hiking is most integral to catamaran and dinghy sailing, where the lightweight boat can be easily capsized or turtled by the wind unless the sailor counteracts the wind's pressure by hiking, or eases the sails to reduce it. The heavy keel on larger keelboats means that it is rare to capsize them due to wind alone, but keelboat racers will still hike to prevent unnecessary heeling, or leaning sideways to leeward, because the more vertical in the water the keel is, the more effective it is at keeping the boat moving in a forward direction and preventing it from drifting to leeward, slowing the boat due to drag, and potentially increasing the distance the boat must sail when beating. Improper heel creates a tendency for the boat to turn off course, necessitating a correction with the rudder, which also increases drag. Sails use wind most efficiently when they are at a proper heel, another reason for controlling heel.

Many boats, especially dinghies, have equipment that facilitates effective hiking. Hiking straps (toe straps) made from rope or webbing hold the sailor's feet down, allowing them to lean back over the gunwale of the boat while sitting facing in. These simple devices are almost universal on dinghies that do not have more complex hiking systems. Some sailors wear special shorts fitted with pads or stiff battens to help them hike more effectively and without tiring.

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Wikipedia