Tack (sailing)
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Tack is a term used in sailing that has different meanings in different contexts.
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[edit] Sail
The tack is the lower corner of the sail's leading edge. On a sloop rigged sailboat, the mainsail tack is connected to the mast and the boom at the gooseneck. On the same boat, a foresail tack is clipped to the deck and forestay.
[edit] Maneuver
A tack or coming about is the maneuver by which a sailing boat or yacht turns its bow through the wind so that the wind changes from one side to the other. During a tack, a vessel's tack or (position in accordance to the wind) will change. For example, if a vessel is sailing on a starboard tack (the wind is hitting the starboard side) and tacks, they will end up on a port tack now that the bow has crossed through the direction of the wind and the wind is now hitting the port side. *see image. This is in distinction to a jibe (also known as wear or wearing during the age of sail), which is turning the stern of the boat through the wind.
Tacking is also incorrectly referred to as beating.
[edit] Beating
It is the general process by which a ship moves on a zig-zag course towards the direction that the wind is coming from. As no sailing vessel can move directly against the wind—while necessity may dictate that it should go into just that direction—beating allows the vessel to advance against the wind direction. Commonly the closest angle a yacht can sail to the wind is around 35 to 45 degrees, this position is known as close hauled
This is done by turning as close into the wind as practicable and then, after a time of sailing, reversing tack to gain back the sideways displacement that occurred during the first tack. Depending on how much sideways space there is (from a small navigable channel to a full ocean) tacks may be minutes or even days in between.[citation needed]
Historically, sailing vessels were very bad at sailing against the wind, especially square-rigged ships. This has steadily improved, with modern yachts being able to almost—but not quite—move against the wind direction.[citation needed]
[edit] Procedure
Notify your crew that you are tacking. (you are doing this so they are aware of the boom switching sides and to watch their heads)
As a crew, you may hear one of many terms such as: Coming about, Helm's a-lee, Hard a-lee, or Lee Ho during the process
The next step as a skipper, is to push the tiller towards the sail or away from you (assuming you are facing your sail and the boom is away from you)
You will hear an intense racking/fluffing/banging noise of your sail (This is good) This means you are facing directly into the wind (essentially your sail is a flag) marking the half way point through your tack.
When the noise stops, your sail will calm down and begin to form a smooth curve again (this is good) This means you have completed your tacking process and now your vessel is on a different tack (port vs. starboard)
At this point you should still be facing your sail and the boom away from you. This means that you would have had to switch sides in your vessel as the boom switched sides during the tack. Timing, precision and comfort are all factors into form of tacking and are purely dependent on the sailors preference. However, there is a type of tack known as a roll tack which does have a uniform, "right" way of being completed.
Before tacking, it is a good practice to have a considerable amount of speed in order to complete the tack. If a vessel hasn't enough speed to complete a tack, the wind may overpower the boat's turn. The loud noise won't go away at this point and in most cases, your vessel will begin to go backwards as it has no power to fight back the wind which may push back your vessel. This event is most commonly known as "getting stuck in irons"
An auto tack is a modern term referring to when a sailboat turns its bow through the wind by accident. This usually occurs in one of two circumstances: either when a steady hand is not kept on the tiller or steering wheel, or when a sudden and large wind shift occurs, such as in a narrow river or lake, causing the wind to come from the other side of the sail even though the boat has not changed course. Auto tacks are more likely to occur when a sail boat is close hauled but may happen on any point of sail.
Beating to windward refers to the process of beating a course upwind, and generally implies (but does not require) actually coming about.
When used without a modifier, the term "tacking" is always synonymous with "coming about"; however, one can also "tack downwind"; i.e., change tack by jibing rather than coming about. The reason racing sailboats do this is that most modern sailboats (especially larger boats with spinnakers and a variety of staysails) sail substantially faster on a broad reach than running dead before the wind. The extra speed gained by zigzagging downwind more than makes up for the extra distance that must be covered. Cruising boats also often tack downwind when the swells are also coming from dead astern (i.e., there is a "following sea"), because of the more stable motion of the hull.
[edit] Position
As a noun, tack describes the position of a sailboat with respect to the wind and is primarily important as relates to the rules of the road that define which boat has right-of-way when two boats converge. Informally a sailboat's "Tack" is defined by the windward side of the boat at any particular moment-- if the port (or left) side is "to windward", the sailboat is said to be on the "port tack". The "windward" side is not always the side where the wind is coming from however; a boat that is "running" with the wind has the wind coming over its stern and a boat that is in the act of tacking passes through a zone where the wind is coming from directly ahead. For the purposes of right of way rules we therefore define a sailboat's windward side, and therefore the "tack" the boat is on, as being the side opposite the boom; or in the case of a sailboat with multiple masts, the side opposite the mainsail boom. In most cases a sailing vessel on a port tack must give way to another sailing vessel on starboard tack by both the rules of the road and racing rules. Exceptions to this rule occur very occasionally, such as when the port tack boat does not have sea-room to tack or manouver out of the way.
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