Spinnaker
A spinnaker is a sail designed specifically for sailing off the wind on courses between a reach to downwind. Spinnakers are constructed of lightweight fabric, usually nylon, and are often brightly colored. They may be designed to perform best as either a reaching or a running spinnaker, by the shaping of the panels and seams. They are attached at only three points and said to be flown.
Etymology
Some dictionaries suggest that the origin of the word could be traced to the first boat to commonly fly a spinnaker, a yacht called Sphinx, mispronounced as Spinx. Sphinx first set her spinnaker in the Solent in 1865, and the first recorded use of the word was in 1866 in the August edition of Yachting Calendar and Review. In addition, the term may have been influenced by the spanker, originally a gaff rigged fore-and-aft sail.Another suggestion is that the idea for the sail was conceived in 1865 by William Gordon, owner of the racing yacht Niobe. He wanted to name the sail after his yacht but a crewman's comment, "Now there's a sail to make her spin" became "spin maker" which developed into the commonly accepted term spinnaker. Gordon was widely known in the yachting world of the time as "Spinnaker Gordon".
It has been pointed out, however, that the skippers of Thames sailing barges also used the term spinnaker for their jib staysails. Unlike the other, tanned sails of these boats, the spinnakers were usually white. It has thus been suggested that the term could be "connected with the obsolete word spoon, meaning to run before the wind." Early usage of the verb to spoon can be traced back to the 16th century; the change from spoon to spin in the term spindrift is attributed to a local Scottish pronunciation. According to Merriam Webster's dictionary, however, spindrift derives from a local Scottish pronunciation of speen, meaning "to drive before a strong wind."
According to Merriam-Webster's etymology, the origin of the word spinnaker is simply unknown.
Types
There are two main categories of spinnakers, symmetric and asymmetric depending on whether a plane of symmetry exists for that particular sail. Asymmetric spinnakers operate more like a jib, generating lift from the side, rather than the top like a symmetric spinnaker. This makes asymmetrics a better choice on reaching courses than symmetric spinnakers, which excel when running. While a fully equipped racing boat might have a number of spinnakers, both symmetric and asymmetric, to cover all courses and wind conditions, cruising boats almost always use an asymmetric, due to the broader application and easier handling afforded by the asymmetric.Symmetric
The symmetric one is the most classic type, running symmetrically alongside the boat controlled by lines known as a sheet and a guy running from the lower two corners of the sail. The windward line, or guy, is attached to the corner called the tack of the sail, and is stabilized by a spinnaker pole. The leeward line is called the sheet. It attaches to the clew of the spinnaker and is used to control the shape of the sail. The spinnaker pole must be moved in each gybe, and is quite difficult for beginners to use. However, it can be sailed in all downwind wind directions.Symmetric spinnakers when sailing across the wind develop most of their lift on the forward quarter, where the airflow remains attached. When correctly set for reaching, the leading edges of a symmetric spinnaker should be nearly parallel to the wind, so the flow of air over the leading edge remains attached. When reaching, the sail camber allows only some attached flow over the leeward side of the spinnaker. On running the spinnaker is angled for maximum drag, with the spinnaker pole at right angles to the apparent wind. The symmetric spinnaker also requires care when packing, since the three corners must be available on the top of the packing.
Parasailor
A Parasailor is a symmetrical spinnaker with a paraglider wing inserted into a gap in the sail approximately mid-way up. This feature makes the sail easier to keep inflated, but detracts from its performance. The sail may be flown on a spinnaker pole or with the tack attached to the bow of the boat.Asymmetric
s resembling large jibs and flown from spinnaker poles are not a new idea and date back to at least the 19th century. However, in the 1980s a new concept appeared, starting with the Sydney Harbour 18ft Skiff fleet.Since the 1960s, many faster sailing craft, starting with catamaran classes, have discovered that it is faster to sail downwind on a series of broad reaches with efficient airflow across the sail rather than directly downwind with the sails stalled. This technique had developed to the extent that in bar conversation at the end of one season Andrew Buckland observed that the 18s had sailed all season without pulling the spinnaker pole back from the forestay and that all the systems could be simplified by eliminating the pole and setting the spinnaker from a fixed bowsprit. The concept quickly evolved to a sail with a loose luff much more like a conventional spinnaker than the old jib-style asymmetric sails. Julian Bethwaite was the first to rig and sail a boat with one the next season, followed shortly by Andrew Buckland. The first modern offshore sailboats to incorporate a retractable bow sprit and an asymmetric spinnaker was the J/Boats J/105.
The concept has spread rapidly through the sailing world. The tack of the sail may be attached at the bow like a genoa but is frequently mounted on a bowsprit, often a retracting one. If the spinnaker is mounted to a special bowsprit, it is often possible to fly the spinnaker and the jib at the same time; if not, then the spinnaker will be shadowed by the jib, and the jib should be furled when the spinnaker is in use.
The asymmetric has two sheets, very much like a jib, but is not attached to the forestay along the length of the luff, but only at the corners. Unlike a symmetric spinnaker, the asymmetric does not require a spinnaker pole, since it is fixed to the bow or bowsprit. The asymmetric is very easy to gybe since it only requires releasing one sheet and pulling in the other one, passing the sail in front of the forestay. Asymmetrics are less suited to sailing directly downwind than spinnakers, and so instead the boat will often sail a zig-zag course downwind, gybing at the corners. An asymmetric spinnaker is particularly effective on fast planing dinghies as their speed generates an apparent wind on the bow allowing them to sail more directly downwind. It is also particularly useful in cruising yachts in the form of a cruising spinnaker or cruising chute, where the ease of handling is important.
Cruising
A cruising chute is a form of asymmetric spinnaker used by cruising yachts and designed for easy use when short-handed. Two sheets are used, with the tack line eased by a foot or so before gybing. Alternatively, only one sheet is used, with the sail snuffed before a gybe.Code Zero
A Code Zero is a light-weight sail that approaches the dimensions of a genoa jib, for light airs and points of sail up to a close reach. It may be launched furled on its own stay.Ratings
The following codes are used for both symmetric and asymmetric sails.- Code 1 is a light air reaching sail, where the apparent wind angles at low speeds has a significant effect to create angles of less than 90 degrees.
- Code 2 is a medium air running sail, used for apparent wind angles over 90 degrees.
- Code 3 is a medium air reaching sail, used for apparent wind angles near 90 degrees.
- Code 4 is a heavy air running sail, used in the heaviest winds normally expected.
- Code 5 is a heavy air reaching sail, used in the heaviest winds normally expected.
- Code 6 is a storm sail, for running in storm conditions.
Setting the sail
Symmetric
Typically the symmetric spinnaker is packed in its own bag, called a turtle, with the three corners on top for ready access. The clews are controlled by lines called sheets. The sheets are run in front of the forestay and lead to the back of the boat. The head is attached to the spinnaker halyard, which is used to raise the sail up the mast.Symmetric spinnakers have the windward clew secured to a spinnaker pole. The pole is attached to the mast and holds the windward edge of the sail in position. Lines that control the spinnaker pole are called guys or braces. The spinnaker pole may be allowed to raise and lower with the force of the wind, or it may have lines attached to it to raise and lower the angle of the pole. If these lines are used, they are generally set up before setting sail and left in place even when the spinnaker is stowed.
Since spinnakers are downwind sails, they are never tacked, they are only jibed. When jibing a symmetric, the pole is removed from one corner and attached to the opposite corner. This corner now becomes the windward corner. There are two ways this is done. Generally on smaller boats, an end-for-end jibe is accomplished by disconnecting the pole at the mast-end and connecting the mast end to the opposite side of the sail. The old sail end is disconnected and then attached to the mast. This prevents the pole from getting loose during the procedure and allows the use of only two control lines that alternate as sheet and guy. End-for-end jibing requires a pole with identical fittings at either end. Larger boats do a dip-pole gybe in which the pole remains attached to the mast and the outer end is lowered until it can clear the head-stay and is then raised back up on the other side of the boat to the proper height with the topping lift. The guys are adjusted as before to set the sail angle on the new course. Dip-pole jibing can use a pole with one mast end and one sail end.
Smaller boats tend to use only one line on each clew. The windward line that runs through the jaw of the spinnaker pole is referred to as the guy and the one on the free-flying corner is referred to as the sheet. During a jibe, these roles and thus the names are reversed. Larger boats may choose to use both a sheet and guy on each corner, with the guy being a heavier line. Having 2 sets of lines will makes the jibe easier as the kite is flown by the two sheets while the crew at the bow and at the mast are removing one guy from the pole and attaching it to the other with no tension on them.
Retrieving the spinnaker is a multi-step process, and the take-down depends on wind position. First, the windward corner is detached from the spinnaker pole and the guy is released. This step is referred to as blowing the guy. This allows the spinnaker to collapse into the shadow of the mainsail, where the foot is gathered by a crew member. The halyard is then lowered, and a crew member gathers the sail and stuffs it carefully into the turtle, corners out, and ready for the next deployment. There are, however many other ways to retrieve the spinnaker depending on the conditions and intent. It may or may not go into a turtle. It may be pulled back into the cockpit & then down below to be repacked for the next hoist or be pulled in a foredeck hatch and left free for the next hoist.