Talk:Genoa (sail)

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A genoa (pronounced like the city, or as jenny) is a type of large jib-sail used on bermuda rigged craft, commonly the single-masted sloop and twin-masted yawl, less frequently on a ketch. Its large surface area increases the speed of the craft; however in high wind conditions a smaller storm jib is usually substituted.

The term genoa is often used somewhat interchangeably with jib, but technically there is a clear delineation. A jib is only as large as the foretriangle, which is the triangular area formed by the mast, deck or bowsprit, and forestay. A genoa is larger, with the leech going past the mast and overlapping the mainsail. Genoas are categorized by the percentage of overlap. This is calculated by looking at the distance along a perpendicular line from the luff of the genoa to the clew, called the LP (for "luff perpendicular"). A 150% genoa would have an LP 50% larger than the foretriangle length. Sail racing classes often specify a limit to genoa size. On International Offshore Rule boats, different classes of genoa have 150%, 130%, and 98% overlap, and so on. Under Performance Handicap Racing Fleet rules most boats are allowed 155% genoas without a penalty.

Genoas do add more sail area to a craft, but at the expense of more difficult handling. It is harder to tack a genoa than a jib, since the overlapping area can become tangled with the mast unless carefully tended during the tack. Genoas are very popular in some racing classes, since they count only the foretriangle area when calculating foresail size; a genoa allows a significant increase in actual sail area within the calculated sail area. In boats where sail restrictions are not applicable, genoas of 200% overlap can be found, although those over 150% are not often seen, since the additional area is shadowed by the mainsail and generates diminishing returns in terms of power per actual sail area.

The gennaker is a fairly new type of sail, and is a hybrid between a genoa and an asymmetrical spinnaker. Gennakers are even larger than genoas (200% overlaps are not uncommon). They have a much greater camber than a genoa, for generating larger amounts of lift when broad reaching and running, but the large camber results in poor performance when close hauled, making the gennaker a downwind only sail. Spinnakers, on the other hand, are strictly for running, and will collapse if used to reach.

Comment:

The phrase in the article above introducing the luff perpendicular is not clear to me.

"This is calculated by looking at the distance along a perpendicular line from the luff of the genoa to the clew, called the LP (for "luff perpendicular")."

A line is a distance between two points. The clew is a point, but the luff is a line. One must define the point on the luff to use.

The word "perpendicular" describes a relation of 90°. A line cannot be described as a perpendicular in isolation. A perpendicular line is necessarily in relation (90°) to something else which has at least two dimensions (a line or a plane). Only once the relation has been described can one refer to the perpendicular alone.

If the editor of this article understands the LP, he can easily make the necessary clarifications. If not, I would be happy to research this point and do it myself. I can't do it right now because I'm in Paris and my yachting books are in Saint-Tropez.

I happened to read the article because I was hoping to learn the history of the genoa. I'm a specialist of racing sailboats of the class called the 6 metre International Rule. In our oral tradition, the genoa was invented by one of our illustrious owners of the 1920's, the Swedish diplomat Sven Salèn. He was apparently posted to Genoa when he developed it.

I was looking for information on the genoese contribution to this invention. The Web site of the Seawanhaka Corinthian Yacht Club of Oyster Bay, Long Island U.S.A. says that the first genoa was introduced to the U.S. during the 6 metre Scandinavian Gold Cup competition of 1927. It says that it was introduced by "an Italian boat". During this competition, Sven Salèn represented Sweden on May Be and there was also an Italian entry named Mati (now Fissa).

If anyone was in a position to introduce the genoa to the U.S. in 1927, it would have been Sven Salèn on his Swedish boat. Perhaps, Mati had also adopted the genoa. Perhaps the Seawanhaka confused Salèn's consular posting at Genoa with his Swedish boat - or perhaps they automatically ascribed this genoese novelty to the genoese boat Mati.

I'll ask them if they can sort it out.

Basil Carmody basil@carmody.ws Paris & Saint-Tropez, France

I deleted the section that said the spinnaker was strictly for a run. Spinnakers can be used on reaches; if the pole is pulled far enough forward you can practically sail a beam reach.