Genoa (sail)

The genoa is a type of large jib or staysail that overlaps the main sail, sometimes eliminating it. It was originally referred to as an "overlapping jib" and later as a Genoa jib. It is used on single-masted sloops and twin-masted boats such as yawls and ketches. Its larger surface area increases the speed of the craft in light to moderate winds; in high wind conditions a smaller jib is usually substituted, and downwind a spinnaker may be used. The feature that distinguishes a genoa from a working jib is that the former extends past the mast, overlapping the mainsail when viewed from the side.

The term jib is the generic term for any of an assortment of headsails. The term genoa (or genny) refers to a type of jib that is larger than the 100% foretriangle, which is the triangular area formed by the point at which the stay intersects the mast, and deck or bowsprit, and the line where the mast intersects deck at the rail. Colloquially the term is sometimes used interchangeably with jib. A working jib is no larger than the 100% foretriangle. A genoa is larger, with the leech going past the mast and overlapping the mainsail. To maximize sail area, the foot of the sail is generally parallel and very close to the deck when close hauled.

Genoas are categorized by a percentage representing their area relative to the 100% foretriangle. Sail racing classes often specify a limit to genoa size. Genoas are classified by their size; a modern number 1 genoa would typically be approximately 155%, but historically number 1 genoas have been as large as 180%. Number 2 genoas are generally in the range of 125–140%. Working jibs are also defined by the same measure, typically 100% or less of the foretriangle. Under Performance Handicap Racing Fleet rules, most boats are allowed 155% genoas without a penalty.

Maximizing the sail area can cause more difficult handling. It may be harder to tack a genoa than a jib, since the overlapping area can become tangled with the shrouds and/or 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 180% overlap can be found, although those over 150% are not often seen, since the additional area is shadowed by the mainsail when close hauled and generates diminishing returns in terms of power per actual sail area.

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