The S2 7.9, originally called the Grand Slam 7.9, is an American

sailboat A sailboat or sailing boat is a boat propelled partly or entirely by sails and is smaller than a sailing ship. Distinctions in what constitutes a sailing boat and ship vary by region and maritime culture. Types Although sailboat terminology ...

that was designed by Graham & Schlageter as a

one-design One-design racing is a racing method which may be adopted in sports using complex equipment, whereby all vehicles have identical or very similar designs or models, avoiding the need for a Handicapping, handicap system. Motorsport One-make racing ...

and

Midget Ocean Racing Club The Midget Ocean Racing Club (MORC) is an American association based in Severna Park, Maryland, that promotes and organizes ocean Sailing (sport), racing for small sailboats under a handicapping rule. History Founded in 1954, the club was for ...

(MORC) racer-

cruiser A cruiser is a type of warship. Modern cruisers are generally the largest ships in a fleet after aircraft carriers and amphibious assault ships, and can usually perform several operational roles from search-and-destroy to ocean escort to sea ...

and first built in 1979. The designation indicates the

length overall Length overall (LOA, o/a, o.a. or oa) is the maximum length of a vessel's hull measured parallel to the waterline. This length is important while docking the ship. It is the most commonly used way of expressing the size of a ship, and is also ...

in meters.

Production

The design was built by S2 Yachts in

Holland, Michigan Holland is a city in Ottawa County, Michigan, Ottawa and Allegan County, Michigan, Allegan counties in the U.S. state of Michigan. Located in the West Michigan, western region of the Lower Peninsula of Michigan, Lower Peninsula, the city is si ...

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

, but it is now out of production. In 1989 the company was asked by the ''S2 7.9 Class Association'' if the design could be put back into limited production and the company agreed, but with a minimum order of ten boats for production to be restarted. The association and the S2 dealership network tried to come up with the ten orders, but was unable to do so at that time. ''Practical Sailor'' magazine termed this incident, "an unfortunate commentary on the sailboat industry" and noted it marked the end of sailboat production for the company. A few more boats were built by S2's Tiara division in 1990 and 1994.

Design

The S2 7.9 is a recreational

keelboat A keelboat is a riverine cargo-capable working boat, or a small- to mid-sized recreational sailing yacht. The boats in the first category have shallow structural keels, and are nearly flat-bottomed and often used leeboards if forced in open w ...

, built predominantly of hand laid

fiberglass Fiberglass (American English) or fibreglass (English in the Commonwealth of Nations, Commonwealth English) is a common type of fibre-reinforced plastic, fiber-reinforced plastic using glass fiber. The fibers may be randomly arranged, flattened i ...

with an end-grain

balsa ''Ochroma pyramidale'', commonly known as balsa, is a large, fast-growing tree native to the Americas. It is the sole member of the genus ''Ochroma'', and is classified in the subfamily Bombacoideae of the mallow family Malvaceae. The tree is fa ...

core, with wood trim. All models have a

raked stem The stem is the most forward part of a boat or ship's bow and is an extension of the keel itself. It is often found on wooden boats or ships, but not exclusively. Description The stem is the curved edge stretching from the keel below, up to ...

, a plumb transom and a transom-hung, pivoting

rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, airship, or other vehicle that moves through a fluid medium (usually air or water). On an airplane, the rudder is used primarily to counter adverse yaw ...

controlled by a

tiller A tiller or till is a lever used to steer a vehicle. The mechanism is primarily used in watercraft, where it is attached to an outboard motor, rudder post, rudder post or stock to provide leverage in the form of torque for the helmsman to turn ...

. The boat is normally fitted with a small

outboard motor An outboard motor is a propulsion system for boats, consisting of a self-contained unit that includes engine, gearbox and propeller or jet drive, designed to be affixed to the outside of the transom. They are the most common motorised method ...

for docking and maneuvering. A German

BMW Bayerische Motoren Werke AG, trading as BMW Group (commonly abbreviated to BMW (), sometimes anglicised as Bavarian Motor Works), is a German multinational manufacturer of vehicles and motorcycles headquartered in Munich, Bavaria, Germany. Th ...

inboard

diesel engine The diesel engine, named after the German engineer Rudolf Diesel, is an internal combustion engine in which Combustion, ignition of diesel fuel is caused by the elevated temperature of the air in the cylinder due to Mechanics, mechanical Compr ...

of was a factory option plus a few were factory-equipped with

Yanmar is a Japanese diesel engine, heavy machinery and agricultural machinery manufacturer founded in Osaka, Japan, in 1912. Yanmar manufactures and sells engines used in a wide range of applications, including seagoing vessels, pleasure boats, cons ...

diesels. The design has sleeping accommodation for four people, with a double

"V"-berth A sleeping berth is a bed or sleeping accommodation on vehicles. Space accommodations have contributed to certain common design elements of berths. Beds in boats or ships While beds on large ships are little different from those on shore, ...

in the bow cabin, and two straight settee

quarter berth A sleeping berth is a bed or sleeping accommodation on vehicles. Space accommodations have contributed to certain common design elements of berths. Beds in boats or ships While beds on large ships are little different from those on shore, ...

s in the main cabin. The

galley A galley is a type of ship optimised for propulsion by oars. Galleys were historically used for naval warfare, warfare, Maritime transport, trade, and piracy mostly in the seas surrounding Europe. It developed in the Mediterranean world during ...

is located on the port side just forward of the

companionway In the architecture of a ship, a companion or companionway is a raised and windowed hatchway in the ship's deck, with a ladder leading below and the hooded entrance-hatch to the main cabins. A companionway may be secured by doors or, commonly i ...

ladder. The galley is on the port side, is "minimal" and is equipped with an

icebox An icebox (also called a cold closet) is a compact non-mechanical refrigerator which was a common early-twentieth-century kitchen appliance before the development of safely powered refrigeration devices. Before the development of electric refrig ...

and a sink, but no stove. The

head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple ani ...

is located next to the keel trunk on the starboard side. Cabin headroom is . For sailing the design is equipped with a 155%

genoa Genoa ( ; ; ) is a city in and the capital of the Italian region of Liguria, and the sixth-largest city in Italy. As of 2025, 563,947 people live within the city's administrative limits. While its metropolitan city has 818,651 inhabitan ...

or a 105%

jib A jib is a triangular sail that sets ahead of the foremast of a sailing vessel. Its forward corner (tack) is fixed to the bowsprit, to the bows, or to the deck between the bowsprit and the foremost mast. Jibs and spinnakers are the two main ty ...

. For sailing downwind the design may be equipped with a symmetrical

spinnaker A spinnaker is a sail designed specifically for sailing off the wind on courses between a Point of sail#Reaching, reach (wind at 90° to the course) to Point of sail#Running downwind, downwind (course in the same direction as the wind). Spinna ...

. The design has a

PHRF Performance Handicap Racing Fleet (PHRF) is a handicapping system used for yacht racing in North America. It allows dissimilar classes of sailboats to be raced against each other. The aim is to cancel out the inherent advantages and disadvantages ...

racing average handicap of 168 and a

hull speed Hull speed or displacement speed is the speed at which the wavelength of a vessel's bow wave is equal to the waterline length of the vessel. As boat speed increases from rest, the wavelength of the bow wave increases, and usually its crest-to- ...

of . With a beam of the boat is not legally trailerable in most North American jurisdictions.

Variants

;S2 7.9 FK :This fixed keel model, with a

masthead sloop A masthead rig on a sailing vessel consists of a forestay and backstay both attached at the top of the mast. The Bermuda rig can be split into two groups: the masthead rig and the fractional rig. The masthead rig has larger and more headsails, a ...

rig, was introduced in 1979 and produced until 1986, but only 17 boats were built. It displaces and carries of ballast. The boat has a draft of with the standard keel. ;S2 7.9 :This lifting

daggerboard A daggerboard is a retractable centreboard used by various sailing craft. While other types of centreboard may pivot to retract, a daggerboard slides in a casing. The shape of the daggerboard converts the forward motion into a windward lift, co ...

keel model, with a fractional sloop rig, was introduced in 1981, produced until 1986 and 545 boats were constructed. It displaces and carries of lead ballast. One third of the ballast is in the keel and the balance fiberglassed into the hull. The boat has a draft of with the lifting keel down and with the keel up.

Operational history

The design is supported by a class club, the ''S2 7.9 Class Association'', which organizes races including a national championship and also regulates the design to maintain its

status for racing. In a 2000 review Darrell Nicholson wrote in ''Practical Sailor'', "S2 did a good job of aiming the boat at a variety of sailors: racers, daysailors, and weekenders. For racers interested in a one-design boat, the class is not strong outside the Great Lakes. But for the sailor into handicap racing, the boat seems a good possibility. It’s definitely competitive in MORC and PHRF fleets. And unlike other high-performance boats its size—the Olson 25,

J/24 The J/24 is an international One-Design trailerable keelboat class built by J/Boats and defined by World Sailing. The J/24 was created to fulfill the diverse needs of recreational sailors such as cruising, one design racing, day sailing, and ...

Merit 25 The Merit 25 is an American trailerable sailboat that was designed by Paul Yates as a Midget Ocean Racing Club (MORC) racer and first built in 1978.Sherwood, Richard M.: ''A Field Guide to Sailboats of North America, Second Edition'', pages 1 ...

, Evelyn 26, or

Capri 25 The Capri 25 is an American trailerable sailboat that was designed by Frank Butler as a one design racer and first built in 1980.Sherwood, Richard M.: ''A Field Guide to Sailboats of North America, Second Edition'', pages 160-161. Houghton Mi ...

— the 7.9 is a boat you could stand sleeping aboard or taking on a rainy overnight race." Brook Berth wrote in ''Sailing Magazine'', "the S2 7.9 is a nicely designed, well-built one-design racer that can be cruised on short trips." Jack Hornor wrote in ''The SpinSheet'', "the S2 7.9 provides exhilarating sailing performance and has the added benefit of sufficient accommodations to make occasional weekend cruises or overnight races tolerable at least. " A ''Sailing World'' review called the boat an "eminently sailable family cruiser-racer."

References

{{S2 Yachts Keelboats 1970s sailboat type designs Sailing yachts Trailer sailers Sailboat type designs by Graham & Schlageter Sailboat types built by S2 Yachts

Production

Design

Variants

Operational history

See also

References