________________________________________________________________________ The Following Article Was Written in 1979 (mentioned because the class is still going strong) The S-Boat at 60 By Susan Buck A tribute to a one-design class whose original boats are still racing. What makes the Herreshoff S-Boat unique? It's the oldest one-design class still actively racing and sailing in its original boats, now in their 60th season. Out of the 95 built by Herreshoff, about 75 are still sailing. Forty of these are racing. The S- Class Association of Western Long Island Sound races the full YRA Mid-Sound Championship season, as well as pre- and post-season races; the Narragansett Bay Fleet does around-the-buoy racing and competes in team races with the Long Island Sound group; and a few boats in Buzzards Bay, MA. The rest are scattered among Mystic, Conn., (which is mainly interested in restoration), and in Chesapeake Bay, California, and Hawaii (Herreshoff built a fleet for the Pearl Harbor YC in 1928. These were eventually wrecked. The two boats now in Hawaii were built by the U.S. Navy). S-Boat owners make up a roster of the best-known yachting names of their time: Nathaniel F. Ayer, Paul Hammond (who was the ringleader in getting them designed), Charles Francis Adams, Philip J. Roosevelt, Theodore Roosevelt Jr., the brothers H.S. and J.S. Morgan, Ralph Ellis, Swede Whiton (who made his debut as a racing skipper in the S-Boat Tea Ticket), and, more recently, Bob Bavier, Warner Wilcox, Bob McCullough, Everett Pearson, Milton Ernstoff (he and his crew of S-Boat skippers won the 1964 Bermuda Race), Geoff Spranger and Halsey Herreshoff. There's also one non-yachting but crusty name--General George Patton, who owned Spinddrift from 1931-1935. His wife raced it with the Manchester YC at Marblehead, Mass. Patton is said never to have set foot in it. The look of the S-Boat under sail is pure Herreshoff--fine, almost elegantly refined, hard- driving and powerful. She builds up speed quickly; five knots close-hauled in a 10-knot breeze is common. In many ways, the S-Boat anticipated modern yacht design. The rig looks old-fashioned, with running backstays, a boom extending beyond the transom, and 426 sq. ft. of sail. But the high ratio of sail area to wetted surface, the short, deep, heavy keel (3,350 lb.), the slack bilges, the mast curvature, an advanced hull shape--particularly the cropped stern and spoon bow--are features much in tune with the present. In this 60th sailing season, it is appropriate to ask Captain Nat's grandson, Halsey Herreshoff, himself a designer and builder of yachts, and a former S-Boat owner (Coquina, the same name as one of Capt. Nat's favorite small boats), about the S-Boat. His remarks earlier this year: "I'm sure that capt. Nat wanted to make the s-boat both easily driven and powerful. They have the great big rigs to make them good for light air, yet they have a lot of keel and a hull shape to make them very stable in heavy air. They've worked out to be great for the strong southwest wind we get in Narragansett Bay and for Long Island Sound's relatively lighter air." Some speculation still exists that the original model length was 30 feet, with long overhangs. This theory has it that the waterline is relatively long--20 feet, six inches, in relation to the overall length of 27 feet, six inches. One story goes that the original sponsors--Paul Hammond and a group from Seawanhaka Corinthian YC--asked to have the overhangs cut off, and that Capt. Nat took his knife to the model, thus accounting for both the long waterline and the cropped bow and stern shape. Halsey Herreshoff dismisses this. "It was not G.g. Herreshoff's practice to have too much dialogue with the people for whom he designed boats. It wouldn't have been at all characteristic for anyone to tell him what to do. And if they had, he probably wouldn't have done it! And there is certainly no evidence of any revision on the design model of November, 1919. The only change was a slight ballast touch-up after the first 1920 season. Capt. Nat added slightly to the bottom of the keel, which made it a trifle deeper and begin a little more forward than originally." The short, deep, efficiently-shaped keel gives the S-Boat good stability and good lateral force in the water, without a particularly large wetted surface. Halsey considers this choice of keel for the S-Boat somewhat early for the time. "She was designed in an era when the underbodies of the boats were typically longer fore and aft, with much more area," he says. "In that way, as in many others, she was an advanced boat." If Halsey Herreshoff were to redesign the S-Boat today, what would he change? Says he: "I don't think I'd change a thing! The best thing you could do would be to leave it alone." At 60 years, you can't do better than that. More Praise for the S Class Can We Comprehend The S-Boat? by Julian H. Gibbs The Herreshoff S class is not the only one-design yacht racing class to have survived more than half a century, but it is apparently the only such class which provides high level competition in boats built to the original design. (The current variety of Star boat, for example, is far lighter than the original and carries a different rig.) The S class not only restricts itself to Captain Nat Herreshoff's original design of S boat but also uses exclusively the original boats themselves, i.e. the boats built to this design between 1919 and 1938. A large majority of the S boats that have survived hurricanes and other perils of the sea are still being actively raced. The loving care by long series of owners, which has been responsible for this, would seem to constitute the greatest testimonial ever given a racing sailboat. The mystique surrounding these boats, in the areas where they are known and raced, is enormous. It is based only in small part on the fact that the names of the original owners, who commissioned the design, constitute an essentially complete list of the best known (and wealthiest!) yachtmen of their time. It is based in somewhat larger measure on the fact that the S boat represents the culmination of the thinking over a long career of the greatest of all racing yacht designers with regard to one of his many outstandingly successful lines of yacht design. Primarily, however, this mystique is attributable to the design itself. Owners repeatedly observe that the S boat feels like a big boat but responds like a small one. Even more remarkably, these seemingly contradictory attributes are not obliterated by extreme conditions. To a degree missing in any other design known to this observer, the S boat is fun to sail in five knots and also in thirty-five. But the intent here is neither to offer a hymn of praise nor to try to convince those who are unfamiliar with the S boat that it merits one. Rather the intent is to inquire if, with the advantage of 50 years of hindsight, we can fathom the thing that Captain Nat obviously knew and understand the features in the S boat design which have been responsible for its success. This can be a dangerous business. Ten years ago many would have questioned the short, deep keel. The relatively slack bilges would have been condemned till recently. The cropped stern has been fashionable at certain times and unfashionable at others. Until Olin Stephens revived it with Intrepid, the type of bow manifest in the Herreshoff S boat was considered an eccentricity of its design. Today we appreciate more fully Herreshoff's concern for such matters as moments of inertia, aspect ratios, prismatic coefficients, and wetted surface areas. We wisely conclude that a keel of high aspect ratio not only provides the high lift-to-drag ratio which yields the optimum combination of resistances to leeway (high) and forward motion (low) but also provides a high righting moment and consequent ability to carry an enormous spread of sail (425 sq. ft.); the high ballast (3,300 lbs.) to displacement (5,750 lbs.) ratio (ca. 60%!) also contributes to the stiffness. We also appreciate today another feature of the short, deep, (4'9") keel. Like the short ends of the hull, it tends to concentrate weight amidships, reduce the moment of inertia, and, consequently, curtail the pitching tendency; nothing slows a boat to windward more effectively than uncontrolled pitching. All these things we understand and more. The relatively narrow beam (7'3" on a 27' 6" l.o.a. with 20' 6" l.w.l.) provides good performance to windward in a chop. This beam and the largely ballast-determined displacement dictate, in accordance with an appropriate prismatic coefficient, the somewhat slack bilges, which one also finds in 12-meters. All these matters are clear to us now, and we congratulate ourselves on catching up with Captain Nat. But have we? It is hardly comprehension that inhibits our current thought that the S Boat might be better with a fin keel and spade rudder! No, our inhibition stems more from an awareness of the follies of fashion of the last 50 years and the impression that fin keels and spade rudders, with or without skegs, may well go the way of inside ballast, excessively long overhangs, reverse sheer, long keels, etc. Each of the latter characteristics was a must at some time or other during the last 50 years, and a Bob Smith, writing in the same vein as that of his recent article about the Etchells 22, would , at the corresponding time, have described boats that lacked each of these characteristics as mere "harbor decorations". S boat sailors on the other hand, knowing that Nat Herreshoff himself tried and discarded fin keels and spade rudders (with and without skegs), are not inclined to go overboard for them. Perhaps Herreshoff simply didn't like the mechanical weakness involved with these or the tendencies to easy fouling. At any rate the S boat, with its rudder mounted on a keel located well aft and with its spinnaker pulling on a mast located well forward, presents no problems of downwind steering and has no need for a separately mounted spade rudder. It is this last feature which causes this observer to wonder if even today we fully comprehend the design of many Herreshoff's most successful boats. Indeed, is it not conceivable that the marvelous, but seemingly mysterious, sailing qualities of the S boat are to be attributed as much to the aft location of its short keel as to its other, now well recognized, design features, noted above? One would never locate the feathers (keel and rudder) of an arrow ahead of the arrowhead (center of buoyancy)! Thus a location well aft for the center of lateral resistance would seem desirable if the center of effort can be located correspondingly far aft (to balance the boat for windward sailing) and if the center of displacement (and hence of buoyancy) can be kept more nearly amidships. The last requirement necessitates a location of the lead ballast primarily in the forward part of the keel. This is desirable also for protection against grounding damage (lead is soft and absorbs shocks). It does, however, imply a somewhat higher location for the center of gravity of the lead (the upper edge of which is sloped). Thus a modest price is paid in speed potential in return for significant advantages in handling qualities; that this can be done is one of the principal advantages of the one-design concept. The keel-mounted rudder provides, of course, greater sensitivity, in the form of shorter turning radius, than would be provided by a spade rudder mounted farther aft. Of perhaps even greater importance for the esthetics of windward sailing is the fact that a boat with a keel- mounted rudder performs best when tuned for a slight weather helm (trim tab effect). Boats with spade rudders require absolutely neutral helms for best performance. How many skippers really prefer a dead stick? The general plan of the rig follows the requirements of the hull form. When close-hauled the large mainsail and small jib provide a center of effort which is appropriately far aft for fine balance. Contrariwise, when eased off for a run, the mainsail (and spinnaker) pull on a mast located well forward. The fact that the large mainsail allows a relatively small spinnaker to be used also contributes to stable running conditions. Windward work is the particular joy of S boat sailing. Large total sail area and the presence of most of this in the mainsail (which "lifts" easily) combine with low wetted surface to yield outstanding performance in light air. The large sail area is carried beautifully in heavy air, thanks to the heavy keel. The slack bilges permit ready heeling in light-to-moderate breezes, but the righting moment increases rapidly as the lever arm of the keel lengthens with heeling; the boat becomes enormously stiff in the rail-down condition. One might still inquire whether a larger jib and smaller mainsail wouldn't be sufficiently more efficient to warrant putting up with the poorer handling qualities implicit in them (and the hull form they require). A one-design boat can always sacrifice some speed for pleasure, utility, safety, etc., but is such a sacrifice involved here? - and if so, how much? There has been much confusion on this point. The popularity of the large genoa jib and relatively small mainsail in cruising classes does suggest that this combination produces a large forward thrust per unit sail area, since the various handicapping formulas used for rating cruising boats are all based on sail area. However, the genoa jib also produces relatively more side force and heeling per unit sail area (see Morwood's "sailing aerodynamics"). Thus, a boat with relatively large mainsail and small jib is able to carry more total sail area than one with the typical genoa jib setup - and will normally do so unless it is tied to a rating rule which penalizes sail area as such. This would seem to be the explanation for the fact that one doesn't find genoa jibs in those development classes whose rating formulas ignore sail area. Furthermore, the faster one designs have sheeting bases that are too narrow for effective use of a genoa jib. Anyway, who wants a genoa jib in a one-design racing boat? Good visibility and easy tacking features are too important in heavy traffic. Running backstays are no trouble at all, but genoa sheets are something else again. The runners, incidentally, not only permit the use of a large mainsail, with center of effort (and therefore also center of lateral resistance) well aft, but also enable the jibstay to be kept taut. The smallness of the jib means that light air performance is not reduced significantly by the use of a jib boom. The fact that the jib, as well as the main, is self-trimming in windward work means that the boat can easily be sailed single-handedly, as long as no spinnaker is carried. The mast curvature is seemingly a very modern feature. It effectively halves the strain applied to the mast in extreme conditions by providing an equilibrium curvature for use in medium breezes (the mast is straightened in light air). It also varies the effective draft of the sail in the appropriate way as the boom is sheeted in and out on various courses. No article on the Herreshoff's S boat design would be complete if it didn't mention the old Universal rating rule, since the Herreshoff S boats were originally conceived not only to race among themselves on a one-design basis but also to race against other boats designed to the S-rating of this rule. Under the Universal formula, boats tended to be built to the "top-of-the-rule", i.e. to be heavily ballasted and carry large spreads of canvas. The cost of such boats was high, and the rule was ultimately abandoned. However, as noted above, boats of this type perform well over a broader range of conditions than modestly canvassed boats of very light displacement, although the latter will often perform slightly better under the precise conditions (usually medium wind) for which they are designed. Any reasonable boat is a pleasure to sail in medium wind! Those who sail certain old Universal relay boats can enjoy light airs and heavy blows as well.    Please note: Prints of the S-boat image above can be purchased online at www.brayprints. com. Custom colors and captions are available.