May 22, 2010

The R Class

R Class Development and History

image-10As long as there have been sailboats, people have wanted to race them. In the earliest days of yacht racing, including the first America’s Cup races raced off the Isle of Wight in 1851, the fastest boat was the winner regardless of how large or how much sail. As racing became more sophisticated, different rules were proposed based on a vessel’s length or displacement, but each had only local followings or major failings. A standardized classification of yachts was proposed by Nathanial Herreshoff in 1898 and adopted several years later by the forerunner of the North American Yacht Racing Union (itself the forerunner of today’s Canadian Yachting Association and US Sailing). This rule came to be known as the Universal Rule.

Under this Universal Rule a Rating was calculated:

Rating (ft) = 0.18 * Length * √Sail Area

3√Displacement

Vessels which rated over 17 ft. and not over 20 ft or under were known as 20 footers and designated as R Class. Under the same rule vessels rated over 65 ft and not over 76 ft. were designated J Class – these became the famous, fabulous vessels that raced for the America’s Cup in the 1930′s.

It is important to note that 20 foot refers to the rating by formula, not the actual length of the vessel which was decided by the designer to meet his idea of optimization of the formula.

The first R Class boats were designed and raced in the years leading up to
World War I.

The following excerpt of an article by J.W. Streeter (taken from Sailing Craft – ed. Edwin Schoettle, MacMillan 1928) describes the early development of R Class Sloops.

“In America it is safe to say that four-fifths of the yacht races are sailed between boats built from the same plans. This predominance of one-design classes has made many of the younger yachtsmen think the progress of the sport can correctly be measured by the increase in the number of boats racing. There is no doubt that this is a criterion of its popularity, but they do not look deep enough if they are to judge the advance in the art of designing. It is the open-class racing, the racing in which every boat represents an experiment or a compromise, that make yachts improve. The older men can well remember when there was no such thing as a group- of boats with identical lines; all of the racing was carried on under rating rules, some of them good and some bad. Many craft of that period would seem ridiculous now, but credit must be given to the men who kept trying new things and thus contributed to the knowledge that permits us to build the fine sailing yachts we have today.

The general interest in boat racing has increased tenfold since the days when clumsy sand-baggers were raced for cash prizes, and the designers have tried hard to keep step. They have not been aided as they should have been, for with the advent of the flying start and other refinements of the racing rules the average yachtsman has come to think less of his boat and more of the technique of the game. This change of attitude has played a part in establishing the immense popularity of the one-design classes in this country.

In the majority of localities, and for most people, open-class racing is impractical, and any one of the countless supporters of the other branch of the sport can advance strong arguments that appeal to a great number of men. In spite of this, the best distributed and most active class of sloops in North America is the R Class. This is a distinctly open class, for the boats are of widely varied design but are built to rate just below 20 feet under the Universal Rule. Among the owners of these yachts are many of the most prominent yachtsmen of their different localities; partly because they wish to enjoy the unrivaled competition that this class affords, but more because they desire to take part in the movement that has ushered in most of the improving innovations of recent years.

To understand this development, it is necessary to become acquainted with the rule which was originally conceived in 1898, by Nathanial Herreshoff, the dean of American yacht designers. Seven years later it was adopted by a conference in which most of the leading yacht clubs and associations were represented. Since then it has nominally been the official formula for the measurement of yachts. It is commonly expressed in this form:

R = 0.18 * L * √SA where: R= rating; L=length; SA=sail area; D=displacement

3√D

By this means length and sail area, the two factors upon which speed is dependent, is controlled and a premium is placed on weight which to a great extent determines stability. A sensible form is assured by the so-called quarter beam penalty, which prohibits excessively full ends. There is a definite limit to the draught based on the waterline length, and there is a point beyond which credit is not given for extra displacement. In practice, the relation between length and displacement is almost constant; the result being that, while the sail area remains practically the same, the waterline length varies considerably and the displacement varies with it.

The application of this rule can be best illustrated by a typical sloop of the class. The Ardette which was designed by Charles D. Mower in 1925 for Donald H. Cowl, represents the class as a whole better than any of the boats that have been conspicuously successful in one locality. Her lines and sail plans show strength and character. Her dimensions are as follows: 38’ LOA x 25’ LWL x 7’3” Beam x 5’8” Draft with 582 sq.ft. of sail. It will be found that these can be substituted in the rating formula and a value of 19.76 is obtained, which is the same as all the others, for they have to be just below 20.

No two yachtsmen will agree on what is the finest kind of boat, but few can have the hardihood to say that the Ardette is not an extraordinarily fine boat for racing. It is hard to imagine a stauncher and handier sloop build to a rule allowing any freedom to the designer. The opinion of many is that she and the boats like her are the best yachts of their size afloat. It is not because she is the fastest of the class that such emphasis is laid on the Ardette, but rather because she is a consistent all-weather performer without any of features that detract from her practical qualities. Mr. Mower has been connected wit the R Class since its beginning, and his productions are racing at or near the top wherever these sloops are found.

In the first years of the Universal Rule there were few boats built to Class R, and the designers, after the practice of the time, made them comparatively short; for it was not realized that a boat weighing 13,000 lbs could be made to go faster than a boat with the same sail area and half that weight. This explains the increase in size, and the consequent displacement of the sloops to this day. In 1915, F.W. Goeller Jr. designed several R’s 21’8” on the water line displacing about 6,500 lbs, while Hereshoff, in 1926, went to about the limit when he produced the Grayling 27’ long and weighing nearly seven tons. Since the difficulty of handling a boat is roughly proportional to the sail area, it is readily apparent that an advance has been made; for not many years ago no one thought that 600 sq.ft. of sail could ever propel a sloop the size of a modern 20-rater at a reasonable speed.

In spite of the fact that the designers were not very sure of their ground, some fine R’s were produced before the war, and a number are still performing creditably. Goeller’s Ariel, Owen’s Nirvana, and Mower’s Neahga can be listed among these.

When racing was revived at Marblehead after the war, the R Class was among the first to appear. The conspicuous feature of the boats of that period was the height of the rigs. It had been conclusively proved that the jib-headed mainsail was superior to the gaff rig. Furthermore, a narrow sails with a long luff was found superior to a sail of the same area but longer on the boom. Masts became excessively high, the limit coming when George Owen produced the Ruweida II, which dispensed with a jib and set its sail on a mast whose truck was 66 ft above the water, while the boom was only 18 ft. long. She was fast, and under reduced rig proved very powerful.

However, these tall-rigged boats met their match when, in 1920, A.G. Hanan, one of the best amateur designers the sport has known, brought his beautifully proportioned Ariel to Marblehead in search of the Greenwich Cup. The Ariel and the Rogue, which was designed in 1917 by John Alden and sailed by Burton Hart, beat the Ruweida II and Alastor, a somewhat similar boat in three races. Soon afterwards, the height of mast was restricted and a fifth of the total area had to be carried in a jib.

Today the class is found on both coasts and on the Great Lakes, and spirited racing is had in more than a score of places each season.”

Information courtesy of ladyvan.com