mardi 30 juin 2015

LITTLE AMERICA'S CUP BOOK - four side stories - PART TWO

Dulcinae (1970)

The high aspect ratio of Dulcinae's first wing blatantly exposed the influence of an aircraft pilot
© François Chevalier 2015

Having completed 90 drawings for the book on the History of the Little America's Cup, I lay puzzled when someone asked me which C-class I preferred. Finally, I settled in Dulcinae, largely unknown, although she sums up the spirit of this race well.

The Little America's Cup has a fascinating history of international challengers competing in the World's fastest catamarans, all measuring 25 ft in length, 14ft in beam and with a 300 sq ft sailplan. Since 1961 this race has given rise of the wildest of ideas, with the development wingsails tried in the first decade and many other astonishing innovations, which shall be discussed before the launch of the book.

Dulcinea was designed in 1970 for 4-time gold medal olympian Paul Elvstrøm, by Ib Pors Nielsen, an engineer who had previously managed the Danish team in the Little America's Cup. Leif Wagner Schmidt and Hans Gert Frederiksen, the designers of the challenger Opus III, had won over the defender Ocelot, putting an end to eight years of British dominance in the event. Paul Elvstrøm had attended the event at the Thorpe Bay Yacht Club to support his fellow countrymen and had been won over by the atmosphere, the technology and the speed of the C-class.

In 1969 the Danes only had one C-class, so it was impossible train in match racing. They had two boats but only one rig: Opus III had inherited it from Opus II. Their victory was due in large part to an ageing defender, Ocelot. Thus Elvstrøm and Nielsen's project was a good opportunity to defend the Little America's Cup in Denmark. Schmidt and Frederiksen were satisfied with the lines of Opus III, of which they raise the bow, and for which they develop a wingmast with a larger sail area. On his part, Nielsen is decided on producing a revolutionary catamaran, featuring a wing with high aspect ratio, extending to a cylindrical base, and capable of rotating 360°. He completely removes sails, providing the wing with a trailing edge flap wide enough to offer substantial trimming possibilities and remain efficient downwind.

Ib Pors Nielsen, who passed away in 2012, designed many trimarans after Dulcinea, though all more conventional in type.

Dulcinea's deck layout clearly shows the integrated circular wing base.

Dulcinea's lines plan, the ratio between length and height is 3 to 10

The mast sections are NACA 682-615 profiles, with a 16% thickness/chord ratio at the base.

A puzzled Elvstrøm contemplates the assembly.
With Dulcinea on her side, Elvstrøm holds one of the gym ball bearings in his left hand.
A timid outing aboard Dulcinea, the deck is not ideal for hiking, the nicks in the hulls to rest one's feet are not reassuring, especially as the boat is not fitted with stays or even a trapeze.

Dulcinea, between the successful 1969 challenger and the unsuccessful 1970 defender.

Dulcinea became the first European C-class catamaran to feature a wingsail when she was launched, shortly before Schmidt and Frederiksen's Sleipner. She bore sail number D2. The turnplate base, integrated in the deck, measured 2.70m in diameter and revolved on a peculiar ball bearing arrangement: 50 gym balls in a track to dampen the loads! The wing was a self-standing NACA 682-615 airfoil measuring 12m and weighing 70kg. The frame build was moulded wood, aeronautical plywood as well as expanded polystyrene of 15kg/m³ for the sections.
During Dulcinea's first outing, Elvstrøm was surprised by the wing's power, and a trapeze, deemed unnecessary due to the wing's ability to turn about completely, was found lacking: the catamaran heeled, then accelerated, broached, finally capsizing and breaking the wing. Repairs took a few days, too long for Dulcinea compete against her fellow contender Sleipner, although she did manage astonish the journalists aboard a powerboat as she overtook them. 

Dulcinea, on her side on the beach, could have revolutionised yacht design, had she only a trapeze...

Splice (1976)

Splice resembled no other C-class: Designed by a glider specialist, she was a formidable upwind performer, but inefficient at other points of sail
Splice was the only South African C-class catamaran, but what a C-class she was! She made all heads turn when she arrived on the Eastern seaboard for the 1976 Little America's Cup selection trials. I would not know which unique attribute to describe first. To start with, she complies with the C-class, being 25ft in length, 14ft in breadth and with sail area capped at 300 sq ft. However, in principal and by definition, there would be a crew of two, but Splice's cockpit, below the wing, only has space for one. And because the wing takes the entire width of the forward crossbeam, the other crewmember is hard pressed to change sides. The wingsail had one trailing edge flap that spans the entire height, with a stabilizing aftercanard, which itself features a trailing edge flap. This configuration vaguely resembled a vane steering system developed in Seattle, WA. The two hulls was linked by a single large crossbeam, although the wing base was wider still. 
During the Second World War, Norwegian Fin Utne built Flaunder, a winged sailboat that featured a self-steering aftercanard.
(AYRS collection)

The Amateur Yacht Research Society had produced this sketch of Splice in March 1976, indicating that a Russian researcher had proposed a similar closed cockpit on a land yacht in 1940.
The wingsail had a particularly high aspect ratio, and turned 360° on a hard wooden base disk. There was no trapeze, no stays, and the helmsman remained enclosed in his plexiglass cockpit at all times. The aftercanard and its flap were controlled from the cockpit, and determined the incidence of the wing and its flap. The rudders were pedal-controlled. The pilot, whilst in the cockpit generated no air drag, but could not get out, and thus could not hike. There was a single centerboard located beneath the wingsail which swung laterally into place! The hulls hulls had very low freeboard, the bows were equipped with bulbs, similarly to large displacement vessels. The protrusion extended almost to the crossbeam. The rudders could retract into slots in the double-ender sterns. 

Splice's designer and builder, South African 54 year-old Patrick Beatty, from Bedfordview, a suburb of Johannesburg, was a glider pilot, engineer and builder. He spent three years to develop this C-class, testing her in a lake close to Johannesburg before shipping her to Rowayton, CT. In September 1975, the Roton Point Sailing Association was bustling with activity, with three weeks of competition: the NAMSA championship, the Pacific and Atlantic championship, followed by the selection trials for the Little America's Cup, to be held in Australia in February, against Miss Nylex

For Splice's first outing, Beatty wanted to sail singlehandedly, but the sailing committee retorted that the C-class rules requires a crew of two, so a young volunteer was designed to sail with him. Considering the dangers that he would encounter in tacks, as well as the risks of impaling onto the centerboard lever, Beatty was eventually authorised to sail alone. 

South African Patrick Beatty before Splice, the bulbous bows showing slightly 
in lower left hand side. 
(Steve Clark collection)
Splice immediately displayed formidable upwind performance, with exceptional heading. However, on the reaching tacks, her lateral stability showed weakness, with her leeward hull sinking distinctly. On the running tacks, the wingsail gave a lacklustre performance, her flaps being to small to generate much lift. Her only hope in getting to the mark was to beat downwind on a series of broad reaches and gybes. 
The New York Times used this photography of Splice to relate the Little America's Cup at the Roton Point Sailing Association, in Rowayton, Long Island.
(photographer: Joanne A. Fishman)

During Splice's first outing, the extra crew was lying on the deck et Beatty was at the cockpit controls, just like on his gliders.
(photographer: Dan Nerney)
That first day of racing was the last. A violent storm damaged Splice overnight, and repairs could not be carried out to make the selection trials. Beatty truncated the wingsail and donated it to Professor Sam Bradfield of Stonybrook University. Bradfield, a hydrofoil pioneer, kept Splice a short while as Beatty returned to his home country, never sailing in the C-class again. He and his wife died in a car accident in 1991. 

After the storm, Beatty decided to lighten and truncate Splice's wingsail, and put her up for sale before returning to South Africa. 
(Steve Clark collection)
Californian Alex Kozloff won the American challenger selection trials aboard Aquarius V, even though Patient Lady III had dominated the championships, but her wingsail was broken in the last week of racing. In February 1976, Alex Kozloff successfully defended the American flag against Miss Nylex, winner of the previous edition. 

Alex Kozloff, aerodynamicist, is a light catamaran expert. He was convinced that, in light airs, Aquarius V's soft sails could beat a wingsail if the overall weight of the boat was light enough. The 1976 Little America's Cup proved him right and the Australian Miss Nylex was beaten 4 races to 3.
© François Chevalier 2015
The "Little America's Cup" has been forbidden from serving as an official name, after having been affectionately known as such ever since its inception in 1961. Over the years, it has been known as the International Catamaran Challenge Trophy and the International C-Class Catamaran Championships. It will be raced again in September 2015. 

François Chevalier - Translation: Donan Raven

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