Here are photos from the recent self righting inversion test prior to
the start of the Around Alone. For more up to date information,
please visit Everest
Horizontal's own website.
Now being campaigned as Everest
Horizontal...
When
I first met Bob Gay, he had already accomplished what is probably the
most difficult challenge facing any solo sailor intent on a round the
globe race - that of obtaining sponsorship. Corporate America has been slow to recognize the potential
marketing value of high profile sailboat race campaigns. Bob had
presented his goals to Ascend Communications in a language they can
understand - a business plan. Not long after construction contracts
were signed, Ascend merged with Lucent Technologies, a communications
giant who immediately recognized the fit - a solo adventurer facing
brutal challenges in the most remote part of the planet, all the while
immediately connected by phone, fax, and email with sound and video to
the population at large, at home in their civilized world - an
aquanaut on an electronic umbilical cord.
They named the yacht “Convergence”,
reflecting the merging of technologies and communications at the turn
of the millennium.
Bob’s
goal has been as steadfast as it is simple: he intends to be the first
American to complete a Vendee Globe race.
The Vendee Globe is the most difficult sailboat race ever
conceived - one man, alone, non stop, around the world.
The middle third of the race is sailed in the high winds and
awesome seas of the Southern Ocean. It has been jokingly (and not
inaccurately) called “the Round Antarctica Race”.
The
Vendee Globe is open to boats between 50 and 60 feet with one class
and no rating - first to finish wins the race. On first thought, it
would seem unwise to enter the race with the smallest boat in the
class. However, this choice makes sense when evaluated against Bob’s
goal. The Open 50’s are tremendously fast and powerful. An Open 60
is all the more so, to the point where you have to ask whether the
boat or the skipper is in charge.
Only one 60 managed to complete the last Around Alone race
without major catastrophe. The
Vendee Globe, being a non stop race, is even more a war of attrition
than the Around Alone. A
50 is simply more likely to finish than a 60.
We
are not so arrogant as to expect to beat the 60 footers to the finish
line. After all, the French have long dominated these races with
excellent sailors and fast boats. However, we do expect to be nipping
at their heels. Our
design challenge has been to create a boat that increases the safety
margin and is extremely rugged while still advancing the performance
envelope beyond the current crop of Open 50s.
For
downwind speed, weight savings is the number one concern. Contrarily,
in a war of attrition, redundancy and reliability become the key
words. The “reliability first” concept made the choice of water
ballast over swinging keel an easy one. Evidence of this philosophy is
evident throughout the boat, especially in the systems - multiple
systems for electrical generation, multiple autopilots, watermakers,
GPS systems, communication systems.
Reliability
means minimizing the risk of damage. Following this line of thinking,
we carried the keel right through to the deck. This strong and
structurally efficient geometry, in combination with Kevlar grounding
straps similar to those used in my multihull daggerboard trunks should
make the keel to hull attachment stronger than the steel fin itself.
Open
class rules now require five watertight bulkheads and positive
flotation even with all watertight compartments violated. Let’s hope
the proclivity for abandoning boats in the Southern Ocean is a thing
of the past, or contestants will soon have more than icebergs to worry
about. Round the world races could become a trip down memory lane.
James
Betts Enterprises was completing
construction of America True as our design was being finalized. I was
pleased that Jim Betts was interested in using prepregs for the Lucent
project. Hull, deck, and
all interior bulkheads and structure were built of YLA supplied
prepreg carbon skins over Baltec’s new SuperLite Balsa core. Outer
skin of the hull/deck shell included two layers of S-glass/Kevlar
hybrid for impact resistance and crack arrest.
Betts
and his versatile team also built the prepreg rudder posts, the rudder
blades, the keel fin weldment. They vacuum formed the windows, and
installed the engine, generator, and water ballast system.
With
the new positive flotation requirement, we decided to increase the
core thickness of the hull/deck sandwich. A thicker sandwich is
stronger and stiffer, in this case well in excess of ABS guidelines.
On
the engineering fun side, we developed a bowling ball impact test
models to represent a collision at 25 knots. Our plywood baseline
panel was demolished, while the prepreg/balsa panel received only a
scuff mark. Continuing the evaluation, the composite panel survived a
sledgehammer test, finally failing under splitting wedge impact.
We’ve instructed Bob to avoid splitting wedges.
The
essence of the Open Class Monohull rule is a limit of 10 degrees heel
with all moveable ballast shifted. This simple restriction defines the entire character of the
boats. A wide hull is extremely stable at small heel angles. More
stable hull means more ballast can be shifted,
means even more stability, means more sail can be carried,
means astronomical sail area to displacement ratios.
Unfortunately, wide boats are also stable upside down. Upside
down is slow and unpleasant - so difficult to stir your stew or to
find your toothbrush.
In
the early design phase, considerable effort was put into beam
optimization and capsize recovery. Essentially the goal was to make
the boat powerful in the sailing heel range, yet unstable when
inverted. We accomplished this by a “convergence” of several
features-
·
Cambered decks and a large coachroof - These features have been
employed by the European designers recently. We pushed them a little
further.
·
Large radius to the hull deck edge - This very effectively
reduces the waterplane area when inverted and should help a bit with
tripping in a high speed broach. Further benefits are reduced windage,
reduced weight, rapid dumping of foredeck water, and increased
strength and rigidity of the hull/deck shell.
·
Wide cockpit - Again our goal was to eliminate inverted
waterplane. The cockpit sole extends all the way out to the face of
the water ballast tanks. This feature very significantly improves
recovery from inversion. In fact, if ballast tanks are full on one
side the boat is completely unstable in the inverted position and will
complete a barrel roll and return to upright.
·
Ability to fill ballast tanks when inverted. In the unlikely
event the boat capsizes with tanks empty and stays there, ballast
tanks are plumbed to allow them
to be filled with the boat inverted, which will cause her to self
right.
·
Watertight mast - A watertight mast greatly enhances the
ability of the boat to right from an extreme broach. To do this, of
course, it has to survive the roll. We applied extra carbon laminate
in the hoop direction to withstand the tremendous water pressure the
mast would see if immersed. This extra off axis laminate will make the
mast significantly more rugged under normal use as well. With a
watertight mast, the choice of all external halyards was obvious; and
I believe this makes sense in any case for a single-handed ocean race.
Easy check for chafe, easy replacement. Sometimes low tech is the best
choice.
·
Higher ballast ratio - Convergence has a heavier bulb than most of the current fleet of
Open 50s. Probably this is the most significant feature on the list;
because the lower center of gravity is most effective when the boat is
knocked to 90 degrees. Bigger bulb and a buoyant mast will
make it highly unlikely that the boat will invert in the first
place. Ignoring the
watertight mast, limit of positive stability is about 130 degrees.
Including watertight mast, it is about 155 degrees. With water ballast
on one side, it is 180 degrees.
The
Vendee Globe is primarily a downwind race, and buoyancy forward will
allow the boat to be pushed hard in big seas. In addition to rather
high forward freeboard, bow sections are full near the sheerline.
A retracting and articulating bowsprit is mounted in a raised
pivot ball at the stem, which serves a second function as a wave
break. Ancient Polynesian canoes had a similar feature - a raised stem
piece which serves to relieve downward pressure when the foredeck is
driven under water. Water which does make it onto the foredeck will be
deflected outward by the wide flaring house.
Open
class designs are not at their best upwind. Ultra light displacement
and wide beam do not make for a pleasant ride against the seas. We’ve
attempted to improve on this scenario somewhat by keeping the bow
relatively fine at waterline and below. Furthermore, our studies
indicated that a slight increase in keel fin area would enhance upwind
speeds. Larger fin area made a steel weldment an obvious choice over a
milled steel fin; and with that decision it was logical to use the fin
as a diesel tank.
These
races are won by boats which sail fast in the Atlantic legs and
survive the Southern Ocean leg. By not pushing transom beam as hard as
most existing designs, we sacrifice some power but reduce wetted
surface in light air. Further, the more balanced hull shape has a
gentler edge of control and can often be pushed at a higher
performance percentage.
Remarkably,
non-dimensional performance ratios for sail area, displacement, wetted
surface, and stability are quite similar to those on the Antrim 27, a
boat of approximately half the waterline length.
In effect, water ballast replaces crew weight on the rail. High
stability allows for a big sail plan, which drives the ultra light
hull at exhilarating speeds.
A
comfortable crew will push the boat harder than one who is cold,
tired, and miserable. Obviously comfort is a relative term here.
We extended the lines of the house aft to form a rigid dodger,
which will be a welcome feature both in cold weather and under the hot
tropical sun. A small
diesel heater will help in the cold climates, and seemed a justifiable
addition to the tight fuel budget.
Designing
a boat for the Vendee Globe is a privilege, a challenge, a thrill, and
a responsibility. We thank Lucent for their support and Bob for his
confidence; and look forward to greeting him at the finish line.
Open
50 CONVERGENCE
| LOA |
15.24 m |
50 ft |
| LWL |
15.15 m |
49.7 ft |
| Beam |
4.35 m |
14.3
ft |
| Draft (Board up/down) |
3.75 m |
12.3 ft |
| Displacement (empty) |
6.2 t |
13700 lbs. |
| Displacement (sailing) |
7.2 t |
15900 lbs. |
| Ballast |
2.8 t |
6200 lbs. |
| Water Ballast |
1.8 t |
4000
lbs. |
| Mast (above deck) |
21.3 m |
69.9 ft. |
| Mast (above water) |
22.5 m |
73.8' |
| Main |
89.6 sq. m |
964 sq. ft. |
| Jib |
78.8 sq. m |
526 sq. ft. |
| Genoa |
73.4 sq. m |
790 sq. ft. |
| Spinnaker |
206 sq. m |
2217 sq. ft. |
| Displacement
/ Length |
50 |
| Sail Area /
Displacement |
49 |
