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 Van Gorkom Yacht Design and Perrotti
Performance Design and have teamed up to create
a
new Volvo 70 for the 2005-2006 Volvo Ocean Race. Together, we have
helped sculpt the new Volvo 70 Rule, and have created a first
generation design with promising performance. Here's an inside look at
our work.
"The starting
point is a brand new, state of the art, 70' monohull race-boat. This
open design will have a canting keel and a choice of multiple rudders /
daggerboards. Above all, it will be very fast and exciting to sail. The
prescribed rule will remain relatively open, presenting a challenge and
test for designers. The new Volvo Open 70 will be an easier boat to
sail, with fewer sails to handle and better living conditions for the
crew. The race rules will favor imagination, creativity and sailing
skills, and not an environment where the biggest purse necessarily
gives a bigger edge." So touts the organizers of the Volvo Ocean Race.
The Volvo Ocean
Race, previously known as the Whitbread Round the World Race, is an
enduring pinnacle of offshore racing. The battleground of this
grueling, global, monohull sailing competition pushes the skills of
team sailors and designers to their limits, and captures the spirit and
excitement of sailing enthusiasts everywhere.
Following
successful competitions in 80-foot IOR maxis and the more nimble Volvo
Ocean 60's, the next event introduces an exciting new class that will
continue to promote breakthrough innovation, design, and speed. On the
tails of the 2001-2002 race, the Volvo Ocean Race team solicited
extensive contributions from a consortium of a half-dozen designers
(ourselves included), as well as sailors and sponsors to help sculpt
the framework of this latest ocean going thoroughbred.
This culmination of
creativity and innovation has given birth to the Volvo 70 and a new
format of racing that couples long-distance offshore sailing with six
action-packed inshore stopovers. Starting from the Mediterranean on
November 5th, 2005, the race ports-of-call include Cape Town/South
Africa, Melbourne/Australia, Rio de Janeiro/Brazil,
Baltimore/Annapolis/USA, Southampton/UK, Goteborg/Sweden, and a finish
at a Baltic port (TBA).
The race
will be scored on a high-point system tiered to the number of competing
yachts. Using 12 entries as an example: On each of the seven ocean
legs, 1st, 2nd, 3rd placed finishers will receive 12, 11, 10 points,
respectively. Mid-ocean scoring gates (one or two per leg) add an
additional 6, 5.5, 5 points to the 1st, 2nd, 3rd boats to round these
locations. And each of the six in-port regattas will award 1st, 2nd,
3rd placed finishers with 6, 5.5, 5 points, respectively. The ocean
legs will account for 80% of the total point tally, while in-port,
round-the-cans sprints will account for 20%.
In its very
conception, the Volvo 70 is a recipe for success. Its ingredients are
simple - Sailors wanted speed, power, and comfort. Race organizers
wanted durability and safety. Sponsors wanted innovation and
excitement. Blend these ingredients together with a dose of careful
planning and management headed by CEO, Glenn Bourke, and Racing
Director, Andy Hindley, to create a winning game plan for sport at its
most exhilarating best.
 Volvo 70
Principal Dimensions
Like its
smaller 60-foot cousin, the Volvo 70 is a rule-based, box design with
an abundant allowance for creativity and speed potential, yet tempered
with prudent restrictions for safety. Let's examine the differences. With
an additional six feet of waterline length (and a displacement similar
to that of the smaller 60's), the Volvo 70 will turn the physics of
speed/length ratio into a record setting pace. 500+ mile days could be
the norm. Optimized towards off-the-wind sailing, hullforms will be
wide and shallow aft, with narrow forward entries. The narrow entry
offers minimum residuary (or wave) drag, while the broad, shallow stern
promotes favorable planing characteristics. Hollows are permitted only
in the bow, and locally in way of appendage attachments such as fin
dillets (a concave fillet) and rudder bearing installations.
Yachts
will have an open choice of multiple rudder / daggerboard options, the
restriction being that each appendage can only have one degree of
freedom (rotation, retraction, etc.). Dual rudders aft with port /
starboard retractable daggerboards may be typical. But keep your eyes
open too, for bow-rudder designs following the form of CBTF's "canting
ballast, twin foil" concept. A team's selected configuration will
intrinsically tradeoff: high aspect ratio fins for maximum lift
efficiency when on the wind or reaching; reduced wetted surface when
sailing downwind; maneuverability and round-the-cans acceleration; and
durability and robustness dictated by an extreme ocean environment.
After
much discussion amongst race organizers and sailors, water ballast in
wing tanks will not be allowed. However, nearly 320 gallons of water
ballast is permitted in an on-centerline, aft tank for optimizing trim
and waterline length. As a result, sailing displacements will be
lighter with hulls inherently designed with narrower maximum beams, as
the drive for a maximized righting arm using water ballast has been
eliminated. Stability, though, is not lacking.
The most intriguing feature
of the Volvo 70 is its canting keel and 9900 pound bulb. Dual (and
redundant, should one fail) hydraulic rams can rotate the CG of the
ballast package 40 degrees to weather to create a very significant 25%
increase in stability and power. A canting keel offers lower wetted
surface, less form drag, and less required weight than a conventional
keel. Coupled, these benefits enhance performance dramatically, with
prior success demonstrated in the proving grounds of single-handed
round-the-word circuits.
The enticement of added stability is answered by a large, powerful sail
plan. Fractionally rigged, with a large, full roach mainsail, the sail
plan gains added power from masthead spinnakers and a Code Zero type
sail. A fixed (non-articulating) bowsprit extends 6 feet beyond the
bow, enabling easily tacked chute flying. Mainsail area approaches 2000
square feet, with spinnakers encompassing up to 5600 square feet of
area. The trick to success, though, is inventory. In an effort to keep
team campaign costs in check, Volvo Ocean Race organizers have tightly
limited the number of sails available to each team. Capped at 24 for
the entire race (no more than three mainsails), each leg is further
limited to eleven primary sails: one mainsail, four headsails
(including a staysail), one reacher, and five spinnakers -- at least
two of which shall be a fractionally flown. Storm sails are unlimited.
Sails with major recuts will be re-measured as new sails. In essence,
the ultimate power of the boat will be dramatically affected by the
team's ability to efficiently design, nurture, and maintain their
limited quiver of carefully conceived sails.
Sail shapes
must be carefully examined in the design stage to optimize wind speed
crossovers supplemented by the added stability of the canting keel.
Further, sails must have versatility for rapid-paced, round-the-buoy
racing, where use of the canting keel may be limited from a practical
sense. Interestingly, carbon sails will not be allowed, both from a
cost-savings standpoint, as well as the threat of their detrimental
impact on radar transmission.
Volvo 70's must be designed
to stringent large-heel-angle stability criteria. While a canting keel
increases stability (or righting moment) dramatically under typical
sailing conditions (say 30 degrees of heel), its offset CG actually
works against a self-righting tendency at large, knockdown heel angles.
Accordingly, Volvo 70 Rule developers have closely examined limitations
on hull displacement and beam that affect form stability, with
additional limitations on keel weight and keel swing angles. Each yacht
shall have a designer-calculated limit of positive stability greater
than 115 degrees, with appendages positioned in a worst-case scenario.
In addition, each boat must successfully self-right from a 180-degree
inversion using only manual power to articulate the keel.
 The finer
details of the new Volvo 70 class have been largely driven by sailors'
recommendations for ergonomic efficiency, both above deck and below.
The Rule endeavors to provide some rudimentary level of comfort - a
little corner of home in the roaring southern oceans. Well, maybe not
luxurious, but substantially better than the 60's. A limited sail
inventory translates to more available space down below, and the Volvo
70 puts this to good use. Each boat will have a dedicated navigation
station, and a separate, dedicated media center. A minimum of ten
berths provides for less "hot bunkings." Heaters will provide welcomed
comfort in the chilled waters of the southern ocean. The galley
encompasses a two-burner stove, sink, and reasonable area of counter
space. To buffer the hygienic preparation of food, an additional sink
is required for general use, separate from the galley. And, most
enticingly, the crew will have the luxury of a separate toilet
enclosure offering some measure of privacy.
Crew numbers have been
reduced from 60-foot standards. An all-male crew will be limited to
nine. A mixed crew (at least five women) will be limited to 10, and an
all-female team may have up to 11 crew onboard. During in-port races,
each team may take on one extra crewmember, likely with specialized
local-knowledge or fleet racing skills. Additionally, up to three
non-participating representatives from the syndicate, sponsors, or
media may join the in-port racing.
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