When your boat heels 10 degrees and you rise 15 to
20 ft (4.6 to 6 m) in the air, you’re experiencing the
elevator sensation skipper Franck Cammas feels every time
he helms the ‘G’ Class trimaran Groupama 3. These
‘Giant’ (that’s what the ‘G’
stands for) multihulls were built to break ocean records:
distance records, around-the-world records and speed records.
They regularly sail at speeds in the mid-30 knot range, with
bursts into the 40s.
In 1998, Cammas was asked by Groupama Insurance to helm
Groupama and Groupama 2—both ORMA 60 trimarans—and
dominated this mainly inshore 60-ft racing class of multihulls.
When designing Groupama 3, Marc Peteghem and Vincent Prevost
scaled up their original ORMA 60 concept to G-Class size.
Franck Cammas was a young, up-and-coming sailor when he
was spotted by the Groupama Insurance Group and hired to
helm the company’s 60-ft ORMA trimarans, Groupama
1 and Groupama 2, on the Multicup circuit. In 9 years of
inshore racing, Cammas has been nearly unbeatable with 46
podiums and 26 first positions in 53 races. He is also a
4-time ORMA World Champion. Now skipper of the Harken-equipped
G Class Groupama 3, Cammas is in search of ocean records,
but will continue to race Groupama 2 on the ORMA class circuit
where he was so successful.
Groupama 3 is shorter than other boats
in the ‘G’ fleet, but much wider and half the
weight of its catamaran rival Orange II, the holder of the
Jules Verne (around the world) Trophy—a record high
on Groupama 3’s ‘to break’ list. Groupama’s
shorter length, wide stable platform, and lighterweight
philosophy generates enormous sail power that must be controlled.
Unlike Orange, this boat is optimized to sail fastest in
the lighter 10- to 20-knot winds of the Atlantic, but will
need to reef sooner than its rival in the Southern Ocean.
This design strategy has already proven a record setter.
Groupama 3 left January 24th for its Jules
Verne Trophy attempt: www.cammas-groupama.com
TAMING THE BEAST
In April 2005, three key members of the Groupama team traveled
to Harken
Pewaukee for intense brainstorming with Harken engineering
on building gear to control and transform Groupama’s
power into forward motion.
ENGINEERING MANAGER STEVE ORLEBEKE TALKS ‘G’
CLASS
Mainsheet System—Safe Working Load 44,300 lbs. (22
Tons)
Harken
decided to create a CRX-mega traveler on Groupama 3. Mega
multihulls had already successfully circumnavigated using
this traveler, and Harken felt it could handle the predicted
mainsheet load of 22 tons. These cars use roller bearings
instead of conventional ball bearings to handle the boat’s
huge sheet loads. The high-load roller bearings also allowed
Harken to design six short curved-race (the track the bearings
ride in) cars for easy travel and even loading on the horizontally
bent mainsheet track (curved track follows the arc of the
boom for consistent sheet tension when trimming) asked for
by the Groupama team. All block attachments and car-to-car
connections are ‘soft’ spliced ropes and LOUPS™
for strength and to save weight.
Battcar System—Safe Working Load 2270 kg
(5005 lb), Car Weight .8 kg (1.76 lb)
The Groupama Harken Battcar system is the smallest and lightest
we have ever designed for a boat this size. The mainsail
is huge—356 meters2 (3,832 ft2). To reef and control
this huge sail was a must, making a free-running ball bearing
system the only option.
The Groupama team wanted an 80-mm-wide Battcar system that
fit the back of their wing mast. Harken began by choosing
a track fastener diameter and then made the track as narrow
as possible, but still able to fit the fasteners. Ball bearings
were downsized from 12 to 10 mm and track bearing race angles
made into a tighter "V" shape to increase load-carrying
capacity. The result was a track width of 38 mm and batten
cars 90 mm wide.
Blocks and Sheaves—Safe Working Load 100
kg (220 lb) to 11,338 kg (12.5 Tons)
All blocks are custom-tailored to the boat’s specific
loads. For example, a 1.61 kg (3.5 lb) runner block has
an SWL of 11,338 kg (12.5 tons), while the mainsheet block
has an SWL of 6349 kg (7 tons). This style of block was
developed for the America’s Cup—simple, reliable
and efficient at high loads. Many feature drilled-out center
pins so a safety lashing can be installed through the block
center. All sideplates are CNC-machined of high-grade titanium
for strength. A lot of the sheaves, especially fixed halyard
sheaves in the mast, feature tulip-shaped grooves. These
groove shapes help guide lines into the sheaves at off angles
and prevent chafe on the sheave boxes.
Floating Jib Block—Safe Working Load 9070
kg (10 Tons), Weight 2.22 kg (7 lbs)
Groupama
3’s dimensions and sailplan place the jib clew right
over the net with no place to bolt down hardware to trim
the headsail. This was solved on the Orma 60 Groupama 2
by suspending a floating block on a soft bridle anchored
between the amas and main hull. To change the twist of the
sail, crew tension the bridle to lower the jib block. Bridle
tension goes up exponentially as the block gets lower.
Harken used this same principal on Groupama 3, but had
to design the block to function well under enormous loads—10
tons for the jib sheet. At the same time, we had to keep
the system lightweight. Harken used high-strength materials
such as titanium for the main structure. Soft, lightweight
LOUPS™ were used as attachments because they can articulate
under load.
Harken Winches
(...more)
Four powerful 1130STR racing winches (two primary and two
secondary) on each side of the cabintop control a confusing
tangle of lines that lead aft to the cockpit. Groupama also
uses three 880.3STR winches—one for the mainsheet
and two for the running backstays and mainsheet traveler
controls. All seven winches are connected by two horizontal
pedestals instead of standard belt-drive transmissions and
gear boxes for a lighter-weight system that needs much less
maintenance.  |