51
SVN Solovelanet Global
Every braking, in boats as well as in cars and motor-
bikes, always produces a forward pitching moment.
The bow tends to duck down, foreseeing a possible
very bad duck dive. This tendency can be compen-
sated by acting of the rudder trim (negative trim), or
by executing the tack or gybe fast enough to limit
the loss of speed. Once the bow (or the stern) has
been turned through the wind, the just-submerged
foil should be rapidly re-opened downwind, while
the newly-windward foil should be opened more
gradually to provide righting moment.
All in all, once again the America's Cup will be a mat-
ter of details, crew's coordination and teamwork, as
well as its full knowledge of the boat in every wind
and see condition. Because of Coronavirus, we will
be able to see the AC75 officially flying not in Cagliari
nor in Portsmouth, but directly in Auckland in 2021.
Hoping to fly faster than any virus.
Daniele Cirigliano, 27 years old, gra-
duate student in aeronautical engine-
ering at the University of Stuttgart. He
got his sailing training in La Maddale-
na and in the Tuscan Archipelago
The author
Here above, it is shown how the D-shaped
mast with the two mainsails hoisted at its ed-
ges creates a much smoother flow than that
created on a traditional mast where the flow
meets a step between the mast and the sail.
Here below, the two mainsails of an AC75
Traditional
mast
D shape
mast
Traditional mainsail
Double mainsail
4
5
Flat surface in the centre
of the boat to limit the
spill-over of the wind that
tries to go from upwind to
compensate the downwind
depression running under the
mainsail
