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2008/02/05 - 09h30
Exactly 23 hours
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| Jules Verne Trophy |
| Still on the austral edge of the Saint Helena High, Groupama 3 has had to deal with a breeze, which has shifted slightly to
the West, the crew forced to reposition themselves slightly to the SE. The Cape of Good Hope is now only one good day ahead
of them...
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By homing in on the African continent at high speed (an average of almost 27 knots in 24 hours), Groupama 3 will have
to leave the Saint Helena High to pass across into the Indian ocean. The reasons for this are that as they sail along the
southern edge of this high pressure, the curve of isobars are bending inwards parallel to the coast of South Africa and the
wind is turning (backing) from the NW to W, then to the SW... Logically, the giant trimaran had to make an additional gybe
last night at around 0400 UT so as not to adopt this curved trajectory, which was gently carrying them up towards the NE.
Evidently, in relation to Orange II's course in 2005, which was remarkably pure from the equator, Groupama 3's wake
appears more chaotic due to the need to slip along between the high pressure to the North and the lows to the South. By shifting
to the W, the downwind conditions are forcing Franck Cammas and his crew to zigzag their way along, on starboard tack this
Tuesday morning and probably port tack at midday. Indeed a multihull mustn't make headway with the wind directly on its tail
but instead with an attacking angle of around 40° to the breeze: if there is a W'ly wind, as there is now, the trimaran can
chose between a course at 60° (ENE) or a heading of 150° (SSE). To optimise its trajectory, the navigator will have to benefit
from the slightest wind shift to reposition itself. Fortunately, behind the low, which is passing under Groupama 3, the breeze
will back from the W to the SW, enabling the giant trimaran to follow a more direct course on starboard tack.
Of
note is the fact that at 0700 UT this Tuesday, Bruno Peyron `virtually' passed within a few miles of Franck Cammas' position
at 0800 UT: an actual separation of 23 hours then between the two multihulls, three years apart...
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