Delta Lloyd, skippered by Roberto Bermudez (ESP) at the start of leg 6 of the Volvo Ocean Race, from Rio de Janeiro to Boston. Image copyright Rick Tomlinson/Volvo Ocean Race.
by Wouter Verbraak (navigator)
Are those guys drunk?
Following our wallowing tracks one might think that we have supplemented our freeze dried food with some caipirinhas from Brazil. Certainly a little cocktail at sunset would be very welcome indeed, but I can guarantee you, there is not a drop of alcohol to be found on our boat. So what is up with our drunken man's track?
Some call it myth, some live by it, and onboard it is known as the diurnal variation [fluctuations that occur during each day]. Some of the more funny guys amongst us bastardise it to di-urinal variation, but the understanding is the same. If you believe the theory this variation in the wind speed and direction is typical for the trades and goes through a daily cycle. The mornings bring more wind and more left wind, the afternoons bring lighter and more right wind. At the same time the evening brings squalls and more left wind again, and night time has some lighter and more right wind.
As we are now all close reaching, the differences in boatspeed for a slight change in wind angle are quite significant. With the winds doing their daily dance, instead of staying on course and adjusting the sails, we are following their lead.
We know that it is OK to be a bit below course in the mornings and evenings and maintain our speed as we can expect to be lifted and lighter again later.
Significant gains can be made by sailing this way, but it can be risky business as well if the expected lift in the afternoon doesn't come.
Yesterday and this morning have been perfect examples, and one might start to actually believe in this seaman's tale. It all helps my nerves, as it means that the models that are not very good at picking up this oscillation are not complete rubbish and can be used for the bigger picture plan.
Today looks to be a crucial day for the fleet. We are passing the most eastern tip of Brasil, and it is here that the differences between being inshore or offshore are felt best. We have invested in a more offshore position, which has meant slower sailing and more distance travelled and today we will have to see if we can reap the benefits of this. The forecast certainly shows light winds along the shore this afternoon, so at the moment we are making sure we are keeping our easterly position to the fleet.
Models however are notoriously poor in this area, and it always throws a little curve ball just when you think you have figured it all out. Nothing to do but to keep sailing hard, stay focused and monitor the fleet. Not long now to the scoring gate and boy, are the guys onboard keen to keep our second place!
Volvo Ocean Race
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