Thursday, 19 February 2009
VOR: Another Day, Another Dollar
Green Dragon hit rough weather, on leg 5 of the Volvo Ocean Race. Image copyright Guo Chuan/Green Dragon Racing/Volvo Ocean Race.
by Mark Chisnell
Another day, another 400 or so miles on the clock – wind speed: mid-teens; wind direction: northerly. Nothing much has changed. These are the humdrum miles, the 9-to-5 miles, the are-we-nearly-there-yet miles, the boat speed miles… this is where the speed kings earn their keep.
Taking home the big bucks were Torben Grael and Ericsson 4 – still topping the pile, with Ken Read and PUMA handcuffed to them for the road trip - the deficit locked in at around 10 miles.
By 10:00 ZULU this morning, the wind speed had eased just a touch more to the low teens, while the direction had started the long veer (clockwise rotation) to the right, that will eventually end (the other side of the Doldrums) in the south-east trade winds. The devil as always is in the details.
So, a couple of other things have changed, well, maybe three – no, make that four - boots are being traded for shoes on board. The second is that the leaders have started the course change towards the south. As the wind shifted towards the east, PUMA and Ericsson both let the wind angle tighten to about 110 degrees.
Then, as the wind continued to shift, they altered course to go with it, to end up sailing south-east – not far from the course to the scoring gate, which is currently 155 degrees (BRG_WPT). But PUMA went just a touch further with the course change than Ericsson 4, steering a little more south, so that there is now just over 25 miles between them, east to west.
The third thing is that the lead pair has poured on the mileage since yesterday – in 24 hours they’ve gained 55+ miles on each of the three boats behind them. I think this is partly boat speed, and partly the hand dealt by the weather, which at the moment is favouring the leaders. The latest analysis from Matt Sanders, Assistant Race Forecaster, describes how the fleet has been riding south on a wave of solid breeze, driven by a combination of high pressure dropping south behind them, and a cold front ahead of them. The high pressure is particularly visible, growing and drifting south-east and then east, if you click through the forecasts on the Race Viewer.
Bowman David Vera climbing up the sail to change a sheet, on leg 5 of the Volvo Ocean Race. Image copyright Gabriele Olivo/Telefonica Blue/Volvo Ocean Race.
Initially, this was great for the boats behind, the late-starters - Ericsson 3 and Telefonica Blue - as they were pushed down to the leaders on the new south-going breeze. But since then, the trailing boats have been closer to the centre of the high pressure, and consequently in a little bit less wind – and they have had to watch the leaders ease away from them. The squeeze box is back – always a feature of these north-south legs, where the fleet is crossing from one climate zone to another.
Green Dragon is aiming for an eastern transition of The Doldrums
And that brings us to the fourth thing - the fate of Green Dragon’s play to the east. For the next 24 hours the best breeze is to the west, as they transition from the northerly, into the north-east trade winds. There is a problematic area of light winds off to the east.
Unfortunately (life wasn’t meant to be easy) as we’ve discussed ad nauseam, the long-term gains ought to be to the east. It’s a question of balancing likely short-term gains to the west, with possible long-term gains to the east – and assessing each of those probabilities. And that’s the really hard part - as Ian Walker says - the forecast doesn’t go far enough ahead to allow them even the usual level of uncertainty. The seven-day forecast still doesn’t reach the south-east trade winds.
Walker did acknowledge that they were up against the fastest boats in the fleet, but while they were aiming for an eastern transition of the Doldrums relative to the others, they still didn’t intend to end up quite so far north. And after hearing that yesterday afternoon, it’s no surprise to see that the Dragon has spent the last 24 hours folding her hand, and falling into line behind the leading trio.
And there is still some interesting leverage around – Green Dragon is 120 miles east of Telefonica Blue, at about the same latitude. And as we mentioned before, Ericsson 4 and PUMA are spread 25 miles east to west, at the same latitude. So, we should get to see which side is faster.
I’ve dug up the seven day forecast, to have a quick look ahead, and – for what it’s worth - the transition through the Doldrums anywhere west of the Solomon Islands looks pretty ugly. So I think the boats will be targeting the eastern tip of this island chain to exit into the south-east trades. And that should give them a fast wind angle down to New Zealand, so long as they don’t get tangled up with Vanuatu or New Caledonia - the geography lesson continues...
Volvo Ocean Race
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment