Leg 8 Strategic Review Part 2 – Through the Doldrums


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We are just into the second week of Leg 8 and the fleet have already cleared the Doldrums, crossed the Equator and are back into the Northern Hemisphere and racing north in strong trade winds. This isn’t the home straight, but you can just about see it from here.

© Sam Greenfield/Volvo Ocean Race

Turn the Tide on Plastic made all the running for the first few days – after they grabbed the lead at the Cabo Frio Exclusion Zone, but finally ceded control to Vestas 11th Hour Racing and Dongfeng Race Team. Those teams then lost it in the Doldrums to the big winner right now – Team Brunel. Lots of changes, so let’s dig in.

South to north

This is a south to north leg, and so the transitions through the climate zones will be a big part of winning and losing. In case you’ve missed it... the earth’s oceanic climate features distinct bands, lying horizontally and looping the globe, running out from the Equator to the Poles in a mirror image.

This time around for Leg 8 (full preview here), we are racing around the St Helena High, through the trade winds, across the Doldrums, back into the trade winds, around the Bermuda (or Azores) High and finally into the Westerly Storm Track to finish in Newport.

And the fleet have already ticked off the first three from that list, clearing the St Helena High, into the south-east trade winds and now, as of this morning out of the Doldrums and into the north-east trades – plenty of action and lots of opportunities on those transitions.

Pick a lane

We left the fleet at 13:00UTC on the 25th April as you see them in Image 1. The fleet were sailing upwind in a north-easterly wind past the oil field exclusion zone (EZ - visible as the red hashed area in Image 1) and we expected everyone to tack very soon, as the predicted optimal route was suggesting. There were two reasons, firstly it appeared that no one could get past the EZ without another tack, and secondly the wind looked lighter inshore, near to the EZ.

©Geovoile - Image 1 (Click for larger image) 

Sure enough the whole fleet tacked and headed offshore soon after, as we can see in Image 2 from midnight UTC on the 25th April. Once they were on port tack, it was soon time to think about picking a lane to go back north – east or west of the competition?

©Geovoile - Image 2 (Click for larger image) 

East or west?

Team Sun Hung Kai / Scallywag (grey) were the first to tack back to starboard and resume the trek northwards, setting up in a very westerly position relative to the rest of the fleet. Team Brunel (yellow) were next, then a pack with team AkzoNobel (purple), Vestas 11th Hour Racing (orange), MAPFRE (white) and Dongfeng Race Team (red) – the overall leaders still glued together. Finally, we had Turn the Tide on Plastic (light blue) taking the most easterly position – a repeat of their strategy approaching Cabo Frio and the EZ.

The elements of the decision were very similar to those that played out to Turn the Tide's advantage in the last Strategic Review. There was less wind on the coast, and the wind was predicted to shift as they headed north to allow them to eventually sail in a straight line and stop tacking. So, picking the right moment to settle on starboard tack was critical.

Any boat that went too far east would sail extra miles and lose, but... if they didn’t go far enough east at this point, they would pay later – perhaps even doing time on port tack in a much less optimal wind speed and direction. The latter was exactly what most of the fleet had done approaching the EZ, allowing Turn the Tide to grab the lead. It was hardly surprising then, that having gained in the east the first time around, Dee Caffari and her navigator Nicolas Lunven should once again set up as the most easterly boat.

Payback

If we check out Image 3 from 09:30UTC on the 27th April we can see that things once again worked out very nicely for Turn the Tide on Plastic. They had a tough night prior to this with a lot of cloud activity and at some points the fleet even saw a northerly wind direction. It all came good by this moment on Friday morning; the leverage (separation of the boats perpendicular to the course) had more or less gone and they had a solid lead of 12 miles over Vestas 11th Hour Racing, and another ten over third placed Dongfeng.

©Geovoile - Image 3 (Click for larger image) 

The east had once again been the best option. This time around no one had had to go back to port tack, but the westerly boats had ended up sailing narrower, slower wind angles for long enough that Turn the Tide on Plastic had popped back out in front.

The wind was now round into the south-east for the leaders, and they were finally seeing some fast and reasonably settled trade wind sailing. Transition one, around the St Helena High and into the trade winds: tick. Winner: Turn the Tide on Plastic.

Recife

Next up was the corner at Recife, the most easterly point of mainland Brazil sticking out into the South Atlantic. The accumulated race wisdom suggests that you have to stay within 10 miles of the coast at Recife, or stand further off than 100 miles. On this occasion it looked like it really had to be the former, as it would place the boats in the right spot for the Doldrums crossing. The early predictions were for the Doldrums to be a lot narrower to the west, and almost non-existent on the coast of South America.

We can see in Image 4 from 19:00UTC on the 28th April that this was how it played out, with everyone choosing to stay close to the coast at Recife. Turn the Tide on Plastic had held the lead, although Vestas 11th Hour Racing and Dongfeng Race Team have both more or less halved the advantage in the drag race north. The whole fleet fell into line in the south-east trade winds to file past Recife, and the reason was as we expected – they all wanted to transit the upcoming Doldrums to the west.

©Geovoile - Image 4 (Click for larger image) 

Setting up for the Doldrums

If we move onto Image 5 from 05:00UTC on the 29th April, we can see just how favourable it looked to the west. The dark blue of the windless Doldrums thins significantly right-to-left, or east-to-west on the image, and disappears completely at the edge of the picture, close to South America.

©Geovoile - Image 5 (Click for larger image) 

The size and position of the Doldrums varies enormously – driven by the energy and position of the climate zones to the north and south. The fleet were treated to an easy transition going the other way on Leg 2, then two shockingly difficult transitions in the Pacific. And now the Atlantic was treating them kindly again, if they could get far enough west.

Go west...

The gybe-fest to stay west of everyone else had already begun at the time of Image 5. The fleet were now running up the coast of South America in a gorgeous 13-16 knot south-easterly trade wind. There are many worse ways to spend the day, and few that are better.

It was soon time to pick a lane and – reliably – Team Sun Hung Kai / Scallywag were the first to peel off and take a stance as we can see in Image 6 from 16:30UTC on the 29th April. They headed offshore first, with the rest of the fleet sticking with the coast for another three hours before MAPFRE and team AkzoNobel settled on starboard to go north as well.

©Geovoile - Image 6 (Click for larger image) 

The lead group of Turn the Tide on Plastic, Vestas 11th Hour Racing and Team Brunel – all within three miles of each other – went offshore about the same time, but their lead meant that they did it from a more westerly position.

Dongfeng Race Team were the last to go, taking one last hit of coastal air before joining the charge north. It was interesting to see that the two overall leaders had now got this far apart – largely because MAPFRE had slipped back out of AIS range and Dongfeng Race Team were unable to cover them... even if they had wanted to.


Doldrums

The fleet started to hit the funky stuff early on Monday morning, as we can see in Image 7 from 04:00UTC, 30th April. The windspeeds dropped under ten knots, and the variation in wind direction was 110 degrees – it was game on and the end of transition 2; out of the trade winds and into the Doldrums. Winner: Vestas 11th Hour Racing.

©Geovoile - Image 7 (Click for larger image) 

It’s worth noting that there was quite significant leverage between the two overall leaders as they headed into this final round of Doldrums roulette for this edition of the race. They were about 60nm apart with Dongfeng Race Team to the west, and MAPFRE to the east, so there was plenty at stake with just a point between these two for the overall lead.

Progress was slow through most of yesterday; in Image 8 we can see the fleet at 18:30UTC yesterday evening. No one has more than seven knots of wind, with MAPFRE out to the east in just two knots... not looking good for the Spanish challenge at this point, particularly as Dongfeng was still tight with the lead pack.

©Geovoile - Image 8 (Click for larger image) 

Unfortunately, shortly after this there were some issues with Live updating of the tracker, so we don’t have much detail of what happened overnight – just the outcome in Image 9 from 14:00UTC today, 1st May.

©Geovoile - Image 9 (Click for larger image) 

New leader

The big winner in the third transition for this leg, out of the Doldrums and back into the trade winds has been Team Brunel. They managed to drop the other two boats in the lead pack – Turn the Tide on Plastic now 14nm behind, and Vestas 11th Hour Racing 32nm back. Dongfeng Race Team have held onto second place, ten miles behind the leader, so the west didn’t work out so bad for them.

MAPFRE have not had a happy time in the east, now 65nm behind the leg leader, and with plenty of work to do if they are not going to lose a lot of points on the overall leaderboard to Dongfeng Race Team. They have suffered in three out of four Doldrums crossings, and it wouldn’t be hard to make an argument that this one weather feature has been the significant factor in the overall lead.

Trade winds

The breeze had now gone round to a classic north-easterly trade wind and was blowing hard at 16-18knots. Speeds will be high and the deck will be plenty wet for a while. So long in fact, that if I zoom out and add the predicted optimum routes to the picture we get Image 10 from 14:00UTC today... and we can see that there’s not much more than one gybe between here and Newport, RI. It’s all going to be about speed for a while...

©Geovoile - Image 10 (Click for larger image) 

The tracker is in Live mode, so it won’t move the boats along the optimum track to show you, but we can see how the weather could play out. In Image 11 we have the boats in their current positions at 14:00UTC 1st May once more, with the optimum route plotted to Newport again, but this time the weather forecast for four days' time. This is about the moment when they will be making the gybe in the top left of the image.

©Geovoile - Image 11 (Click for larger image) 

Azores High

The Azores or Bermuda High will be dominating the North Atlantic, and the fleet will sail around the western side of it. Their wind direction will shift from a north-easterly trade wind, to the easterly that’s flowing around the bottom of the high, and then a south-easterly, southerly and south-westerly in quite quick succession as they get to the west of the north-south centerline of the high. Somewhere in that shift they will need to pick their moment to gybe and set up the approach to the finish.

I suspect that this decision will be relatively straightforward when it comes, as it looks like they then have at least a day of very fast sailing more or less straight at the finish line at a 90 degree true wind angle (beam reach). This one could be settled on raw boat speed from here...

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