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News / Volvo Ocean Race - Leg 4 Strategic Review Part 2 – Hot toil in th...
Volvo Ocean Race - Leg 4 Strategic Review Part 2 – Hot toil in the Doldrums

Volvo Ocean Race - Leg 4 Strategic Review Part 2 – Hot toil in the Doldrums

January 11, 2018 - 19:00 UTC - Leg 4

Mark Chisnell evaluates the route through the trickiest patch of the race.

 

It’s been a hot, slow and psychologically tough week for the Volvo Ocean Race crews, ensnared in the most prolonged Doldrums crossing I can remember in the modern era. It’s taken three and a half days to get clear of the brambles and even now, there could be one more wobble before they settle into the trade winds.

 

The toughest Climate Zone

 

Leg 4 races from south to north, from Melbourne to Hong Kong, and crosses several climate zones as it does so. The full version of this story is in the Leg 4 Preview. If you’re short on time then just know that 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.

 

The Doldrums is the colloquial name for the rather less catchy Intertropical Convergence Zone or ITCZ. It lies at the centre of these ‘mirrored’ climate zones, in a band along the Equator, the hottest part of the planet. All that heating causes the hot air to rise, creating the classic seascape of clouds and thunderstorms that define the Doldrums. 

 

The rising air from the equator needs to be replaced, sucking air in from either side and it’s this movement that we call the trade winds – blowing from the north-east in the northern hemisphere and the south-east in the southern hemisphere to converge at the Doldrums.

 

When we left the fleet in the previous Strategic Review they had a couple of days of relatively easy sailing in the south-east trade winds ahead of them. They were closing fast on the Doldrums though, and the forecast had the ITCZ as wide and deep as the Grand Canyon. It looked ugly, and it was.

 

The set-up

 

Check out Image 1 from 21:00UTC on the 7th January – Sunday evening UTC, or Monday morning local time for the boats. The prediction was for the fleet to hit the main ITCZ Sunday evening, not long after rounding Santa Ana island. Ahead of them was up to a thousand miles of light winds and clouds.
 


©Geovoile - Image 1

 

The route to Hong Kong was to the north-west, but the fastest way to the north-east trades on the other side of the canyon of light air was due north. Everything indicated that the skippers should try to get north, and stay to the east of the rest of the fleet if they could... that was the set-up, let’s see what happened next.

 

Two easy days

 

In Image 2 we can see the fleet where we left them at 13:30UTC on the 5th January. The front four were in a relatively tight bunch, led by Dongfeng Race Team (red) and Team AkzoNobel (purple). MAPFRE (white) led the chase with Vestas 11th Hour Racing (orange) on their heels and then a more distant Turn the Tide on Plastic (light blue), Team Brunel (yellow) and Team Sun Hung kai / Scallywag (grey).
 


©Geovoile - Image 2

 

If we fast forward through the next couple of days to Image 3 at 01:00UTC on the 7th December we can see the moment when the leaders hit the first of the light air and the fleet started to compress. Dongfeng has just 10 knots of wind speed, Team AkzoNobel 12.5 knots – the rest of the fleet are hammering into them and closing the gap at pace with 17-19 knots of wind. And so it began.
 


©Geovoile - Image 3

 

This initial slowdown could have been due to the South Pacific Convergence Zone – another area of convergent winds and part of the wider ITCZ. I don’t want to get too deep in the meteorological weeds though... The important point for the fleet was that on this occasion the wind filled back in relatively quickly and painlessly.

 

By Image 4 at 20:30UTC on the 7th January Dongfeng had re-extended back into a decent lead, with the only major change being that MAPFRE had slipped past Team AkzoNobel to take second place.
 


©Geovoile - Image 4

 

Santa Ana

 

In the previous Strategic Review we thought that Santa Ana at the eastern tip of San Cristobal Island might be an important turning point. The fleet had to leave the island to port, a waypoint that would keep them to the east of the rest of the Solomon Islands. In the end, it turned out not to matter.

 

We can see in Image 4 that the fleet arrived at the tip of the island chain in the early morning local time (the Solomon Islands are +11hours relative to UTC) and there was plenty of gradient wind. Everyone went around Santa Ana with a solid 14-16 knots.

 

A grinding halt

 

The second grinding halt came the following morning at 05:00UTC on the 8th January, as we see in Image 5. Dongfeng hit the wall, MAPFRE, Vestas 11th Hour Racing and Team AkzoNobel ran into the back of them and in no time at all there was just 2.4 miles from the leader to fourth place.
 


©Geovoile - Image 5

 

This time there was no quick relief, the compression continued and by 19:30UTC on the same day, 8th January in Image 6 the main pack had turned inside out, with Vestas 11th Racing now leading from Turn the Tide on Plastic and Team AkzoNobel, and Dongfeng Race Team and MAPFRE back in fourth and fifth. Team Brunel were now latching onto the back of the pack, just ten miles off the lead. It was a full re-start.
 


©Geovoile - Image 6

 

Doldrums strategy

 

It’s one thing to have a strategy in the Doldrums, another to execute it. There was a wide consensus on the plan – go due north. The new breeze was to the north, and while Hong Kong was north-west, the fastest way to get there was to get into the new breeze, get moving fast and then start aiming at the target.

 

One impact of this was that the leaderboard didn’t reflect the situation on the water during the Doldrums crossing. It was measuring and ranking the fleet on how close they were to Hong Kong to the north-west, when what mattered was how far north a boat had managed to get. Fortunately, it’s relatively easy to see how they were all doing, since north is at the top of the page...

 

So much for the plan, how do you execute it with no wind?

 

It’s not normally like this...

 

It’s been clear from the blogs and reports coming off the boat that this has been a particularly tough Doldrums. While light air is always a part of the picture, there is usually a fair amount of cloud activity and under the clouds there is usually wind and often rain.

 

The technique to sailing through the Doldrums is watching these rain clouds on the radar, and trying to position the boat to use the wind from one to get to the next. It’s very hard to do at the best of times, and there’s a fair bit of luck involved, as well as a whole lot of skill and experience.
 


©Geovoile - Image 7

 

This has not been the best of times, it’s been the worst and it appears that there has been much less cloud activity than normal, leaving just the light winds. The height of the frustration might well be encapsulated in Image 7 from 05:00UTC on the 10th January. The fleet are crawling north, four of the seven boats have just two knots of wind at the masthead.

 

Leverage

 

The fleet had split with a fair amount of east to west distance. I’ve used the measuring device to show that there was almost 24 miles of leverage (distance between boats measured perpendicular to their course to the destination) between Turn the Tide on Plastic and the rest of the main pack to the east. It looked like the west was working, 24 hours earlier, Turn the Tide on Plastic had been four miles south of the leader of that pack.

 

Desperate

 

It was at this point that Xabi Fernandez, the skipper aboard the overall leader MAPFRE wrote, “Desperation is probably the only word to describe how we feel sailing through these Doldrums.” Indeed, and the ball hadn’t stopped bouncing.
 


©Geovoile - Image 8

 

Five hours and change later and in Image 8 from 10:30UTC on the 10th January we can see that Vestas 11th Hour Racing and Dongfeng Race Team have doubled down on their efforts to get north, managing to eke out a six mile advantage in this direction, shown by the measuring stick. In the middle are MAPFRE, Team AkzoNobel and Turn the Tide on Plastic, while Team Brunel and Team Sun Hung Kai / Scallywag have gone for broke out west. No one has much wind.

 

Relief arrives

 

It had to end eventually and it did – half an hour later the wind started to fill, probably from a local cloud that suddenly powered up the boats in the middle of the fleet. Check out Image 9 at 11:00UTC on the 10th January. MAPFRE and Team AkzoNobel have 12 knots of wind speed, everyone else still has just 3-6 knots. The new breeze is from the east / south-east, so this isn’t the north-east trade winds yet, but they’re coming...
 


©Geovoile - Image 9

 

A couple of hours later at 13:30UTC on the 10th January in Image 10, and the breeze has filled through the fleet, with most of them now getting an easterly of 11-15 knots. It was strongest to the north with all that effort finally paying off for Vestas 11th Hour Racing and Dongfeng Race Team.
 


©Geovoile - Image 10

 

MAPFRE and Team AkzoNobel benefitted from being in the right place at the right time when that new breeze first hit, and they were able to start to close down the gap to Vestas 11th Hour Racing and Dongfeng Racing – Team AkzoNobel doing it more successfully than MAPFRE.

 

Wind Shift

 

It wasn’t quite over though, soon after the breeze got turned on its head again, with everyone getting a big shift to the south. In Image 11 from 15:30UTC on the 10th January, we can see the southerly arriving, although the wind strength stayed solid, at least in the north. Everyone got onto port gybe in the southerly wind, but they must have known that it wasn’t over yet, as a southerly wind is clearly not the north-east trade winds...
 


©Geovoile - Image 11

 

The final shift

 

The breeze started to shift anti-clockwise (or back) round towards the south-east about 20:00UTC on the 10th January. The whole fleet flopped onto starboard gybe, as we can see in Image 12 from 21:30 on the 10th January – presumably expecting the new breeze to be the north-easterly, and figuring it was smart to head that way towards it.
 


©Geovoile - Image 12

 

The lead pack have huddled back together like puppies looking for warmth, with just five miles separating Vestas 11th Hour Racing, Team AkzoNobel, Dongfeng Racing Team and MAPFRE. It’s the same four boats that led us into the Doldrums, but shuffled. 

 

Vestas 11th Hour Racing were the winners here, going from a solid fourth place 12 miles behind the leader before the nightmare started, and now leading out of the Doldrums. Fighting to get north, and staying east of the rest of the fleet paid, in the end...

 

They (don’t quite) think it’s over...

 

Overnight the wind shifted into the east and then back to the south-east, and Image 13 brings us right up to date at 13:00UTC today, the 11th January. The wind shift is visible in the curved track of the boats – they turned left as the wind went to the east, and then turned back right to head north again as the wind returned to the south-east.
 


©Geovoile - Image 13

 

They were sailing a true wind angle of 120 – it could be more like 130 or 135, so if they wanted to they could be sailing a course closer to Hong Kong. They’re probably not completely confident that they are out of the Doldrums, but there’s another reason for wanting to get a bit further north before they turn and go for Hong Kong.

 

The leaders – Vestas 11th Hour Racing, Dongfeng Race Team and Team AkzoNobel are almost 30 miles further north than the pair chasing them, MAPFRE and Turn the Tide on Plastic – although they are just 3 miles close to Hong Kong. It will be interesting to see what sort of lead that converts into once they all make the turn – my money would be on the leader’s advantage growing on the leaderboard steadily through the next 24 hours.

 

Going forward

 

There may be one more wobble, but broadly we know that we’re expecting the breeze to strengthen, and rotate anti-clockwise to the left over the next 24 hours. In Image 14 we can see where the fleet is predicted to be by 13:00 on the 13th January, two days from now.
 


©Geovoile - Image 14

 

We can see the north-east trades blowing strongly in the right hand side of the picture. At the very top underneath the title the sub-tropical high is just about visible, and in the top left, the north-east monsoon is currently blowing dogs off chains.

 

In the bottom centre and left of the picture is another area of high pressure that they need to stay well clear of – this is partly the reason for the fleet holding a northerly course for longer than they might otherwise. To the east the wind is stronger, and with a better direction providing a faster sailing angle.

 

The downside of holding to the east now is that they may eventually have to gybe to get around the top of the Philippines. In Image 15 we are looking at 14:30 on the 16th January, right about the moment when the predicted optimal route calculation thinks the fleet should start to gybe.
 


©Geovoile - Image 15

 

It’s a long way ahead, but by the 17th January a small high pressure system is predicted to form to the north-east of the Philippines, and that could interrupt service from the north-east Monsoon. We could end up with the fleet running downwind in light air on a part of the race course where everyone expected a screaming reach in 35+ knots. There may yet be more golf in this hole, I will be back should it come to pass...

 

Text by Mark Chisnell

 

www.volvooceanrace.com

Fonte: volvooceanrace.com
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