Leg 8 Strategic Review Part 3 – How they did it...

MAPFRE’s dramatic win in Leg 8 was the result of a quite extraordinary comeback – almost 50nm behind with 36 hours to go, they had been in fifth place for most of the leg and struggling with the power systems that control the keel position for several days.

May 09, 2018 14:55 UTC

It all came good for them in the final three hundred miles to the finish at Newport, RI however, as the fleet hit a series of weather transitions.

Transitions
We’ve said all along that managing the transitions from one climate zone to another is the key to winning this race. The finish of Leg 8 was another example of just that, as the fleet rounded the western side of the Azores High and ran smack into a low pressure starting its run across the Atlantic in the Westerly Storm Track. It upended the fleet and the rankings, and transformed the overall leaderboard.

The earth’s oceanic climate zones lie in distinct bands, horizontally and looping the globe, running out from the Equator to the Poles in a mirror image. Racing north from Brazil to Newport in Leg 8 (full preview here) the fleet must transition several of these; 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. It was the last that caused all the trouble for long-term leader Team Brunel.

When we left them on the 1st May at the end of the last Strategic Review the fleet had just cleared the Doldrums, and were set to spend several days on starboard tack powering north through the trade winds and then going around the Azores High. Let’s pick it up there.

Doldrums exit
If we check out Image 1 from 14:00UTC on the 1st May we can see that the big winner as the fleet exited the Doldrums was Team Brunel (yellow). Dongfeng Race Team (red) had moved up into second place, ten miles behind the leader, after taking a westerly route through the Doldrums. Turn the Tide on Plastic (light blue) were in third with a 14nm deficit to the leader, and Vestas 11th Hour Racing (orange) was fourth 32nm behind.

©Geovoile - Image 1 (Click for larger image)

MAPFRE (white) took an eastern route into the Doldrums, and ended up 65nm behind the leg leader – the third bad Doldrums crossing for the team, who just didn’t seem to be able to line up the requisite luck that any strategy requires in this most inconsistent part of the sailing world... but what goes around comes around. Team AkzoNobel (purple) were back in sixth 84nm off the lead with Team Sun Hung Kai / Scallywag (grey) 164nm behind.

Trade winds entry
If we now check out Image 2, also from 14:00UTC on the 1st May but zoomed out and with the predicted optimum route for each boat added (the dashed lines), we can see that the strategy was very simple for the next week, with the Azores or Bermuda High set to dominate the North Atlantic.

©Geovoile - Image 2 (Click for larger image)

Azores High
If we check out Image 3 from 02:00UTC on the 7th May we can see that the predictions turned out to be remarkably accurate, as the fleet sailed north-west through the trade winds and around the western side of the High. The fleet’s wind direction slowly shifted from a north-easterly trade wind, to the easterly that’s flowing around the bottom of the high, and then the south-easterly, southerly and south-westerly in quite quick succession as they got to the west of the north-south centerline of the high.

©Geovoile - Image 3 (Click for larger image)

The gybe
If we have a look at Image 4 from 21:00UTC on the 6th May, we can see that there was a very solid consensus on the moment to gybe. The boats that had taken a more easterly lane into the gybe – particularly Vestas 11th Hour Racing and Team AkzoNobel – for the most part took a more easterly lane out of it.

©Geovoile - Image 4 (Click for larger image)

It was the age-old conundrum of balancing a shorter distance travelled (by being to the east), against a lighter wind (also to be found to the east, closer to the centre of the high). It seemed that west was best on this occasion, as Team Brunel skipper, Bouwe Bekking explained after the gybe:

All the forecasts we had said that being west would be the way to go in the long run.

Also that way we kept basic sailing rule number one in place – stay in between the finish and your opponent. Slowly but surely it started paying off and we started edging out and they are now just over eight miles dead upwind (behind) of us.

I am sure they are kicking themselves, as 24 hours ago they were more west than us. We matched last night two gybes against them, just to keep it simple and not to let them off the hook.

No change
The really remarkable thing is how little the standings had changed to this point, compared to Image 2 from five days earlier. Dongfeng Race Team were still ten miles behind Team Brunel, with Vestas 11th Hour Racing up to third, now 34nm behind rather than 32nm...

The loser, as so often in these tests of raw speed was Turn the Tide on Plastic, who saw all their good strategic work earlier in the leg unravel as they slipped back to fourth by losing 28nm.

The drag race winner was once again MAPFRE, who had pulled back 17nm on the leader — a pretty solid performance considering they were having power problems with their keel control. Behind them Team AkzoNobel had lost four miles to the leader, and the Scallywags just a single mile over the five days of sailing.

All change
These tiny percentage differences in performance were about to come crashing to a halt and be replaced by an altogether more dynamic, not to say chaotic situation. If we have a look at Image 5 from 03:00UTC on the 7th May, we can see why.

©Geovoile - Image 5 (Click for larger image)

The fleet were done with the Azores High, and were now sailing in a strong south-westerly wind from a low pressure system that had formed in front of them, and was now moving quickly to the north-east. The low pressure meant that they were back in the Westerly Storm Track – last seen as they exited the Southern Ocean.

More high pressure
The movement of the low pressure would sweep a cold front across the fleet. Normally this would see a transition to a north-westerly breeze, and perhaps a small drop in wind speed. But the rapid movement of the low meant that a bubble of weak high pressure was all that was behind the front, with very little wind.

Things now started to happen quickly. In Image 5 the fleet had 25-35 knots of wind speed from the south-southwest. In Image 6 from 10:00UTC on the 7th May, just seven hours later, everyone (except the Scallywags who were still in the breeze from the low) had a very light – 3-6 knot – north to north-easterly wind. The finish line was now two hundred miles upwind in very light air: cue the restart.

©Geovoile - Image 6 (Click for larger image)

Compression / restart
The leaders hit the transition from fast, windy downwind sailing to slow, light air upwind conditions first, and that compressed the fleet back together. It had also spread them out as the teams passed through the front at different places and at different times, and found different conditions on the other side of it.

Those that chose, or were forced to go north did well, as the next line of breeze was a northerly that arrived in a roughly east-west line as we can see in Image 7 from 13:00 on the 7th May. The original low pressure was a lot bigger now, centered just south of Newfoundland and already on its way across the Atlantic, and the northerly was created as the anti-clockwise circulation expanded around the low.

©Geovoile - Image 7 (Click for larger image)

Team Brunel had extended their lead over Dongfeng Race Team slightly, but MAPFRE had punched all the way back up to third, just five miles behind their rivals for the overall win – Dongfeng Race Team.

North-easterly
The northerly wind shifted to a north-easterly soon afterwards, as another small low pressure started to form south-east of Newport. We can see in Image 8 from 21:30UTC on the 7th May that this shift helped the boats to the east and/or behind. It turned it from an upwind leg, to a straight-line drag race.

©Geovoile - Image 8 (Click for larger image)

In particular, Dongfeng Race Team, MAPFRE and Vestas 11th Hour Racing gained on the leader, Team Brunel because they could sail a more open, faster wind angle towards the finish from their more easterly position. (The geometry of the rotation – as the windshift allowed them to turn and point at the finish – also meant the lead was cut).

Team Brunel obviously saw the danger of having this chasing pack to the east, and spent a fair bit of their lead tacking across to try to close the leverage (separation measured at right angles to the course to the finish) before the shift arrived; unfortunately it was too little too late. The westerly lane that had paid so nicely as they rounded the high, was now costing them the lead as they hit the lows of the westerly storm track.

Lead change
The wind continued to veer, or rotate clockwise, and in Image 9 from 02:00UTC on the 8th May we can see that the fleet had an easterly by the time they closed to 40nm from the finish line. The leading three boats had converged and closed out the east-west leverage. Dongfeng Race Team were now just over a mile ahead of Team Brunel. MAPFRE were another four and half miles further back.

©Geovoile - Image 9 (Click for larger image)

It’s worth just zooming out for a moment, to see how complex and unpredictable the overall weather situation had become by this stage. In Image 10 from 02:30UTC on the 8th May, we can see that the original low pressure was now a huge system just to the east of Newfoundland. Behind it we have an area of high pressure – with two weak centers – over Novia Scotia. And to the south of that, along the frontal line trailing the big low pressure system, there was at least one and maybe two more lows forming...

©Geovoile - Image 10 (Click for larger image)

Back to the high
The first problem for the race fleet was that the finish line was on the Rhode Island coast, and under the influence of the Novia Scotia high pressure. The winds were light, and while they were generally easterly, there was going to be a high level of variability.

The second problem was that they had to go around an exclusion zone (EZ) set up south of Newport which created a penultimate leg to the west, before they cut back to the north-east around Brenton Point to the line at Fort Adams State Park. The westerly section was always going to be tough in a light easterly breeze.

Dongfeng Race Team led around the corner of the EZ as we can see in Image 11 from 04:30UTC on the 8th May. The fleet continued to compress as the leaders continued to lead into lighter and lighter winds: 2.8 knots for Dongfeng, versus 7.8 knots for MAPFRE behind them.

Around the EZ
The two leaders found a little bit of breeze after they got around the corner of the EZ and were just about making course to Brenton Point. Then they hit another light patch, and were eventually forced to gybe back to the south, as we can see in Image 12 from 06:00UTC on the 8th May. MAPFRE had held better breeze around the corner of the EZ, and the lead was cut once again.

An hour and a half later, in Image 13 from 07:30UTC on the 8th May, we can see that – after an extended gybing duel in a light north-easterly – Team Brunel and then MAPFRE had gone past Dongfeng Race Team. While Vestas 11th Hour Racing had managed to roll with the breeze all the way from the corner of the EZ on starboard, saving all the maneuvers and closing their deficit to the leader to just two and a half miles.

The pressure in the cooker was rising.

Home straight
By 08:00UTC in Image 14, the leaders had struggled around the mark off Brenton Point and turned right up into Narragansett Bay. It was now a four-way battle for the win, with Team Brunel leading MAPFRE by 0.2nm, then Dongfeng Race Team 0.1nm behind them, and Vestas 11th Hour Racing just half a mile further back.

The wind speed was under a couple of knots for all of them and to pile on the agony, the ebb tide was just starting to run out of Narragansett Bay, giving them six or seven hours to battle against anything up to a knot of adverse current.

Final test
We can see in Image 15 from 09:30UTC the desperate conditions of this final test. Team Brunel and MAPFRE have escaped inside the bay, and were on the beach trying to find some relief from the current. Dongfeng Race Team and Vestas 11th Hour Racing were going backwards in the current, struggling to make any ground to the north towards Fort Adams and the finish line, and all the while, Turn the Tide and Team AkzoNobel were closing the gap... now just a couple of miles behind them.

Across the line
In Image 16 from 11:00UTC we can see that MAPFRE found a last gasp of breeze to get past Team Brunel after short tacking up the beach to the line. They crossed at 10:44:29UTC with the Dutch just 1min and 1sec behind them.

Vestas 11th Hour Racing escaped the clutches of Dongfeng Race Team by going up the western, Jamestown side of the channel... a little local knowledge coming into play there. The home town team finished on the podium with a third place a little under fifteen minutes after MAPFRE, with Dongfeng Race Team following in another 25 minutes after Vestas 11th Hour Racing.

The line-up was finally closed out with Team AkzoNobel in fifth at 12:21:22UTC; Turn the Tide on Plastic finished sixth at 12:24:14UTC, receiving scant reward for all the great work earlier in the leg. And the Scallywags concluded Leg 8 at 13:56:52UTC on the 8th May.

Consequences
I’m sure I don’t have to point out the consequences of the turnover in the last 36 hours of this leg. After staring at a three point overall deficit to Dongfeng Race Team for most of Leg 8, MAPFRE now find themselves with a three point overall lead.

There are three legs to go, and it’s nothing if not wide open with Leg 9 – the classic west-to-east transatlantic – a double pointer. I’ll be back here right after the restart to look at how the fleet will tackle the complex mix of fast moving low pressure systems, ice, fog and the Gulf Stream – you can read the preview here.