? 2017-18赛季沃尔沃环球帆船赛- LEG3 Cape Town to Melbourne - 船赛 - 航海世界 狗万 角球_狗万代理_指南_狗万国内第一吗
2017-18赛季沃尔沃环球帆船赛- LEG3 Cape Town to Melbourne



Leg 3 Strategic Review - Close out


Text by Mark Chisnell


MAPFRE closed out a beautifully executed win of Leg 3 of the 2017-18 Volvo Ocean Race on Christmas Eve (UTC) – and I’m sure that someone, somewhere went for the ‘early Christmas present headline’ when reporting the achievements of Xabi Fernandez and his crew.?If this was a Christmas present, it’s one they bought for themselves, paying in sweat and effort to get this one across the line.


? jesus Renedo/Volvo Ocean Race


In the?last Strategic Review?we looked in some detail at the passing maneuver that gave the lead to the Spanish, so I won’t revisit that one here. Let’s pick it up where we left it, at midday UTC on the 21st December, a moment we can see in Image 1.


??Geovoile - Image 1


Away from the ice


MAPFRE were leading Dongfeng Race Team away from the last corner of the Exclusion Zone, a red line (literally red on the Race Tracker) put in place by officials to keep the fleet clear of Antarctic ice. They had been pinned against this for days, but had finally cleared the last corner and were now looking at a wide field of play for the final approach to Melbourne.


In the?Preview for Leg 3, I considered two options for the finish, the first was a storm moving north from the Westerly Storm Track and pushing them all the way across the line. The second was that high pressure would dominate over Melbourne, and make for a long slow endgame.?


Two end games


At the time of the last Strategic Review, we were expecting a bit of both. The weather forecast for the final few days of the leg had a low pressure system taking the leaders all the way across the finish line. And then the semi-static area of Subtropical High Pressure that normally sits to the north of the Westerly Storm Track was forecast to reassert itself, and make things painful for the backmarkers.


In Image 2 from 09:00UTC on the 24th December, we can see the weather prediction for the high to move back to the south-east, and block the route into Melbourne with light air.?This was about the time that MAPFRE and Dongfeng were predicted to finish, with Vestas 11th Hour Racing and Team Brunel also safely ahead of the worst of the high.


??Geovoile - Image 2


Caught by the high


The predicted routes showed that Team Sun Hung Kai/Scallywag and Turn the Tide on Plastic would not quite make it, and would have to deal with finishing in lighter conditions, while Team AkzoNobel were forecast to be badly slowed and eventually finish three days after the leaders.


If late, stay east


In strategic terms the main point we took away from this forecast was that the further down the fleet you were, the more dangerous it was to gybe early out of the Southern Ocean, and approach Melbourne from the west. The reason was that this was the direction that the high was pushing in from. However, the front of the fleet had a wide range of routing options open to them, and that mean that there were passing lanes. All right, that was the set-up, let’s see how it played out.


Big shift


In Image 3 from 22:30UTC on the 21st December we can see just after the moment when both MAPFRE and Dongfeng Race Team gybed and headed out of the Southern Ocean and towards Melbourne. The reason they went at the same time was a significant wind shift from the south-westerly direction it had been blowing, moving right (or veering) around the compass dial to the west.


??Geovoile - Image 3


This new wind direction meant that the port gybe was now giving them a significantly better VMC, or Velocity Made Good to the Course. In simple terms, the wind shift meant that port was now taking them towards the finish line much faster than starboard gybe. So they both got onto port.


The shift is visible in the wind flow lines in the image, it’s also visible in the significant course change that MAPFRE took towards the south just before the gybe, and finally, it’s visible in MAPFRE’s wind direction of 282 degrees. And it’s very significant that they have more of this wind shift than Dongfeng, who are reporting a wind direction of 265 degrees.?That wind direction is still advantaging the port gybe for Dongfeng, but not as much as it was for MAPFRE.


Stealthplay


To add a little spice to this moment, Dongfeng Race team notified the race committee that they wanted to go into their Stealthplay soon after the gybe. It meant their position was now hidden for three position reports, leaving them in Stealth until 19:00 UTC the following day.?So MAPFRE had no idea that they had gybed together as they were over 30 miles apart at this point and out of range of the tracking system they have onboard.


It must have been a pretty tense 24 hours aboard MAPFRE, but it all worked out just fine for them, as we can see in Image 4 from just after 19:00UTC on the 22nd December, the position report that ended Dongfeng’s Stealthplay, now 95 miles behind the leader, and a huge loss.


??Geovoile - Image 4


Private wind shift


The problem for Dongfeng was that they never quite managed to get as far into the wind shift as MAPFRE. I’ve taken the wind lines off this image because it makes the tracks of the boats more visible, and that’s what really tells the tale. After the gybe, the courses of the two boats diverged significantly, as Dongfeng sailed in the 265, and MAPFRE in the 280 – all of this was gains for MAPFRE.


The crew aboard Dongfeng were able to see their losses, and their first gybe back to the east was right after the 13:00UTC position report, as I have indicated on the image. They could see that they were bleeding miles, that MAPFRE had a better wind direction and they gybed to go looking for it. It seemed like MAPFRE had private access to that wind shift though, after the gybe back to port, the boats continued to diverge and Dongfeng to lose miles.


??Geovoile - Image 5


In Image 5 from 09:30UTC on the 23rd December, they had both gybed to starboard to head for Melbourne, and MAPFRE was still 97 miles in front, and positioned both ahead and to leeward of Dongfeng.?It was an unassailable position, even before Dongfeng announced that they had a problem with their port keel ram that had lost them miles, and might lose them more.


Attention turns


If the tension had gone out of the battle for the leg win, it immediately shifted to the rest of the podium. Vestas 11th Hour Racing, and Team Brunel had both followed the advice of the weather routing, and held onto the starboard gybe for a lot longer, to position themselves further to the east on the approach to Melbourne, and clear of the inbound high pressure.


By 20:00UTC on the 22nd December in Image 6, we can see that Vestas 11th Hour Racing have just gybed out of the south, soon after the 19:00UTC Position Report. They are very close with Team Brunel, the leaderboard says a couple of miles behind, although the image makes it look as though they will cross in front. And the pair have a deficit of around 140 miles to Dongfeng Racing.


??Geovoile - Image 6


More Stealth


By then Vestas 11th Hour Racing had played their Stealth card, so this was the last time they were visible on the Position Reports to Team Brunel for 24 hours – although they are close enough that they should have been able to see them on AIS or radar.


Vestas 11th Hour Racing subsequently gybed in front of Team Brunel, and then gybed again to settle on port and head north. Team Brunel followed them out of the south soon after, and may have had a problem because by midnight on the 22nd December, in Image 7, they were 20 miles behind Vestas. There’s nothing in the logs about any issues, and it’s hard to see that they would lose so much in a wind shift or with a wind speed difference when they were so close, so I can’t explain this loss readily...


??Geovoile - Image 7


East pays


Fortunately, what happened next is much clearer, the two pairs of boats MAPFRE / Dongfeng Racing and Vestas 11th Hour Racing / Team Brunel closed on each other. The former were coming from the west, the latter from the south and by Image 8, at 02:00UTC on the 24th December it was clear that with 300 miles to go, the easterly option had really paid for Vestas and Team Brunel.


??Geovoile - Image 8


At this moment, Vestas 11th Hour Racing was recorded as a couple of miles closer to Melbourne than Dongfeng, the Chinese boat having fallen into the influence of the lighter winds from the high pressure and suffered that issue with their keel. But even while they suffered from a lack of wind speed, the wind direction was in favour of Dongfeng.

Progressive shift


In Image 9 we can see the wind slowly shifting from a westerly (270 degrees) blowing from the low pressure system at the latitude of Hobart; to about a south-southwesterly (210 degrees) blowing around the eastern quadrant of the high into Port Phillip Bay and the finish at Melbourne.


??Geovoile - Image 9


Vestas 11th Hour Racing and Team Brunel were sailing from the 270 to the 210 on port gybe, which meant that the slow progressive shift had been steadily taking them away from the direct course to Melbourne – an effect that you can see in their curved tracks in Image 8, and in the differences between the wind directions in the table for the two pairs of boats.


MAPFRE and Dongfeng Racing had wind directions of 212 and 218 respectively and were pointing at Cape Otway, where they could gybe and head into Port Phillip Bay. At this moment, Vestas and Team Brunel had wind directions of 236 and 243 respectively, but as they slowly sailed into the wind that the lead pair had got, they lost ground.


So by 09:00UTC on the 24th in Image 10, MAPFRE was just 78 miles from the finish, with a 90 mile lead over Dongfeng, who had in turn crossed in front of Vestas by a comfortable 26 miles. Vestas Racing put an extra couple of gybes in to get directly in front of Team Brunel on the approach to Cape Otway, but also maintained a lead of just over 20 miles.?


??Geovoile - Image 10


All she wrote


And that was all she wrote – the rest was just solid tactics by each boat to maintain their advantage over the boat behind. MAPFRE arrived at 16:07 on the 24th, with Dongfeng coming second just over four hours later. Vestas 11th Hour Racing took the final place on the podium one hour 42 minutes later, with Team Brunel another hour and 44 minutes behind her.


It was close, but in the end there were no lead changes on the final approach – although I’m sure Dongfeng will be wondering what might have been if they had used their StealthPlay to carry on east, and take the route of Vestas 11th Hour Racing and Team Brunel. Vestas 11th Hour Racing gained about 90 miles on Dongfeng in the final approach, and that would have been enough to put Dongfeng right beside MAPFRE as they came into Port Phillip Bay – but hindsight is always 20/20 perfect....


And the rest


Behind the leaders, Turn the Tide on Plastic tracked Team Sun Hung Kai / Scallywag out of the Southern Ocean with a deficit of around 50 miles. They both took a more easterly option than the boats ahead but, as predicted, they still had to struggle through the high pressure ridge as it moved in to block the route to Melbourne.


The 50 mile lead collapsed to just over ten as they both struggled through the high pressure on Christmas Day – Image 11, from 05:30 on the 25th December. It’s still a pretty good lead though with a couple of hundred miles to go, especially as there was good breeze north of the high which Team Sun Hung Kai/Scallywag was able to lead into and extend once again. They finished fifth at 01:06UTC on the 26th December, with Turn the Tide on Plastic just under three hours behind.


??Geovoile - Image 11


It was every bit as bad for Team AkzoNobel as we feared in the previous Strategic Review. They paid a high price for the damage they did in the gybe in the Southern Ocean storm, having no good choices with the high pressure blocking their route to Melbourne. They finished on the 27th at 23:24UTC, over three days behind the leaders, as expected.?


Overall lead


Their second consecutive leg win, and on a double points scoring leg gives MAPFRE 29 points, and an enviable lead of six points over Dongfeng Race Team and Vestas 11th Hour Racing, who are now joint second on 23. These three have a big jump on the rest of the pack, with Team Brunel on 14, Team Sun Hung Kai/Scallywag on 11, AkzoNobel on 9 and Turn the Tide on Plastic on 6.


It looks like it’s MAPFRE’s race to lose at this point, but their wins have relied on being just that tiny bit smarter than Dongfeng Racing, and it’s not a given that they can keep this up for another six months. It may also play heavily on the MAPFRE team that they have been here before when, in 2011-12 as Telefónica they won the first three legs before being slowly overhauled by Groupama 4 – finally ending up fourth.


There have been lots of changes to the programme since then, and I think this is a stronger team now – but the differences are small, and they will need to keep it together all the way round to close out the overall win.


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