Vendée Tactics Briefing: Vendée Globe - fast lane for Boris in the South Atlantic?

After what felt like a very long phase in the Southern Ocean, the first boats in the Vendée Globe are now entering a completely different but no less decisive phase of the race as they round Cape Horn.

In the lead, a fierce tactical battle developed between Yannick Bestaven on board "Maître Coq", who passed the horn first and far out at sea, and Charlie Dalin on "Apivia", who initially chose a different course closer to the coast.

The main question facing skippers is how best to navigate around a high that is developing north of the Falkland Islands. It will slowly move eastwards towards the Saint Helena High over the next 72 hours.

Yannick Bestaven has opted for a more easterly route, which allows him to stay in a more exposed part of the South Atlantic, where the wind blows around the horn and strengthens in the process. In doing so, Bestaven is taking a not inconsiderable diversions. He apparently assumes that the high will shift to the east earlier and thus block the more direct, westerly route.

Charlie Dalin, who initially tried the inside course, also seems to have recognised the risk of running out of wind this morning. After two gybes, he has now moved onto Yannick Bestaven's course.

The danger of a route close to the coast lies on the one hand in the lee of the South American mountains and on the other hand in the proximity to the centre of the high. However, there is also a positive factor: the latest generation of foilers, including "Apivia", are very fast in flat water; they don't need much more than 12 knots of wind to take off. Thomas Ruyant, who passed the cape in third place and is probably trying his luck west of the Falklands, is obviously counting on this.

At the moment, the routings still suggest that Yannick Bestaven can maintain the lead. But it will only become clearer once the boats have rounded the east side of the high on Wednesday.

Behind the leaders there is now a considerable gap to the chasing group, which is between 600 and 700 nautical miles behind - including three boats with conventional centreboards such as "Omia Water Family", "Yes We Cam!" and "V&B" alongside foilers such as Boris Herrmann's "Seaexplorer - Yacht Club de Monaco".

As we have seen for weeks now, there were hardly any significant advantages for the modern hydrofoils in the Southern Ocean; sometimes they were even at a disadvantage - be it because of breakage or because they accelerated too much in the swell only to get stuck in the next wave. But once they have rounded Cape Horn, the conditions will change completely.

The Horn is so notorious for extreme conditions, as it is considered to be the deathbed of south polar lows. These lows have travelled thousands of miles to reach the Horn, building up huge waves along the way. As soon as skippers are east of this point, they are almost immediately transported to the birthplace of new weather systems - and into completely different, more complex conditions.

There are two main meteorological features in the South Atlantic that are relevant for the skippers of the Vendée Globe: High pressure areas such as the one north of the Falkland Islands that Yannick Bestaven and Charlie Dalin are currently dealing with, and the formation of lows along the South Atlantic Conversion Zone. These "young" systems and the land protection of the South American continent ensure that the sea remains comparatively moderate.

Boris Herrmann on board the "Seaexplorer - Yacht Club de Monaco", together with the other newer foiling Imocas in his group, will be looking for the opportunities that the South Atlantic offers him in these shallow water conditions. Throughout the Southern Ocean, he was only able to reach around 80 per cent of his maximum speed potential due to the swell. After passing Cape Horn, he should be able to get back to or close to 100 per cent of his polar data - and thus exploit his speed advantage over the non-foilers around him.

If you look at the weather situation for this group, high pressure will continue to dominate after the Cape. However, due to the time lag between them and the leaders, the high pressure will have already shifted, making an easterly route much more difficult, if not impossible, under room sheet conditions.

For Thomas Ruyant on "LinkedOut" and Damien Seguin on "Apicil", this could be the deciding factor for 3rd place in the Vendée Globe. If they sail upwind, they will both be on starboard bow for a long time, as already explained in relatively flat seas. These are ideal conditions for Ruyant, especially as he still has his fully intact foil on this bow (he had to shorten his port foil considerably with the flex to take the load off the structure, which had already cracked on the way south). It is therefore possible that he will be able to sneak past the core of the high while Damien Seguin is blocked.

All those who pass the cape after these two will be forced to sail upwind to the west of the high, which is not a great advantage for the foilers in this group. But towards Friday, a low will develop off the Brazilian coast, offering a new opportunity for Boris Herrmann and his rivals.

They can hold to the north-west and latch onto the western side of the low, which offers good south-westerly winds. However, as this system is young, it moves east very quickly while the fleet tries to head north. So the advantage will not last long.

At this point in the race, the transitions between the weather systems will be crucial - as will the optimum timing. Who can adapt to the changing conditions the fastest and keep their boat at optimum speed for the longest time?

Conditions in the southeast trade wind regime only become more stable around the 20th parallel. The skippers will probably reach this part of the South Atlantic around 14 January. This is where I think the foilers can make miles. From here, they have around 3000 nautical miles ahead of them in their optimum range - at 70 to 90 degrees wind angle, in flat seas. Compared to conventional boats, they then log 5, 6, even up to 8 knots more due to the higher righting moment of the hydrofoils and the smaller wetted area.

If Boris Herrmann succeeds in leaving the complicated weather systems of the deep South Atlantic cleanly and without falling far behind, he has a great chance of putting himself in a strong position for the final leg in the North Atlantic.