Wednesday, June 16, 2021

WHY ARE THE NEW IMOCA SLOWER THAN THE OLDER VOR 65, IN THE OCEAN RACE EUROPA?


VOR 65 Mirpuri Foundation
Many have said that the VOR 65 was outdated, too heavy, and they would expect the last generation of IMOCA, on foils,to leave the VOR 65 behind but very few would expect that on the Med leg between Valencia and Genova the differences were so big. 

Maybe the ones that had doubts start to believe that the hugely beamy Imoca hulls are only suited to a very small set of conditions, the ones you can find on the trade winds. Even in what regards downwind sailing and beam reaching the IMOCAS seem only to be faster over 20kt winds.
VOR 65 (drawing by Francois Chevalier)
Downwind with medium winds IMOCA and VOR 65 seem to have a very similar performance but upwind and in lighter wind the VOR 65 is much faster. For an overall use the VOR 65 is a faster boat, being the IMOCA only faster in a small set of conditions.

Of course the VOR65 has a crew more than two times bigger than the one of an IMOCA, but there is no reason for the running of a VOR 65 (and sails) to be adapted to be sailed by four, and I believe that if the four were top sailors, the boat would lose a bit in speed, but it would be still overall faster than a top IMOCA.

And if we look at the hull of the older VOR 70 Groupama, the faster of all VORs, we will see that it is even narrower that the VOR 65. The 65 is probably more adapted to trade wind sailing, but if we compare the sailing results in IRC offshore races (real time) we will see that the VOR 70, under several names, has been consistently faster than the VOR 65 and in IRC has won many big races.

IMOCA 11th Hour (drawing by Francois chevalier)
So, as I have been saying it makes no sense to use hulls with shapes derived from IMOCA on cruising boats, even less in performance cruising boats (in what regards sail performance), but what happens is precisely the opposite with designers claiming they are using on cruising sailboats faster hull shapes, not limited by handicap rules and derived from offshore solo racers.

Sure, it makes a lot of sense to use very beamy hulls for maximizing interior space, but when someone tells you that those hulls are also used to maximize sail performance, be suspicious: those hulls can make sailing easier, with less heel and less roll, but will not maximize performance, except on a very limited set of conditions and will lose a lot, sailing with low winds or upwind.

(drawing by Francois Chevalier)