Saturday, April 08, 2006

VO80 looses half a point

Movistar hung on to their lead just long enough to deny ABN1 the prize of being first to round the Fernando de Noranha scoring gate. I think Mike Sandersons great pile of points can cope with being half a point smaller than it might have been if only - for example - his jib hadn't come tumbling down just after the Rio start.

Over the last two days there has been a near drag race for the gate where boat speeds can be compared, and its no surprise to see that the greatest ground was covered by ABN1.

Interestingly the next best averages were from Ericsson, who are gradually catching up with Pirates, so maybe their luck has changed - unlike the boat's skipper's name in Virtual Spectator which seems a bit behind the times (see graphic above).

But what is the source of Black Betty's power, what Bouwe Bekking has called the first VO80? Over the last 3 days it has averaged about 0.7 knots faster than the rest of the fleet. That's a significant difference and is the subject of much speculation.

On Sailing Anarchy there's been an interesting theory on the forums about how the keel's weight is not symmetric around the attachment and there is sufficient flex in the keel blade to permit it to twist and cause a downwards lift that increases the righting moment. Its a good idea, but apart from being illegal, there would also be problems with drag and the flex could permit oscillations.

Other clues have come from the emails. For example there was an intriguing comment from Mike here when sailing parallel to Pirates in the southern ocean "they changed to their sail as close to ours as they had and for sure they were closer in speed. We might have given away a little bit of a secret to our mates, the Pirates, but I am sure they will keep it too themselves."

That would suggest sail differences. Paul Cayard also made some comments here where he says of ABN1: "
They had the time to build their second boat with the knowledge from the first, optimising the strength and the weight and making the bulb as heavy as possible. This, coupled with greater overall beam, makes for a much more powerful boat with the possibility of a wider sheeting angle, something very useful at the moment with a lot of reaching on the menu."

So there are other options than twisting keels to explain ABN1s speed. But it must be frustrating when one boat is clearly significantly faster making the Volvo Ocean race winner so little in doubt.

While the key battles to watch are for second and third, never forget the goldern rule "to finish first you first must finish". It ain't over yet.

Graphics from Virtual Spectator

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