Size doesn't matter so much with foils once you're above a certain point.

Cavitation happens on the part of the foil that is most highly loaded and doesn't spread under steady-state conditions. You could ventilate the foil as a result of cavitation if the boats ride height changed dramatically.

I don't know if it is a design thing or it is just the way it happens, but many aircraft wings will stall at the wing root first hence the areolons being outboard to still have authority to control the aircraft.

sorry,.. was just re-stating what was already said above...

As Sam mentioned, the cavitation will start small on a small section of the foil where it is creating the most lift (vacuum). If speed continues to grow, the cavitation will spread. In this case, the cavitation will limit the lift of the foil and start to slow the boat down as it tries to maintain foiling (or the hull touches the water). It probably wouldn't be very dramatic.

I was going to ask why the cavitation started where it did near the outer edge of the foil rather than the base where it attaches to the vertical surface.

would the rake angle of the leading edge have anything to do with that?

Would an inverse rake angle help or hurt? Let's assume nothing in the water would get hung up on it

I envision the boats flipping end over end, breaking into 100 pieces and at least one fireball. Much more exciting that way.

A forward rake angle helps you with ventilation but not cavitation.

Random thought but has anyone compared the relative conditioning of the two teams? We all know we have sex-breath McGee on ETNZ who clearly sounds like he's on mile 25 of a marathon by the last leg - but I have to say that the Oracle guys don't look nearly as spent when the race is over - at least in the later stages of the event.

You think that it might play a part in the seemingly sluggish maneuvering by ETNZ?

(The race has inspired me to go back to the gym FWIW)

Race 17
1.6 knot flood current, 24.6 knot wind limit
race 18
1.1 knot flood, 24.1 knot wind limit

Big winds forecast today

Guess who's back?

He doesn't want to take any more chances that he won't be able to fulfil his dream/promise to return to monohulls? I'd be more impressed if he took the wheel.

Mike

Hey while we're waiting... let's start a top 10 list of things from this regatta that you can apply to every day life (since $100,000,000/boat technology will not readily trickle down to our level of the sport).

Here's one (inspired by the gym comment above):

If you're sitting in your office chair, and you lean to one side, and the sounds that come from the chair remind you of the groaning rigs of the AC72s, you might want to find your way back to the gym...

Mike

I'm seeing a forecast of 16 kts out of the east at 2pm local.

You don't need the gym. A little silicone spray will fix that.

Out of the East? Are you ok Jake?

Wind 260 at 20.7 kts, 22.5 kts peak

That's awfully close to the limit...

Mike

Philip where are you pulling weather data from?

finally! Thanks for that investigative journalism

It's the live chatter feed
http://live.virtualeye.tv/Chatter/chatter_100.html

TIM = Telemetry Interface Metadata

It's the source from the race committee. Wind comes from the Automated Wind monitor and reporter.