VANCOUVER ISLAND WINDTALK

Even the Foiling Big Boys Bronco!!! 2021 - 8 ton - 75’ - America’s Cup boats.

sheet in hard and I bet they can throw a loop.

It will be interesting to see how fast the new foiled hulls go in the upcoming Vendee Globe. Go Alex Thomson! (Hugo Boss).

TonyT1000 wrote:It will be interesting to see how fast the new foiled hulls go in the upcoming Vendee Globe. Go Alex Thomson! (Hugo Boss).

Very fast until they hit a semi submerged container or similar. Few ocean foilers seem to be able to go long distances without breaking.

My bet is that the first 2-3 finishers take another 2-3 days off the Vendee time record.

Ya I agree. Point a few degrees higher maybe, foil in times when not quite enough breeze to plane, that’d easily be days. Looks like fun.
It’s all about the helmsman I guess. Can’t sheet fast enough on those big boats. Tricky business. Good thing someone else paid for the boat.

Vendee boats have been foiling for a while no? But only partially airborne.
I think the Volvo Ocean Race is going to a similar partial foiler now too.

Vendee Globe Race - 18800 nautical miles in 74 days = 10.6 knots avg. speed.

Muey respect for these sailers, but there is still a ways to go for the Vendee Globe boats. Larson (no not the farside guy) predicted, post Sailrocket record, that a foiling sailboat would travel 1200 nautical miles in 24 hours in the open ocean (kite powered). A project he has been working on is a 600 mile per day open ocean alternating days sailing/battery powered transport ship. This would be double the Vendee Globe boats average speeds (10.6 knots vs 22 knots).

The real difficulty and reward is transiting from sub cavitation to super cavitation. I spoke with Tom Speer (Speer is the grandfather of a lot of our present kite/windsurf/sup etc. foil designs, along with NACA) and Stefano Brizzolara (US Navy foiling architect) about a year and half ago. The discussions were about traversing the sub/super cavitating hydrofoil boundary layer (53 knots to 65 knots, give or take). Speer did not have a way to model this. It looks like Brizzolara might have a design.

Once we get past (way out past) the apparent wind (kite) and apparent lift (hydrofoil) super-cavitating, hydrofoil boundary layer turbulence the theoretical speeds are mind boggling.

Larson’s Sailrocket struck me as being on the lower limit of supercavitating hydrofoil speed and hence all the vehicle quake in the videos. He sounds like the guys that first broke the speed of sound; like they are about to get shaken apart. Once out past the boundary layer everything smoothes out, until you hit something (ouch).

I am looking forward to the first kiter/sailer who consistently achieves supercavitating foil speeds. Having experienced a few times the spine-tingling massive acceleration from both the race kite building apparent wind and race foil building apparent lift simultaneously I can only imagine what that might feel like. “Danger Will Robinson. Danger”!!!
https://www.youtube.com/watch?v=OWwOJlOI1nU