Foil minimal speed

[fredi]

Hello
On GPS tracks I can see that I start to fly with my 90cm/2000cm2/tick foil (Gong XL classic) at 6 knots.
Total weight of me+board+foil+weitsuit+wing or paddle is around 85kg (190lbs). It probably vary on sqrt of the weight (if I take the hypothesis that lift if proportional to speed^2), so speed should be similar for lighters or heavier riders.
So I think it's an interesting metric. I have GPS tracks of downwinds, speed measurement of sailing with experimental sails, I've also measured river stream speeds. So I can know if it will work or not with my foil.

Does someone have done measurement of minimum flying speed for other foils that mine? Does the 100cm wide foils can fly at 4 knots?

[lakemichiganwingfoiler]

What size board are you using to get going in 6 knots?

[Dontsink]

Stall speed is not a fixed value for a given foil if you change the weight it has to hold up.
Stall occurs always at the same Angle of Attack for a given foil,this is constant (same water,no bank ,no yaw etc...).
So a heavier rider will stall at higher speed than a lighter one on the same foil.He needs more Lift so at same speed he needs more AOA.

[surfcowboy]

Lake Michigan, I think they are talking about speed over water, not wind speed. I have that same foil and probably about the same weight and that tracks with what I’ve seen.