Todd
I am referring to the lift generated by the side of the hull to resist leeway. The slightly flared leeward side of the lw hull will present an almost flat planing surface to generate sideways lift. Hulls with round bottoms and vee bottoms tend to skid sideways easier. For a given lateral area they have lower lift.
In terms of observations with this I have experienced the way hard chine hulls will bite in when pressed sideways. I rolled an outboard powered flat bottom dinghy when the chine dug in in a tight turn. A V bottom tuns much tighter because it lifts when forced sideways.
The flat panel on its side works the same way as the flat bottom on a hull in generating lift; both are planing surfaces. With regard to vertical lift, a flat bottom planes more readily than a V bottom. Meaning the flat bottom is better at generating lift for a given area.
With a sailing boat doing 15kts through the water with leeway of 6 degrees the sideways speed is 1.5kts. What shape hull section will produce more force resisting this sideways motion at 1.5kts; rectangular section, V section or round section? The shape that is hardest to move sideways will have less leeway than the others.
Rick
On 15/05/2011, at 4:42 AM, tsstproa wrote:
What type of lift are you referring to? BJust the simple fact of bottom panel being flat, Or generated lift due to shape of heeledor not so heeled flat bottom panels under water plane? surface area, shape, contour, etc...
Todd
--- In harryproa@yahoogroups.com.au, Rick Willoughby <rickwill@...> wrote:
>
The situation would not be as clear if the hulls
> have round or "v" sections because these cannot generate as much lift
> for the area as a flat panel.
>
> Rick
>
>
Rick Willoughby
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0419 104 821
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