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The concept is not very different from the way a sloop works... the lift is UP and FORWARD and normal to the wind direction.... ie directly INTO the wind.

To sail off the eye of the wind.... the sail/foil needs to rotate and then a keel is needed to prevent leeway.

Don't have time today to make some concept sketches... use your imagination.
 

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The concept is not very different from the way a sloop works... the lift is UP and FORWARD and normal to the wind direction.... ie directly INTO the wind.

To sail off the eye of the wind.... the sail/foil needs to rotate and then a keel is needed to prevent leeway..
I think you have this backwards. The keel's offsetting surface area becomes more relevant, the closer to the wind you get, not as you fall off. Sketch the vectors.

Lift from a sloop that is head into the wind, would be predominantly be to the side, not forward.
 

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excuse me? Whether or not this concept can sail directly into wind or not... the fact remains that the sum of the vectors is forward no matter how small it is.
Not sure what the excuse me means? If you prefer an argument, I'll pass.

If I misunderstand, I'll add that there may be a small theoretical forward vector, only if you ignore the drag vector.
 

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Your analogy to an airplane doesn't work. On an airplane, the wing provides lift, not forward momentum. The propeller and engine provide forward momentum.
 

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Minni I think you are not understanding this though experiment. I encourage discussion not an argument.

A vertical mast w/ sail when sailing close to the wind... generates a small vector more or less forward. The keel resists heel and making way to leeward. The sum of the vectors allows the boat to move almost perpendicular the the front edge of the sail. This is possible because lift is created by the sail form and the lift is normal to the surface of the sail with all the sideways forces countered by the hull and keel. If the rig was mounted on a flat raft it would sail sidways I believe... if it didn't tip over.

If the mast and sail and boom are rotated to horizontal... looking at the force vectors... they would be mostly up and some forward. This is how a plane's wing lifts the plane. But to fly and get lift you need adequate wind speed. The lift is enough to overcome gravity. Planes move forward using props or jet thrust... and that creates apparent wind!

A glider we know will not take off sitting on the runway facing the wind. It needs to be towed to get apparent wind and lift... and it has some momentum and being light they are able to fly... as long as their is enough apparent wind.

The horizontal mast is no different. It needs a fair amount of apparent wind to over come momentum. However if there is enough apparent wind AND the sail is properly trimmed there would be a forward component and no lee component.

Yes or no?
 

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Your analogy to an airplane doesn't work. On an airplane, the wing provides lift, not forward momentum. The propeller and engine provide forward momentum.
correct...but on a glider there is no prop or engine... yet the plane moves forward... it needs to be towed to get up apparent wind speed so it can lift off and it also give it initial forward motion. But if there were no forward motion there would be no apparent wind and it would drop from the sky.
 

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I dont think i would want a keel on SanderOs theoretical boat. I think light and fast would be the way to go,maybe a tri, maybe foiling. Higher apparent wind speed, less hull in the water, less drag, no big hunk of lead to cart around. I still dont think you could sail straight upwind though. I dont think the technology currently exists to overcome all drag.
 

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I dont think i would want a keel on SanderOs theoretical boat. I think light and fast would be the way to go,maybe a tri, maybe foiling. Higher apparent wind speed, less hull in the water, less drag, no big hunk of lead to cart around. I still dont think you could sail straight upwind though. I dont think the technology currently exists to overcome all drag.
This may be true... water drag is much more than air drag... so yes very slick and small underbody would be in order. And you DO need a lot of apparent wind. But it is amazing how little wind can get a multi ton vessel moving.
 

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Minni I think you are not understanding this though experiment. I encourage discussion not an argument.

A vertical mast w/ sail when sailing close to the wind... generates a small vector more or less forward. ....
Draw the cord of the sail, when close to the wind, then draw the same cord on a horizontal wing. You'll see the difference.

The vertical sail/wing is at a very different angle of attack (especially when close, but not directly into the wind) from your theoretical horizontal wing in relation to the forward direction of the vessel.
 

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How about this... what would the impact be on how your sloop would sail of you could can't the mast (tip it at its base) to one side or the other. Would you kill your ability to point and make more leeway? I think so if it is tipped to leeward. If it is tipped to windward what would happen? stall?
 

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Draw the cord of the sail, when close to the wind, then draw the same cord on a horizontal wing. You'll see the difference.

The vertical sail/wing is at a very different angle of attack (especially when close, but not directly into the wind) from your theoretical horizontal wing in relation to the forward direction of the vessel.
correct.... but why can't the horizontal sail be rotated? It can... the chord can be any angle... not all will work of course... the luff has to be... should be higher than the leach. no?
 

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A glider would not work without gravity.
 

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correct.... but why can't the horizontal sail be rotated? It can... the chord can be any angle... not all will work of course... the luff has to be... should be higher than the leach. no?
You're starting to follow my point. On your horizontal wing sail, directly into the wind, the luff would be slightly higher than the leach, ie the cord indicating the leading edge is slightly higher than the trailing edge, relative to the forward vector of the boat. This is exactly the opposite of a vertical sail on a close haul. Sketch them out. The perpendicular of the cord is pointing aft, not forward like a sail.
 
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