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post #49 of Old 02-18-2019
SanderO
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Re: sailing past close hauled?

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?

pay attention... someone's life depends on it
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