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It's been long since the sailors out there know that fact. Ships create their own wind when close hauled. Check out http://en.wikipedia.org/wiki/Hydropt%C3%A8re
by snippyhollow 16y ago
It's been long since the sailors out there know that fact. Ships create their own wind when close hauled. Check out http://en.wikipedia.org/wiki/Hydropt%C3%A8re http://en.wikipedia.org/wiki/Hydropt%C3%A8re for a particularly striking evidence!
- fab13n 16y agoThe point that made it counter-intuitive, here, is the "under the wind" part. The (false) idea is, if a 20km/h wind pushes your back, once you're close to 20km/h, you've got almost zero relative wind, so you shouldn't be able to accelerate further. Boats, including the hydroptere (which is special because of vertical lifting, but behaves as a normal sailboat in the horizontal plane), can go faster than the wind when then wind comes from the front, not when it comes from the back. The essential difference is, boats use water resistance sideways, i.e. they tend to behave as if they were on railtracks. The demonstrator in the article exploits rolling resistance, which boats try to minimize.
- snippyhollow 16y agoYes, they create their own wind downwind with a propeller (+ wheels and ground resistance) where a sailboat creates her own wind with her speed and water resistance / aerodynamics (instead of mechanics) but it's the same principle underneath: use your own speed to create your own wind (that will push you).
- Yaggo 16y ago> [Boats] can go faster than the wind when then wind comes from the front, not when it comes from the back. True, but it may be worth of mentioning that no regular sailboat (i.e. without underwater propulsion) can go directly to upwind (0 degrees). For modern sailboats, the maximum upwind direction is roughly 45 degrees, the sidewind (90 degrees) being the most optimal.