Wayne.B wrote:
On Wed, 22 Jul 2015 10:04:23 -0500, Califbill billnews wrote:

I remember a similar proposal to put the sails like on the the last
America's cup boats on a freighter to get some extra push. More practical
idea. Computer controlled, no dangerous cables to the sail.


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Wing sails. One problem is that they can't be reefed down in high
winds. The America's Cup boats use a crane to remove them every
night, and they have three or four different wing sizes depending on
the wind strength they are expecting on any given day.

Folding masts. Or feather the sail. Interesting article. 30% saving.
http://www.cnet.com/news/cargo-ship-...-percent-fuel/