So can it “tack” through a headwind?
It doesn't have to.
It uses prevailing winds for the long haul and then motors to make land fall.
Or it simply winches down in adverse winds and starts engines.
But you may guess what the weakness is.
Ask any sailor.
It has to do with electricity.
Another wangdoodle design idea.
I suppose the price of fuel is driving the idea.
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