I expect the wind to be either much to strong or to weak.
Sure. When is it otherwise?
Should it try to keep the schedule or aim for peak performance?
What kind of sails would give the best overall performance in an open
area?
Why not use the sails as a wind turbine to drive a staionary
generator, that way the vehicle can be lighter & more
streamlined, and powered by electricity which can be
efficiently transmitted over long distances. No z-shaped
rail routes.