== Upwind vs Downwind HAWT == 
 A subtle advantage of upwind HAWT is that the lopsided weight of the rotor is upwind, so wind pressure on the tower is offset to some extent by the weight of the rotor. For a downwind HAWT the lopsided weight of the rotor adds to the wind pressure on the tower. There is a similar feature in large modern sailing ships; the masts lean sternwards, & this lopsided weight offsets to some extent the pressure of the wind on the mast.