Indeed, iceboats can make good both upwind and downwind at speeds greater than the wind. The structure supports the turbine by 2 upwind and 2 downwind masts. Other terms with broadly the same meaning are widely used, particularly "upwind" and "downwind". Racing dinghies usually have a daggerboard or centreboard to better sail upwind. The lateen sail proved to have better upwind performance for smaller vessels. Thus when a ship is tacking, it is moving both upwind and across the wind. Both carts and boats were able to turn and sail upwind. Better locations for wind turbines are far away from large upwind obstacles. Its disadvantage is a limited ability to sail upwind. The wind window rotation degrades the performance when riding fast in a path upwind. They may wait for a favorable wind to avoid sailing upwind. The drawing below shows the vector operations and resulting calculations for sailing upwind. Most horizontal axis turbines have their rotors upwind of the supporting tower. Dome dunes are rare and occur at the far upwind margins of sand seas. Beating allows the vessel to advance indirectly upwind.