Forces on sails to stay within the limitations of a craft's stability and power requirements, which are functions of hull (for boats) or chassis (for land craft) design. Sails derive power from wind that varies in time and with height above the surface. In order to do so, they are designed to adjust to the wind force for various points of sail. Both their design and method for control include means to match their lift and drag capabilities to the available apparent wind, by changing surface area, angle of attack, and curvature. Wind speed increases with height above the surface; at the same
Twin Sails Bridge April 2012 after the road surface had been relaid, the first motor vehicle crossing at 9.38AM. Problems with the bridge operation continued in the summer of 2012 with delays caused through the barrier operation and lifting mechanism as well as continuing defects in the road surface. The bridge was closed again beginning 16 November 2018 due to a hydraulic issue with its lifting mechanism. Twin Sails Bridge The Twin Sails Bridge (also known as The Second Harbour Crossing) is a double leaved bascule bridge in Poole, Dorset, England. The bridge provides a second road link from Poole Town Centre to