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
MESO-SAILS noted. MESO-SAILS was thus deployed with Build 14 update in the Spring of 2014 and is still in operations when needed. The operator can choose between 1, 2, or 3 supplemental low-level scans with MESO-SAILS active. A study published in 2016 looked at how the MESO-SAILS radar scanning regime performed with respect to tornado debris signature (TDS) detection during the 2016 tornado season in the Iowa Region, compared to the distribution before its implementation. When tornado watches were active, MESO-SAILS was active 100% reflecting the National Weather Service expectations for such situations. Overall, it was found that the use of