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
City of Sails Chorus Chorus, ANZAC Day 1979. Of the 40 or so men there, about 35 turned up on the initial rehearsal night. Wayne Senior, TVNZ Music Personality, vocal and band arranger was appointed as the initial Musical Director. City of Sails Chorus The Auckland City of Sails Chorus is one of New Zealand's top male choruses singing mainly barbershop music. It is based in Auckland and has been active since the inception of NZABS (New Zealand Association Of Barbershop Singers, renamed in 2015 as BHNZ - Barbershop Harmony NZ) in 1979. BHNZ is an affiliate of the governing Barbershop Harmony Society. The