Multicant Winglets

Abstract

A multicant winglet has a first blade section having a leading and a trailing edge, a first lowermost edge and a first uppermost edge, and a first central plane defined by the edges, and a second blade section having a leading and a trailing edge, a second lowermost edge and a second uppermost edge, and a second central plane defined by the edges. The first central plane is canted from vertical by a first cant angle, and the second central plane is canted from vertical by a second cant angle, the first cant angle unequal to the second cant angle.

1 . A multicant winglet comprising:
 a first blade section having a leading and a trailing edge, a first lowermost edge and a first uppermost edge, and a first central plane defined by the edges; and   a second blade section having a leading and a trailing edge, a second lowermost edge and a second uppermost edge, and a second central plane defined by the edges;   wherein the first central plane is canted from vertical by a first cant angle, and the second central plane is canted from vertical by a second cant angle, the first cant angle unequal to the second cant angle.   
     
     
         2 . The multicant winglet of  claim 1  comprising more than two blade sections canted at different angles from vertical. 
     
     
         3 . The multicant winglet of  claim 1  wherein the first blade section is a base or lower section having a base dimension between the leading and the trailing edges at the lowermost edge, and the leading and trailing edges converge to a second dimension less than the base dimension at the first uppermost edge. 
     
     
         4 . The multicant winglet of  claim 3  wherein dimension between the leading and the trailing edges of the second blade section at its lowermost edge is equal to the second dimension at the uppermost edge of the first blade section, and the leading and trailing edges of the second blade section converge further to the uppermost edge of the second blade section. 
     
     
         5 . The multicant winglet of  claim 1  wherein the uppermost edge of the second blade section is a straight edge, and further comprising a tip section having a lowermost edge equal in dimension to the uppermost edge of the second blade section, and wherein the leading and trailing edges of the tip section converge and join in a curved uppermost edge. 
     
     
         6 . The multicant winglet of  claim 5  wherein the tip section has a cant angle from vertical different than those of the first and the second blade sections. 
     
     
         7 . The multicant winglet of  claim 6  wherein the cant angle from vertical is greatest for the first blade section, next greatest for the second blade section, and least for the tip section. 
     
     
         8 . The multicant winglet of  claim 7  wherein the cant angle for the tip section is zero. 
     
     
         9 . The multicant winglet of  claim 1  wherein the second central plane of the second blade section is rotated in a horizontal plane by a toe angle from the first central plane of the first blade section. 
     
     
         10 . The multicant winglet of  claim 5  wherein the tip section is rotated in a horizontal plane by a toe angle from the second central plane of the second blade section. 
     
     
         11 . The multicant winglet of  claim 1  wherein the leading edges of the first and the second blade sections are swept back at a backswept angle from the position at the first lowermost edge of the first blade section. 
     
     
         12 . The multicant winglet of  claim 11  wherein the backsweep angle is between 25 and forty degrees inclusive. 
     
     
         13 . A lifting assembly comprising:
 a primary lifting element having a leading and a trailing edge and a central plane defined by the edges;   a multicant winglet comprising a first blade section having a leading and a trailing edge, a first lowermost edge and a first uppermost edge, and a first central plane defined by the edges, and a second blade section having a leading and a trailing edge, a second lowermost edge and a second uppermost edge, and a second central plane defined by the edges, wherein the first central plane is canted from vertical by a first cant angle, and the second central plane is canted from vertical by a second cant angle, the first cant angle unequal to the second cant angle; and   a contoured transition section having a first interface with a shape for joining to a cross section of the primary lifting element and a second interface with a shape for joining to a cross section of the first blade section of the multicant winglet, the contour of the transition section shaped such that the sections are joined to present the multicant winglet blades at their first and second cant angles.   
     
     
         14 . The lifting assembly of  claim 13  wherein the multicant winglet comprises more than two blade sections canted at different angles from vertical. 
     
     
         15 . The lifting assembly of  claim 13  wherein the first blade section of the multicant winglet is a base or lower section having a base dimension between the leading and the trailing edges at the lowermost edge, and the leading and trailing edges converge to a second dimension less than the base dimension at the first uppermost edge. 
     
     
         16 . The lifting assembly of  claim 15  wherein dimension between the leading and the trailing edges of the second blade section of the multicant winglet at its lowermost edge is equal to the second dimension at the uppermost edge of the first blade section, and the leading and trailing edges of the second blade section converge further to the uppermost edge of the second blade section. 
     
     
         17 . The lifting assembly of  claim 13  wherein the uppermost edge of the second blade section is a straight edge, and further comprising a tip section having a lowermost edge equal in dimension to the uppermost edge of the second blade section, and wherein the leading and trailing edges of the tip section converge and join in a curved uppermost edge. 
     
     
         18 . The lifting assembly of  claim 17  wherein the tip section has a cant angle from vertical different than those of the first and the second blade sections. 
     
     
         19 . The lifting assembly of  claim 18  wherein the cant angle from vertical is greatest for the first blade section, next greatest for the second blade section, and least for the tip section. 
     
     
         20 . The lifting assembly of  claim 19  wherein the cant angle for the tip section is zero degrees from vertical. 
     
     
         21 . The lifting assembly of  claim 13  wherein the second central plane of the second blade section is rotated in a horizontal plane by a toe angle from the first central plane of the first blade section. 
     
     
         22 . The lifting assembly of  claim 17  wherein the tip section is rotated in a horizontal plane by a toe angle from the second central plane of the second blade section. 
     
     
         23 . The lifting assembly of  claim 13  wherein the leading edges of the first and the second blade sections are swept back at a backsweep angle from the position at the first lowermost edge of the first blade section. 
     
     
         24 . The lifting assembly of  claim 23  wherein the backsweep angle is between twenty-five and forty degrees inclusive. 
     
     
         25 . The lifting assembly of  claim 13  wherein the first interface of the transition section with the primary lifting element comprises a mechanism enabling the toe angle of the multicant winglet to be adjusted. 
     
     
         26 . The lifting assembly of  claim 13  wherein the transition section comprises a plurality of openings connected to one or both of a pump and a suction mechanism, whereby air or other gaseous medium may be drawn in or pumped out through the openings. 
     
     
         27 . The multicant winglet of  claim 1  further comprising one or more boundary layer trip strips applied to surfaces of one or more sections, tripping laminar flow to turbulent flow. 
     
     
         28 . The multicant winglet of  claim 1  further comprising a mechanism providing vibration to sections of the winglet, the vibration changing patterns of laminar and turbulent flow.