1 2 Clancy, L.J., Aerodynamics, section 5.14 ↑ Clancy, L.J., Aerodynamics, sections 5.17 and 8.9 ↑ McLean, Doug (2005). Wingtip Devices: What They Do and How They Do It (PDF). 2005 Boeing Performance and Flight Operations Engineering Conference. p. 4.5.