How do you optimize winglet design for maximum efficiency?

Winglet optimization involves multi-disciplinary trade-offs: Aerodynamic parameters include cant angle (typically 15-75 degrees), toe angle, twist distribution, sweep, and height; Analysis uses vortex lattice or panel methods for induced drag, CFD for viscous effects and interference; Structural impact (increased root bending moment requiring wing strengthening); Weight penalty assessment; Manufacturing cost; Retrofit vs new design considerations. Modern blended winglets and raked tips are optimized using adjoint-based CFD methods. Target 3-6% fuel burn reduction must exceed weight and cost penalties. Optimization considers cruise point but also off-design conditions and buffet boundaries.