winglet-designlisted

Use when you must size a winglet as a wingtip device for induced-drag reduction on a fixed-wing aircraft: compute the effective span extension and the effective aspect ratio from the winglet height fraction and the cant angle, estimate the improved span efficiency, the induced-drag factor and the induced-drag coefficient at a reference lift coefficient, the percent drag reduction, and the root bending moment penalty at the wing root, then size the winglet height by bisection to hit a target drag reduction. Produces the winglet height, the effective aspect ratio, the drag reduction and the bending penalty that gate the wingtip device trade. Trigger: winglet design, wingtip device, induced drag reduction, effective aspect ratio, span efficiency, cant angle, winglet height, root bending moment penalty.
ashfordeOU/aero-agent-skills · ★ 0 · AI & Automation · score 78

Install: claude install-skill ashfordeOU/aero-agent-skills

# Winglet Design (aerodynamics/wing-design/winglet-design) Use when the task is the wingtip device trade for induced-drag reduction: sizing the winglet height and cant from the reference wing geometry and a target drag reduction, and weighing the drag gain against the root bending moment penalty. This leaf implements the effective-span extension model in pure Python, stdlib only. It pairs with aerodynamics/wing-design/wing-planform-design for the reference planform, and with vehicle-design/sizing/wing-planform-sizing and the drag-polar leaves for the system context. The improved span efficiency and bending penalty models are documented conceptual approximations for a preliminary trade; a real winglet design needs a VLM/CFD pass and a structural FEM pass. ## Domain quick reference - Effective span extension: extension = K_HEIGHT * height_frac, with K_HEIGHT = 0.8 the documented fraction of the winglet height that acts as span extension. height_frac is the winglet height over the local semi-span. - Cant weighting: cant_factor = cos(cant_deg). A vertical winglet (cant 0) keeps the full effect; a flat tip (cant 90) loses it. - Extended span and effective aspect ratio: b_eff = b * (1 + 2 * cant_factor * K_HEIGHT * height_frac) adds both tips, and AR_eff = b_eff^2 / area. - Improved span efficiency: e_eff = 1 - (1 - e_base) / (AR_eff / AR) with AR = span^2 / area. Documented approximation: the drag factor k = 1 / (pi * e * AR) shrinks with the effective-AR gain.