⟿ NACA 4-DIGIT // THIN AIRFOIL THEORY

Airfoil Lab

AIRFOIL DESIGN & AERODYNAMIC ANALYSIS
NACA
2412
4 DIGIT
5 DIGIT
INSTANTANEOUS AERODYNAMICS
LIFT COEFFICIENT Cl
α = 5°
ZERO-LIFT AOA
αL=0
L/D RATIO
estimated
MOMENT Cm c/4
quarter-chord
CENTER OF PRESSURE
xcp
AERODYNAMIC CENTER
xac
PERFORMANCE CURVES
ⓘ Cl–α, zero-lift angle, and Cmc/4 are calculated from thin-airfoil theory (potential flow, small angle approximation). Cl = 2π(α − αL=0), valid in the linear region. Stall (~12–16°) is empirically smoothed. Drag Cd is APPROXIMATELY modeled with a thickness-dependent parabolic polar (Cd = Cd₀ + k·Cl²) — actual values depend on Reynolds number, surface roughness, and viscous effects.