Airfoil Data
N9

The N-9 is a 8.5% chord-thickness airfoil with a maximum camber of 4.2% at 30% chord, suited to general-aviation and UAV wing design. At zero angle of attack the cambered geometry generates positive lift, giving an estimated zero-lift angle of -4.2°.

Thin airfoil theory predicts a stall angle near 11.8° and a peak lift-to-drag ratio around 59 at typical UAV and light-aircraft Reynolds numbers — useful benchmarks before running a full XFOIL or NeuralFoil polar. The slim profile minimises pressure drag at higher speeds but leaves limited spar depth for structural integration.

Designers evaluating the N9 typically compare it against profiles of similar thickness: NASA/LANGLEY LS(1)-0413 (GA(W)-2) AIRFOIL, GOE 379 AIRFOIL, A18 (original), GOE 328 AIRFOIL, MARSKE PIONEER IA AIRFOIL (NACA 23112/43012A HYBRID). The DORNIER A-5 AIRFOIL is another reference profile frequently considered alongside it.