Airfoil Data
S2091

The S2091-101-83 is a 8.8% chord-thickness airfoil with a maximum camber of 4.4% at 35% 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 -4.4°.

Thin airfoil theory predicts a stall angle near 11.8° and a peak lift-to-drag ratio around 60 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 S2091 typically compare it against profiles of similar thickness: GOE 264 AIRFOIL, E392 (10.15%), EPPLER 417 AIRFOIL, WORTMANN FX M2 AIRFOIL, GOE 596 AIRFOIL. The S1210 12% is another reference profile frequently considered alongside it.