Airfoil Data
S4096

The S4096 (designed for the E-flite UMX ASK-21 scale RC sailplane) is a 8.4% chord-thickness airfoil with a maximum camber of 4.2% at 34% 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 S4096 typically compare it against profiles of similar thickness: EPPLER 326 AIRFOIL, GOE 123 AIRFOIL, GOE 401 AIRFOIL, GOE 279 (DAIMLER X) AIRFOIL, FX 74-080. The TsAGI 8% AIRFOIL is another reference profile frequently considered alongside it.