Airfoil Data
E856

The EPPLER 856 AIRFOIL is a 13.0% chord-thickness airfoil with a maximum camber of 6.5% at 36% chord, suited to high-lift UAV wings, RC sailplanes, and low-Reynolds-number slow-flyers. At zero angle of attack the cambered geometry generates positive lift, giving an estimated zero-lift angle of -6.5°.

Thin airfoil theory predicts a stall angle near 11.2° and a peak lift-to-drag ratio around 70 at typical UAV and light-aircraft Reynolds numbers — useful benchmarks before running a full XFOIL or NeuralFoil polar. The 13% thickness provides structural depth for main-spar placement without excessive drag penalty at moderate speeds.

Designers evaluating the E856 typically compare it against profiles of similar thickness: GOE 646 AIRFOIL, GOE 692 AIRFOIL, GOE 225 (MVA H.35) AIRFOIL, WORTMANN FX 66-17AII-182 AIRFOIL (AS TESTED AT NASA), GOE 675 AIRFOIL. The GM15 (smoothed) is another reference profile frequently considered alongside it.