Airfoil Data
E556

The EPPLER 556 AIRFOIL is a 10.2% chord-thickness airfoil with a maximum camber of 5.1% at 36% 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 -5.1°.

Thin airfoil theory predicts a stall angle near 11.7° and a peak lift-to-drag ratio around 64 at typical UAV and light-aircraft Reynolds numbers — useful benchmarks before running a full XFOIL or NeuralFoil polar. The 10% thickness provides structural depth for main-spar placement without excessive drag penalty at moderate speeds.

Designers evaluating the E556 typically compare it against profiles of similar thickness: AS6099 | Ananda-Selig | AIAA Paper 2018-0310, AH 93-K-131/15, EPPLER 715 AIRFOIL, FX 60-157 AIRFOIL, USA 48 AIRFOIL. The NACA M6 is another reference profile frequently considered alongside it.