Airfoil Data
S4095
S4095 (designed for the E-flite UMX ASK-21 scale RC sailplane)
Wing Geometry Simulator
The S4095 (designed for the E-flite UMX ASK-21 scale RC sailplane) is a thin 7.3% chord-thickness airfoil with a maximum camber of 3.6% at 29% chord, suited to high-speed UAVs, sailplane tip sections, and propeller blade design. At zero angle of attack the cambered geometry generates positive lift, giving an estimated zero-lift angle of -3.6°.
Thin airfoil theory predicts a stall angle near 11.8° and a peak lift-to-drag ratio around 56 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 S4095 typically compare it against profiles of similar thickness: RAE(NPL) 5212 AIRFOIL, RG 15A-1.8/11.0 AIRFOIL, GOE 372 AIRFOIL, GOE 585 AIRFOIL, SD2083 (9.0%). The AS6096 | Ananda-Selig | AIAA Paper 2018-0310 is another reference profile frequently considered alongside it.
Related Airfoils
Engineers evaluating the S4095 frequently compare it against profiles with comparable geometric constraints. Below are the closest matches based on maximum thickness (7.3%) and max camber (3.6%).