Airfoil Data
FX74CL5140

The FX74_CL5_140 is a thick 16.9% chord-thickness airfoil with a maximum camber of 8.4% at 34% 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 -8.4°.

Thin airfoil theory predicts a stall angle near 9.9° and a peak lift-to-drag ratio around 75 at typical UAV and light-aircraft Reynolds numbers — useful benchmarks before running a full XFOIL or NeuralFoil polar. The 17% thickness provides structural depth for main-spar placement without excessive drag penalty at moderate speeds.

Designers evaluating the FX74CL5140 typically compare it against profiles of similar thickness: WORTMANN FX 72-MS-150B AIRFOIL, FX 69-274, TH 25816 HALE AIRFOIL, GOE 241 (MVA PR.1) AIRFOIL, GOE 448 AIRFOIL. The FX 74-CL6-140 is another reference profile frequently considered alongside it.