Airfoil Data
USA45

The USA 45 AIRFOIL is a 11.4% chord-thickness airfoil with a maximum camber of 5.7% at 30% 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 -5.7°.

Thin airfoil theory predicts a stall angle near 11.6° and a peak lift-to-drag ratio around 67 at typical UAV and light-aircraft Reynolds numbers — useful benchmarks before running a full XFOIL or NeuralFoil polar. The 11% thickness provides structural depth for main-spar placement without excessive drag penalty at moderate speeds.

The USA45 appears in the wing design of at least 6 documented aircraft, including designs from Fairchild and Keystone. Its proven track record across conventional and rotorcraft designs makes it one of the more field-validated profiles in the UIUC database.

Designers evaluating the USA45 typically compare it against profiles of similar thickness: FX 78-K-140/20, FX 78-K-140 A/20, NASA NLF(1)-0215F, EPPLER 49 AIRFOIL, AH 79-100 C AIRFOIL. The GOE 223 (MVA H.34) AIRFOIL is another reference profile frequently considered alongside it.