Airfoil Data
MH121

The MH 121 8.76% is a thin 6.8% chord-thickness airfoil with a maximum camber of 3.4% at 48% 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 -3.4°.

Thin airfoil theory predicts a stall angle near 11.9° and a peak lift-to-drag ratio around 55 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 MH121 typically compare it against profiles of similar thickness: HQ 2.5/9 B AIRFOIL, HQ 2.5/9.0 smoothed by Eppler, GOE 6K AIRFOIL, GOE 566 AIRFOIL, KC-135 BL200.76 AIRFOIL. The MH 106 13.07% is another reference profile frequently considered alongside it.