Airfoil Data
HQ109

The HQ 1.0/9 AIRFOIL is a thin 5.5% chord-thickness airfoil with a maximum camber of 2.7% at 35% 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 -2.7°.

Thin airfoil theory predicts a stall angle near 11.9° and a peak lift-to-drag ratio around 51 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 HQ109 typically compare it against profiles of similar thickness: SIKORSKY SC1095R8 AIRFOIL, NLR-7223-43 AIRFOIL, AG27 Bubble Dancer DLG by Mark Drela | The AG2x airfoils are intended to be used on composite versions of the Bubble Dancer and the Allegro-Lite., GIII BL288 AIRFOIL, EH 2.0/7.0. The DAE 41 is another reference profile frequently considered alongside it.