Airfoil Data
GLENNMARTIN4

The Glenn Martin 4 is a thick 15.4% chord-thickness airfoil with a maximum camber of 7.7% at 30% 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 -7.7°.

Thin airfoil theory predicts a stall angle near 10.4° and a peak lift-to-drag ratio around 73 at typical UAV and light-aircraft Reynolds numbers — useful benchmarks before running a full XFOIL or NeuralFoil polar. The 15% thickness provides structural depth for main-spar placement without excessive drag penalty at moderate speeds.

Designers evaluating the GLENNMARTIN4 typically compare it against profiles of similar thickness: AH 93-W-300, LIEBECK L1003 AIRFOIL, GOE 222 (MVA H.33) AIRFOIL, WORTMANN FX 72-MS-150A AIRFOIL, GOE 462 AIRFOIL. The RAE 102 AIRFOIL is another reference profile frequently considered alongside it.