Airfoil Data
NACA634221
NACA 63(4)-221
Wing Geometry Simulator
The NACA 63(4)-221 is a 11.5% chord-thickness airfoil with a maximum camber of 5.8% at 35% 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 -5.8°.
Thin airfoil theory predicts a stall angle near 11.6° and a peak lift-to-drag ratio around 68 at typical UAV and light-aircraft Reynolds numbers — useful benchmarks before running a full XFOIL or NeuralFoil polar. The 12% thickness provides structural depth for main-spar placement without excessive drag penalty at moderate speeds.
The NACA634221 appears in the wing design of at least 3 documented aircraft — notably by Convair. Its proven track record across canard designs makes it one of the more field-validated profiles in the UIUC database.
Designers evaluating the NACA634221 typically compare it against profiles of similar thickness: EPPLER 396 AIRFOIL, USA 29 AIRFOIL, GOE 530 AIRFOIL, GOE 769 AIRFOIL, EPPLER 554 AIRFOIL. The NACA 65-209 is another reference profile frequently considered alongside it.
Aircraft Using the NACA634221 Airfoil
Convair 11 YB-60 | Convair | NACA 63(420)-422 Mod | NACA 63(420)-517 |
Convair 36 B-36 Peacemaker | Convair | NACA 63(420)-422 | NACA 63(420)-517 |
Convair 37 XC-99 | Convair | NACA 63(420)-422 | NACA 63(420)-517 |
Wing lofting: 3 of these aircraft taper from NACA634221 at the root to a different tip section. Use the Tapered filter to isolate them, then click any tip airfoil link to compare geometries.
Related Airfoils
Engineers evaluating the NACA634221 frequently compare it against profiles with comparable geometric constraints. Below are the closest matches based on maximum thickness (11.5%) and max camber (5.8%).