Airfoil Data
NACA2421

NACA 2421

Max Thickness
12.38%
Max Camber
6.19%
0.15 0.05 -0.05 -0.15
0.0 0.2 0.4 0.6 0.8 1.0
Chord (x/c)
Click to expand

Airfoil Geometry

NACA2421

NACA 2421

Max Thickness
12.38%
Max Camber
6.19%
0.15 0.05 -0.05 -0.15
0.0 0.2 0.4 0.6 0.8 1.0
Chord (x/c)
Profile
Camber line
Chord line

Press Esc or click outside to close

Wing Geometry Simulator

Live Geometry
Aspect Ratio 3.33
Area (S) 0.300
MAC 0.311m
Taper (λ) 0.50
Params

The NACA 2421 is a 12.4% chord-thickness airfoil with a maximum camber of 6.2% 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 -6.2°.

Thin airfoil theory predicts a stall angle near 11.5° and a peak lift-to-drag ratio around 69 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 NACA2421 appears in the wing design of at least 2 documented aircraft, including designs from CLW and Curtiss-Wright. Its proven track record across canard designs makes it one of the more field-validated profiles in the UIUC database.

Designers evaluating the NACA2421 typically compare it against profiles of similar thickness: GOE 413 AIRFOIL, RONCZ 1082 VOYAGER ROOT OUTER AFT WING AIRFOIL, GOE 425 AIRFOIL, CLARK YM-18 AIRFOIL, HQ 3.5/18 AIRFOIL. The NACA 2.5411 is another reference profile frequently considered alongside it.

Aircraft Using the NACA2421 Airfoil

Aircraft
2
Manufacturers
2
Tapered wings
2
Top manufacturer
CLW
2 aircraft
CLW Curlew
CLW
NACA 2421NACA 2418
Curtiss-Wright X-19
Curtiss-Wright
NACA 2421NACA 64-618

Wing lofting: 2 of these aircraft taper from NACA2421 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 NACA2421 frequently compare it against profiles with comparable geometric constraints. Below are the closest matches based on maximum thickness (12.4%) and max camber (6.2%).

Similar by Camber
Loading calendar...