What Is the Clark-Y Airfoil Aerodynamic Lift Slope Calculator?
The Clark-Y airfoil has an experimental zero-lift angle of attack of -3.8 degrees due to its positive camber.
Finite wingtip vortex downwash reduces the effective 3D lift slope compared to theoretical infinite 2D airfoil sections.
How Does the Clark-Y Airfoil Aerodynamic Lift Slope Calculator Work?
Applies Helmbold formulation to adjust 2D section lift slope a0 for finite wing aspect ratio AR.
Converts effective angle of attack (alpha - alpha0) to radians.
Evaluates overall 3D wing lift coefficient CL.
Clark-Y Airfoil Aerodynamic Lift Slope Calculator Formula & Variables
The core mathematical equation utilized by this calculator is expressed as:
Helmbold finite aspect ratio 3D lift slope transformation with Clark-Y zero-lift offset.
How to Use the Clark-Y Airfoil Aerodynamic Lift Slope Calculator
- Enter geometric angle of attack in degrees.
- Enter wing aspect ratio (span^2 / wing area).
- Optionally adjust section 2D lift slope a0.
Step-by-Step Example Calculation
Light UAV Wing Cruise Aerodynamics
Input Values:
Understanding Your Result
At 0 degrees angle of attack, the Clark-Y still produces substantial positive lift (CL ~ 0.38).
Higher aspect ratios increase the lift slope, producing more lift per degree of pitch.
Factors That Affect the Result
- Aspect ratio: Low aspect ratio wings suffer severe downwash, flattening the lift curve.
- Stall angle: Clark-Y exhibits gentle trailing-edge stall onset around 14° to 16° angle of attack.
When Should You Use This Calculator?
- Sizing wings for general aviation airplanes, gliders, radio-controlled planes, and propeller blades.
- Estimating cruise pitch attitude and trim settings.
Assumptions & Limitations
- Valid in linear attached flow regime below the stall angle (alpha < 12°).
- Assumes subsonic incompressible flight (Mach < 0.3).
Frequently Asked Questions
Calculation Accuracy & Reference Note
Calibrated against historic NACA Technical Report 586 wind tunnel measurements.