A symmetric airfoil’s lift coefficient (Cl) versus angle of attack (alpha) graph displays a linear increase in Cl at low alpha, followed by a sharp drop after the stall angle. This reflects the airfoil’s ability to generate lift due to the pressure difference created by the curved upper surface, which reaches a maximum at the stall angle before airflow separation occurs. Understanding this graph is crucial for aircraft design, as it determines the aircraft’s lift and drag characteristics, which are essential for optimal performance.