The slowest speed an airplane can fly in straight, level, and unaccelerated flight is called the stall speed (Vstall). When an aircraft reaches its stall speed, the airflow over the wings becomes too disrupted to generate enough lift, causing the aircraft to lose its ability to maintain altitude and control. This phenomenon is known as a stall, and it can lead to a loss of lift, a sudden drop in altitude, and potentially a loss of control if not handled properly. The formula to calculate stall speed as follows:
Where:
- is the stall speed (in meters per second or feet per second),
- is the weight of the aircraft (in newtons or pounds),
- is the air density (in kilograms per cubic meter or slugs per cubic foot),
- is the wing area (in square meters or square feet),
- is the maximum coefficient of lift at stall.