What does Vs represent?

Vs represents the stall speed without flaps. This speed is critical for pilots because it indicates the minimum speed at which the aircraft can maintain controlled flight in the clean configuration, meaning with no flaps deployed. Understanding this speed is vital for safe flight operations, particularly during approaches and landings, where pilots need to avoid entering a stall condition.

Best angle of climb speed (or Vy), stall speed with flaps, and flaps extend speed are all important parameters, but they pertain to different phases of flight or configurations of the aircraft. Stall speed with flaps reflects the aircraft's behavior when the flaps are deployed, which decreases stall speed and allows for slower flight without stalling. The flaps extend speed is a specific airspeed at which deploying flaps is recommended for safe operation. Each of these speeds has its own significance in flight training and operations, but Vs specifically refers to stall speed in the clean configuration, making it a crucial figure for pilots to understand and apply during flight.