What does the term "VS" signify in aircraft operation?

The term "VS" specifically refers to stall speed in a specified configuration, which is a critical performance parameter in aircraft operation. Stall speed is the minimum airspeed at which an aircraft can maintain level flight and is essential for safe operation, especially during takeoff and landing phases when the aircraft is at lower speeds. This parameter is influenced by aircraft weight, configuration (such as flaps extended or retracted), and the current flight condition.

In essence, knowing the stall speed helps pilots understand the limits of their aircraft during different phases of flight and enables them to avoid unintentional stalls. It is a vital factor for flight safety and proper aircraft handling, making it crucial for pilots to be aware of this speed and how it varies with specific configurations of the aircraft.