How does the stall warning system in an airplane work?

The stall warning system in an airplane is designed to alert pilots when the aircraft is approaching a stall condition, primarily by monitoring the angle of attack (AOA). When the angle of attack increases and reaches a certain critical level, the stall warning system activates, providing an audio or visual indication to the pilot. The specific mechanism often involves a sensor that responds to airflow, and as AOA increases, the system may use a pressure differential to trigger the warning.

This is an essential safety feature, as it provides pilots with an early warning that the aircraft is nearing its critical angle of attack, thus enabling them to take corrective action to prevent an actual stall. The stall warning is not dependent on altitude or throttle settings directly, nor does it activate randomly; instead, it is a critical measure based on aerodynamic principles related to the aircraft's performance.