Which condition primarily leads to a stall in aviation?

A stall in aviation primarily occurs due to a disruption of airflow over the wings. This disruption can happen when the angle of attack—the angle between the wing's chord line and the oncoming airflow—exceeds a critical limit. When this critical angle is surpassed, the smooth airflow over the wing is disturbed, causing a significant loss of lift. The wing is no longer able to generate sufficient lift to support the weight of the aircraft, resulting in a stall.

Understanding this principle is crucial for pilots, as recognizing the signs of a stall and the conditions that lead to it is essential for maintaining control of the aircraft. Factors like high angles of attack during maneuvers, abrupt control inputs, or slow airspeeds are key contributors to such airflow disruptions.

While high speed during descent, excessive weight, and low fuel levels can affect flight performance and safety, they do not directly cause a stall in the same manner as the airflow disruption over the wings. Therefore, the correct answer emphasizes the critical relationship between the angle of attack and lift generation.