What describes the entry phase of a spin?

The entry phase of a spin is characterized by the initiation of rotation and the occurrence of yaw. During this phase, one wing exceeds its critical angle of attack, leading to an asymmetrical stall that results in the aircraft yawing towards the stalled wing. This yawing motion is critical as it sets the dynamic conditions for a spin to develop.

In this context, rotation refers to the aircraft beginning to rotate around its vertical axis, which is a defining feature of a spin entry. The yaw component is particularly important because it indicates that the aircraft is moving into a fully stalled condition where one wing has lost lift while the other continues to produce it, leading to a noticeable yawing motion.

Understanding this phase is vital for pilots and students of aviation, as recognizing and responding appropriately to spin entry conditions can be crucial for maintaining control of the aircraft.