Definition
The phase of flight in which an airplane transitions from stalled flight into an autorotative spin. It begins when one wing exceeds the critical angle of attack while yaw is present, causing that wing to drop and the airplane to start rotating about its vertical axis. Spin entry typically requires a stall combined with uncoordinated flight (rudder input, slip, or skid), and ends once the spin becomes fully developed.
Plain English
Spin entry is the moment a stalled airplane starts to rotate and fall into a spin. It happens when the airplane is already stalled and one wing drops while the nose yaws, beginning the spinning motion.
Context Anchor
You will see this term in spin awareness training, stall practice, instructor demonstrations, and accident discussions about loss of control.
Derivation
From 'spin' (rotational motion) and 'entry' (the act of going into something). The phrase simply names the beginning portion of a spin -- the doorway between a stall and a fully developed spin.
Why Pilots Care
Recognizing the spin entry allows immediate application of recovery inputs before the spin becomes fully developed and altitude loss becomes critical.
Grounding Statement
Picture an airplane held too slow with the nose high; if one wing drops and the nose starts turning as the airplane stalls, that is the start of spin entry.
Intuition Check
Spin entry is not just starting a turn. A spin entry requires both a stall and yaw; without the stall, the airplane may be turning, but it has not entered a spin.
Example Sentence 1
The instructor demonstrated how a skidding turn at low airspeed could lead to a spin entry if the airplane was allowed to stall.
Example Sentence 2
Early recognition of the spin entry is essential so the pilot can apply opposite rudder and forward stick without delay.