Definition
An airplane upset that has progressed to the point where the aircraft's pitch attitude, bank angle, or airspeed has exceeded the parameters normally encountered in routine flight — typically pitch greater than 25° nose-up, pitch greater than 10° nose-down, bank angle greater than 45°, or airspeeds inappropriate for the conditions — and where active recovery action is required to return the airplane to normal flight.
Plain English
An upset that has gone past the early warning stage. The airplane is now well outside normal flying attitudes or speeds, and the pilot has to take deliberate recovery action to get it back under control.
Context Anchor
Used in upset prevention and recovery training when separating early recognition and prevention from actual recovery practice.
Derivation
"Fully-developed" simply means the upset has had time to grow into its full form. The wording matters because it signals a shift in pilot response: a developing upset can often be nudged back; a fully-developed one demands a structured recovery procedure.
Why Pilots Care
Distinguishes the point at which standard flight controls alone are insufficient and the structured recovery sequence must be used to avoid further loss of control.
Grounding Statement
Picture looking outside or at the flight instruments and seeing that the airplane’s nose, wings, or speed no longer match the flight path you meant to fly.
Intuition Check
“Upset” does not mean the pilot is emotionally upset. It means the airplane is in an unintended flight condition. “Fully-developed” does not mean hopeless; it means the upset is already present and needs recovery.
Example Sentence 1
Once the bank passed 60° with the nose well below the horizon, the instructor called it a fully-developed upset and prompted the student to begin the recovery sequence.
Example Sentence 2
In a fully-developed upset the pilot first unloads the wing to reduce angle of attack before attempting to roll the wings level.