Anticipating Critical Instability in Ground Handling Operations During Aircraft Turnaround Through Constructal Flow Dynamics

Background: Aircraft turnaround is a finite operational system in which aircraft, passengers, baggage, information, personnel, Ground Service Equipment, and temporal capacity interact under strict safety and time constraints. This study examines how local Operational Disturbances propagate through this architecture and develop into Systemic Instability before an Observable Delay occurs. Methods: The methodology combines structural observation of approximately 150 real turnarounds, Conceptual and Mathematical Modeling, an Operational Dependency Network, and discrete-event simulation. Constructal Flow Dynamics are used to represent disturbance access, propagation resistance, buffer consumption, absorption, and residual capacity. Results: The analysis shows that unlimited exponential propagation is incompatible with a finite turnaround system. Exponential growth provides only a local approximation, whereas logistic dynamics represent the transition from the Invasion Phase to the Consolidation Phase and eventual saturation. The model-generated scenarios reproduce complete absorption below the propagation threshold and increasing residual disturbance after available buffers are exceeded. The framework also identifies an Invisible Time Window in which a Pre-Critical State may be detected. Conclusions: Observable Delay may represent the externally visible manifestation of earlier internal degradation. The proposed framework supports anticipatory operational stabilization, subject to Safety, Security, and human oversight. Statistical calibration and out-of-sample predictive validation remain necessary.