Etiology of Delays in Ground Handling Operations: A Mixed-Methods Root Cause Analysis

Ground handling processes, which are critical determinants of operational costs and schedule deviations in air transportation, constitute one of the most complex bottlenecks of flight delays. This study aims to analyze the root causes of delays in ramp operations, encompassing not only physical resource deficiencies but also operational blind spots and human factor dynamics. While existing literature predominantly relies on macro-level secondary traffic data, this study addresses a critical gap by capturing primary empirical insights from both frontline tactical and senior managerial levels, thereby offering a novel, non-linear framework for ground handling delay etiology. The research is structured with a Convergent Parallel Mixed Methods design, in which qualitative and quantitative data are simultaneously collected and synthesized. The dataset of the study is based on in-depth interviews conducted with 22 experienced field managers active in the Turkish aviation ecosystem and survey data collected from 264 ground handling personnel managing the operational critical path. The analysis results reveal that delays stem from non-linear "error chains" that trigger one another, rather than individual personnel errors. Comparative analysis of qualitative and quantitative data unveils a striking operational paradox: while management attributes delay to tangible resource deficiencies, field personnel report that the primary determinants are "Time Pressure" (4.12/5.0) and "Lack of Communication" (4.06/5.0) engendered by these deficiencies. While statistical data prove that workload intensity (3.88/5.0) pushes personnel toward procedural deviations (shortcutting), "personnel shortage" is observed as the most dominant common root cause in both qualitative (13.72%) and quantitative (13.95%) data. Furthermore, the fact that passenger-sourced problems (baggage/late acceptance) hover around the 14% band in both datasets substantiates the external dimension of the issue. The study demonstrates that the psychological pressure exerted on employees by physical infrastructure inadequacies increases operational deviations. In this context, it is concluded that preventing delays requires moving beyond traditional resource augmentation; instead, a proactive digital transformation strategy including Virtual Reality (VR)-based crisis simulations, A-CDM (Airport Collaborative Decision Making) integration, and IoT-based predictive maintenance models should be adopted.