Trajectory Accuracy Sensitivity to Modeling Factors

Abstract

This paper presents the analysis of sensitivity of aircraft trajectory prediction to relevant modeling factors such as wind, temperature, thrust settings, speed and aircraft mass. The topic is important because current and planned automation systems used for air traffic management, airline operations and Flight Management Systems rely on the accuracy of four dimensional trajectories (4DT) to plan and manage operations. Trajectory accuracy becomes even more critical in the Trajectory Based Operations (TBO) concepts envisioned for the Next Generation Air Transportation system (NextGen). Understanding the predictability envelope under various realistic conditions provides insight into the potential benefits and limitations of the efficiency gains that are expected from TBO. The aim of this study is to perform a systematic analysis of the accuracy of trajectory predictions across a wide range of aircraft types and operating environments. This is done by Monte Carlo simulations of the trajectory generation process that take into account the error distributions of the input variables to the trajectory generation algorithms. The prior distributions are calibrated using empirical data. The Monte Carlo method is used to generate the posterior distributions of trajectory accuracy performance metrics.