Impact of Rapid Fuel Jettison Procedures on Air Traffic Management. Development and Implementation of an Advanced Fuel Jettison Simulation and Comparison with the ICAO Standard Procedure

Abstract

This thesis addresses the simulation of a fuel plume that arises from an aircraft’s fuel jettison procedure. The work focuses on the behavior of the plume in the airspace controlled by air traffic control (free atmosphere conditions). Therefore, the topic was investigated from an air traffic control perspective, including literature analysis on the fuel jettison emergency procedure and its general characteristics. Moreover, related work regarding the simulation of the fuel jettison plume was analyzed and thereupon models for multi-component evaporation, mass transport and dispersion and the corresponding boundary conditions were defined. Using the numerical models, a simulation of the fuel plume behavior was implemented and a visualization was integrated into an existing radar display. The visualization is capable of displaying the simulated plume location, its dimension, occurring fuel concentrations and remaining mass fractions. Furthermore, restriction areas that are prescribed by international regulations for the event of fuel jettison can be displayed. For a comparison of simulated plume area the regulatory restriction area, simulations of 27 test-cases with varying ambient temperature, wind speeds and directions were performed and the results were analyzed using the radar display visualization. The results indicate that fuel concentration limits from available studies regarding flammability and toxicity are not exceeded for fuel reaching the regulation area outsides in all considered test-cases. The simulations gave new insights on when and where the regulation area boundaries are reached and to which extend the simulated plume area and regulation area differ depending on the atmospheric conditions. A first appraisal of these differences showed that in most of the simulated cases the blocking volume prescribed by the regulations could be reduced by more than 70% without overstepping identified threshold fuel concentrations. The results motivate further investigations on this topic and future optimization efforts to assess potential benefits for air traffic management.