Study On Civil Aircraft Engine Pylon Emergency Breaking Away Simulation Method

Engine pylon is one of the most important components of large civil aircraft, playing an essential role in structure connecting and load bearing. And it is also a key part for aircraft crashworthiness design. When faced with urgent situations, pylon emergency breaking away techniques can be effective ways to protect passengers from fire and explosions caused by wing tank damage. Therefore, a systematic study on pylon emergency breaking away techniques with considering the structure design requirements and airworthiness regulations is quite necessary for the pylon’s design and validation tests.The engine pylon of a domestic civil aircraft is chosen as the research target, by analyzing its structure and load transmitting characteristics, some feasible breaking away measures are decided. Typical emergency landing conditions and flying parameters are worked out by reference to the airworthiness regulations and related research materials, and a full sized engine-pylon-wing finite element model is established. By conducting the simulations of different landing and impacting conditions, dynamical responses and separation status of the pylon are obtained.Based on the preliminary analysis, some main factors that affects the pylon’s separation are found out. By adjusting the arrangements of the fuse pins and recomputing, reasonable pylon separations for belly landing with small pitch angles and dead-stick landing are achieved. And two water landing conditions are analyzed to test the applicability of the adjusted pin arrangement. At last, further measures to improve the modeling method and get better pylon separations are discussed based on a comparative analysis of all the simulation results.The proposed dynamical modeling method along with the emergency landing parameters and simulation results can give certain reference to similar studies, pylon structure design and validation tests.