Abstract
To analyze the crash characteristics of a typical large aircraft fuselage section and occupant injury, a three-frame typical fuselage section was designed and fabricated, which including two sets of triple seats and four 50th-percentile FAA Hybrid III Anthropomorphic Test Devices (ATDs). The vertical drop test of fuselage section was conducted at 6.02m/s, the crash response and occupant injury were analyzed, and the crashworthiness evaluation and analysis of fuselage section were further conducted. The results show that the sub-cabin floor structures suffer the serious deformation and damage, which is the unrolling failure mode (three plastic hinges failure mode), and one opening plastic hinge is generated in the sub-cargo middle support columns area, and two opening plastic hinges are generated in the connection areas between the both sides cabin floor support columns and fuselage frames. The cabin area is remained basically intact, and the survivable volume is maintained. The connections between the seats and cabin floor guide rails are maintained in good condition, and the occupant seat belts are kept in place. The maximum value of head injury criterion and lumbar spine compression load are 31.47 and 3997.2 N, respectively, which are much lower than the threshold of Airworthiness Standard. The ATDs lean towards the aisle, and the occupant egress paths are maintained. The aircraft crashworthiness is evaluated by considering the survivable volume, retention strength, occupant injury and emergency evacuation, and the Integrated Crashworthiness Index (ICI) is used to evaluate the aircraft crashworthiness by the scoring method, which indicating a low occupant injury risk. The flattening failure mode (multiple plastic hinges failure mode) of fuselage section can be realized by controlling the failure load, failure position and failure sequence of fuselage section, and more crash energy can be absorbed by producing multiple plastic hinges of fuselage section, which can effectively improve the crashworthiness of fuselage section.