Design of a sled test fixture for civilian helicopter seats

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2019
Seçgin, Alican
Crashworthiness of civilian helicopter seats are important since it affects the survivability of occupants. For this reason, there are some established criteria for the authorization of civilian helicopter seats. In this study, vertical crash criterion and floor deformation criterion, which are stated on CS 29.562 by European Aviation Safety Agency (EASA), regarding to civilian helicopter seats are investigated. The Simplified Helicopter Seat (SHS), the Interchangeable Floor Deformation Unit (IFDU), and Sled Test Fixture (STF) are designed and validated using bolt preload analyses, floor deformation analysis, and crash analyses. IFDU and STF are novel designs aiming to validate the civilian helicopter seats in terms of floor deformation effect and vertical crash criterion, respectively. Mapping technique is utilized for transferring the results of analyses among themselves. The bolt preload analysis and the crash analysis are investigated for SHS. IFDU is utilized for observing the effect of floor deformation when SHS is mounted to IFDU before the crash analysis of IFDU and SHS. The bolt preload analysis, the floor deformation analysis, and the crash analysis are investigated for IFDU. STF is designed to perform an analysis simulating the accelerating type sled tests. The crash loads representing the sled tests are applied to STF and the concluding results are discussed.

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Citation Formats
A. Seçgin, “Design of a sled test fixture for civilian helicopter seats,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Mechanical Engineering., Middle East Technical University, 2019.