Design and Simulation of Seats for Emergency Landing Conditions in Electrical VTOLs

Abstract

Emerging electrification technologies in aviation and recent advances drive the increased usage of electrical vertical take-off and landing (VTOL) air vehicles. Weight considerations are predominant due to the weaker powertrain and lower payload capacity. Moreover, most systems are automated, and there is no distinction between pilot and passenger seats anymore. Conventional aircraft seating typically exhibits excessive weight, necessitating the development of lightweight troop seats with simple designs and textile seat pans and backrests. This research focuses primarily on the design aspects of these lightweight troop seats. There are already guiding military standards and civilian codes for physical tests for passenger or pilot seats. Nevertheless, there needs to be a comprehensive document combining all of these and explaining how simulation tools can be practically used for the same purpose. Consequently, a generic design was generated based on the troop seat of military helicopters, which was then tested and simulated virtually by finite element analysis according to MIL-S-85510, CS27, and CS29 standards. After finalizing the static tests for forward, rearward, lateral, downward, and upward g forces on a 10-degree floor deformation in the longitudinal axis, implicit dynamic tests were conducted with loading in longitudinal and vertical directions as specified by the MIL-S-85510 standards. Then, hotspot analysis is made for stress interpretation. As a result, a near-optimum design was achieved with stresses 10% lower than the yield stress of the materials, which can be used on board an electrical VTOL.

Keywords

• Seat
• Design
• Analysis
• MIL-S-85510
• CS27
• CS29
• VTOL

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