CS 27.549 Fuselage, landing gear, and rotor pylon structures

• ED Decision 2023/001/R found in: CS-27 Amdt 10 - Small Rotorcraft (Feb 2023)
• ED Decision 2012/021/R found in: CS-27 Amdt 9 - Small Rotorcraft (Dec 2021)

CS 27.549 Fuselage, landing gear, and rotor pylon structures ED Decision 2023/001/R (a) Each fuselage, landing gear, and rotor pylon structure must be designed as prescribed in this paragraph. Resultant rotor forces may be represented as a single force applied at the rotor hub attachment point. (b) Each structure must be designed to withstand: (1) The critical loads prescribed in [CS 27.337](#_DxCrossRefBm8893833) to [27.341](#_DxCrossRefBm8893836) and [CS 27.351](#_DxCrossRefBm8893814); (2) The applicable ground loads prescribed in [CS 27.235](#_DxCrossRefBm8893816), [27.471](#_DxCrossRefBm8893858) to [27.485](#_DxCrossRefBm8893864), [CS 27.493](#_DxCrossRefBm8893863), [27.497](#_DxCrossRefBm8893871), [27.501](#_DxCrossRefBm8893872), [27.505](#_DxCrossRefBm8893873), and [27.521](#_DxCrossRefBm8893874); and (3) The loads prescribed in [CS 27.547(c)(2) and (d)](#_DxCrossRefBm8893852). (c) Auxiliary rotor thrust, and the balancing air and inertia loads occurring under accelerated flight conditions, must be considered. (d) Each engine mount and adjacent fuselage structure must be designed to withstand the loads occuring under accelerated flight and landing conditions, including engine torque. [Amdt 27/3] CS 27.549 Fuselage, landing gear, and rotor pylon structures ED Decision 2012/021/R (a) Each fuselage, landing gear, and rotor pylon structure must be designed as prescribed in this paragraph. Resultant rotor forces may be represented as a single force applied at the rotor hub attachment point. (b) Each structure must be designed to withstand: (1) The critical loads prescribed in [CS 27.337](#_DxCrossRefBm472493268) to [27.341](#_DxCrossRefBm472493270); (2) The applicable ground loads prescribed in [CS 27.235](#_DxCrossRefBm472493258), [27.471](#_DxCrossRefBm472493289) to [27.485](#_DxCrossRefBm472493295), [CS 27.493](#_DxCrossRefBm472493294), [27.497](#_DxCrossRefBm472493302), [27.501](#_DxCrossRefBm472493303), [27.505](#_DxCrossRefBm472493304), and [27.521](#_DxCrossRefBm472493305); and (3) The loads prescribed in [CS 27.547(c)(2) and (d)](#_DxCrossRefBm472493306). (c) Auxiliary rotor thrust, and the balancing air and inertia loads occurring under accelerated flight conditions, must be considered. (d) Each engine mount and adjacent fuselage structure must be designed to withstand the loads occuring under accelerated flight and landing conditions, including engine torque. [Amdt 27/3]