This paper presents a highland atmospheric turbulence model for helicopter flight simulation. First, a spectrum model and statistical parameters of atmospheric turbulence velocity are provided considering the influence of highland topography, atmospheric stability, and mean wind speed profile. High-order shaping filters are developed by the least-square curve fitting method, and the zero-pole matching method is used to discretize the filters to form recursive algorithms for time-domain turbulence components. On this basis, spatially correlated atmospheric turbulence shaping filters are established by linear transformation with the Cholesky factorization of the covariance matrix. The "frozen field" hypothesis is used to expand the turbulence components along the direction of airspeed to form a three-dimensional atmospheric turbulence field covering all helicopter aerodynamic surfaces. Finally, the turbulence model is integrated into a helicopter flight dynamics model for flight simulation and validation against flight test data. The results show that the proposed turbulence model can accurately capture the influence of highland topography, atmospheric stability, and wind speed profile on the statistical characteristics of the atmospheric turbulence components. The integrated turbulence and flight dynamics model can accurately model the helicopter frequency response to atmospheric turbulence.
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