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Flight dynamic simulation of helicopter forward flight through microburst wind field

A nonlinear dynamic model of a helicopter flying through a variable microburst wind field is developed. Equivalent wind field models are established based on the Soesman and gust models to analyze quantitatively the abrupt change when a helicopter enters and leaves the wind field. The comparison of the simulation results with and without the equivalent model shows that the equivalent model has good accuracy for flight dynamic simulation of a helicopter under atmospheric disturbance. Real-time simulation of helicopter forward flight through the microburst wind field is also conducted at different positions and heights to analyze the influence of wind at the side direction and the downward flow on helicopter flight performance. The results indicate that wind at the side direction enables the helicopter to carry out complicated lateral movements with different yaw characteristics. Furthermore, with the increase in flight height, the downward flow leads to faster rate of descent and stronger vertical overload, both of which will affect the flight safety of the helicopter.