Analysis of the flight dynamics equilibrium characteristics of helicopter emergency flotation configuration

Abstract This study focuses on the flight test design for helicopter emergency flotation systems, and conducts modeling and simulation analyses of post-inflation deployment flight dynamics characteristics. First, CFD software is employed to compute the aerodynamic characteristics of the fuselage in both the deployed and folded states of the flotation airbags, thereby obtaining the corresponding fuselage aerodynamic data. Subsequently, a flight dynamics model of a single-rotor with a tail rotor helicopter in the emergency flotation configuration was established in Simulink. The Simulink Linear Analysis Tool was then employed to simulate and analyze the equilibrium characteristics of the helicopter under various flight conditions after the flotation airbags were deployed. Finally, the influence of the emergency flotation configuration’s aerodynamic characteristics on the pitch inputs and attitude angles required for stable flight following airbag deployment was summarized.