Modelling and analysis of tiltrotor aircraft flight dynamics based on numerical simulation

Abstract

Development of electronic technology especially on flight controller-related aspect and engine technology which can generate more thrust with relatively small size encourage development of aircraft design to reach boundary. For a long time, fixed wing aircraft needs long runway to achieve its lift-off velocity hence the take-off phase is able to be continued by climbing and other flight phases. However, the tiltrotor configuration aircraft which is equipped with reliable flight controller can reduce the length of the runway by changing the thrust direction which is commonly fixed towards the body axis. In this research, the authors attempt to analyze the flight dynamics behavior in transition mode by discretizing the transition mode to several pseudo-cruise flight configurations. The analysis is started by calculating the pseudo-cruise flight condition for several flight configurations based on analytical calculation and then, compared to trimming and linearization results in numerical simulation platform. After knowing the pseudo-cruise flight configuration by trimming the aircraft, the dynamics stability of the aircraft is obtained for several tilting angles of engine. The aircraft model is limited to 3 DoF non-linear model to represent the behavior of the aircraft. The results show that analytical and numerical calculations have similar trend and tendency in pseudo-trim condition. Afterward, the selected aircraft is concluded as unstable system in all variations.