Performance and Flying Quality Analysis of a Fan-in-Body Compound Rotorcraft in Transition Flight

In this paper, a design for a fan-in-body compound rotorcraft with tandem ducted fans, wings, and two pairs of tractor propellers is proposed. It operates either as rotorcraft or a fixed-wing aircraft. This paper presents initial results on the performance characteristics and flying qualities of the fan-in-body compound rotorcraft in transition flight. A flight simulation model of the fan-in-body compound rotorcraft was developed. The power required for various settings of the flap angle, fuselage attitude, and control allocation were evaluated for further analysis of transition flight. Longitudinal axis and lateral/directional SCAS controllers were designed. Flying qualities were evaluated for the aircraft with control allocation in forward flight using CONDUIT. The evaluation index was decided through ADS-33 and MIL-STD 1797A. Robustness analysis was performed by applying a random perturbation to the state variables and control inputs, and the robustness of the control input allocation algorithm was verified.