To achieve a typical operating mode selection scheme， this paper conducts research on an adaptive cycle engine with fan on blade （FLADE）. Based on the principles of aerodynamic thermodynamics of each component， a complete machine calculation model for this configuration with triple bypass mode is established on the MATLAB/Simulink platform. On the basis of this model， the performance of this configuration under different typical operating conditions of two working modes during the throttling process is analyzed by reducing iterative and residual variables. The simulation results show that under ground operating conditions， the triple bypass mode has higher thrust at low speed compared with the single-add-third bypass mode， while at high speed it is the opposite. The single-add-third bypass mode can be used for take off under high-power ground conditions， and for subsonic cruise conditions with low thrust requirements， the mode selection valve （MSV） can be activated to operate the engine in triple bypass mode after the aircraft climbs during the phase.