Considering the coupling effect of intershaft bearing and the influence of gyroscopic moments

a dynamic model of a dual-rotor-ball bearing coupling system under maneuvering flight was established by using Lagranges equation

whilst theoretical and experimental study were both carried out. It is shown that with the increase of speed ratio of inner and outer rotors

the vibration amplitude decreases and the speed of bifurcation point grows with a maximum rate about 67.49%. The rotors vibration amplitude increases and more frequencies appear under maneuvering flight. With the increase of leaping flight speed

the outer rotors vibration amplitude increases obviously with a maximum rate about 409.24%

the speed of bifurcation point grows at the same time. During rolling flight

the rotors period doubling bifurcation point disappears in contrast to the system without maneuvering flight

but the vibration amplitude increases obviously. By using a model experiment rig of a dual-rotor system under maneuvering flight

parts of dynamic characteristics of outer rotor have been studied

and the experimental and numerical simulation results are in good agreement.