This paper investigates negative imaginary system theory based control solution for the position and attitude control problem of 3 degrees of freedom (DOF) helicopter system. The 3 DOF helicopter is a benchmark laboratory model and it demonstrates open-loop unstable dynamics. Moreover, this systems also faces uncertainty because of coupling between its roll angle and travel rate. The control of such complex aero-dynamical system has been a challenging task for the control community. The article adopts a newly developed negative imaginary feedback control concept. The main objective of the paper is to apply negative imaginary theory based positive feedback control scheme to obtain the desired attitude (elevation angle, roll angle) and position (travel rate) as the outputs of the helicopter systems. The robust properties of the feedback system are demonstrated and simulation results of the paper show that stability and tracking property can be accomplished at the same time.