This paper contains a study of helicopter rotor noise generated during maneuvering flight. In particular, the study focuses on the significance of noise generated during the transient states of a maneuver. Two elementary maneuvers, acceleration and a right turn-entry maneuver, are presented and analyzed. These maneuvers demonstrate that transient maneuver noise can be a dominant source of rotor noise. The acoustic impact of Blade-Vortex Interaction (BVI) and its role in the generation of transient maneuver noise is also analyzed in the right turn-entry maneuver. This study investigates the sources of transient maneuver noise by analyzing the acoustic effects of helicopter dynamic and aerodynamic response during transient maneuvering flight. By introducing a series of fictitious test cases, the sources of transient maneuver noise can be identified and the resulting change in acoustic signature is characterized by isolating the mechanisms believed to be responsible for generating the extra noise. It is found that the unsteady characteristics of rotor aerodynamics and dynamic response play a major role in generating transient maneuver noise.