Retrofit blade controls of the type explored here can both enhance the performance and reduce the acoustic emissions and blade-induced vibrations of suitably equipped rotorcraft over baseline vehicles. Since this capability could be achieved using technology that does not require the re-blading of an existing helicopter, a significant commercial product improvement program for a variety of aircraft would be possible. Military operators would also realize improved mission capability and reduced aircraft downtime with these anticipated improvements. However, this actuation technology can also serve as a starting point for development of an evolved active control system that integrates the trailing edge active control devices into the blade structure, offering an alternative implementation path with potential advantages in robustness and reduced drag penalty. An adaptive ability to alter the spanwise loading of rotor blades could be used to optimize rotorcraft aeromechanics and identify improved operational profiles, maximizing the utility and cost-effectiveness of future helicopters incorporating this technology. Full development of this novel adaptive blade capability would support key aeromechanics aspects of the Subsonic Rotary Wing Project of the Fundamental Aeronautics Program, in particular active on-blade control for performance improvement and noise and vibration alleviation. Follow-on work would also enhance current analysis methods, which are presently unable to capture complex active-rotor response and thus are a barrier to selection of optimal active control approaches.
More »