Miniature trailing-edge effectors are segmented gurney flaps that can deploy to achieve multipurpose functions, such as performance enhancement, noise/vibration control, and/or load control on rotor blades. The unsteady aerodynamics of miniature trailing-edge effectors and a déployable plain flap (with an equivalent lift gain) are quantifled experimentally at a reduced frequency of 0.21 and a Reynolds number of 1 x lO". These experiments are also simulated using computational fluid dynamics. The combination of the wind tunnel experiments and computational fluid dynamics are used to quantify the aerodynamic effects of miniature trailing-edge effector deployment to compare their unsteady aerodynamics to plain flaps, and to evaluate the fluid dynamics of miniature trailing-edge effectors against experimental data. The current experiments display unsteady aerodynamics that corroborate previous computational fluid dynamics flndings that indicate that miniature trailing-edge effectors shed on-surface vortices during deployment, affecting the unsteady aerodynamics of the system. Computational fluid dynamics also predicted that miniature trailing-edge effectors require 1/55 power to deploy compared to a plain-flap configuration. Power reduction is a key attractor for the integration of de vices on smart rotors. This work is concluded with an effort that displays that the low power requirement of miniature trailing-edge effectors enable simple deployment methods, such as the use of pressure differentials inherent to the rotor blades. The proposed pneumatic miniature trailing-edge effector configuration was tested at centrifugal forces representative of helicopter rotor blades.Ci cf" (-norm Cf C CL CM

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The use of ultrasonic excitation has shown the ability to promote ice shedding of impact ice (<2 mm thick) during prior wind tunnel testing efforts. The ultrasonic deicing technology is implemented to structures representative of rotorcraft blade leading edges and tested under impact icing and centrifugal environments (390 gs). Finite Element Models (FEM) are experimentally validated and used to predict the ultrasonic ice shedding transverse shear stresses responsible for ice shedding. The FEM tools are then utilized to guide the design of an optimized bondline between the PZT actuators and the host structure forming the ultrasonic deicing system. The novel bondline approach is implemented to a rotor blade leading edge erosion cap representative structure (0.813 mm thick stainless steel leading edge). The system is tested under centrifugal loads and icing conditions generic to helicopter operational envelopes. Details on the optimized system fabrication and integration are provided. The optimized bondline configuration does not degrade during operation and increases the ice interface transverse shear stresses by 15% with respect to prior bonding approaches. To promote ice shedding of impact ice, a system control to identify and excite optimum deicing modes during rotor ice testing is also implemented and described in this paper. The power consumption of the deicing system is quantified to average 0.63 W/cm 2 . The deicing system is able to promote shedding of ice layers ranging from 1.4 to 7.1 mm in thickness for varying icing conditions within FAR Part 25/29 Appendix: C Icing Envelope.