Combined Analytical and Experimental Approaches to Rotor and Dynamic Component Stress Predictions

The USN engineering community recognizes the advantages of individual component damage tracking with the goal of enhancing health assessment capabilities. Improving individual aircraft loads/strain predictions is an important focus of this objective. TDA has developed the software tool rotorwiseTM, a method to combine analytical modeling and experimental data to improve the accuracy of predictions for individual blade loads and stresses in dynamic components. Direct loads-based usage tracking for fatigue-critical rotorcraft dynamic components provides insight into the actual load history of the component in question, offers the potential to extend component service life, and allow for part remediation through the acceptance of greater repair limits. It can also prevent unnecessary maintenance actions, such as early component retirement, enhancing mission readiness and reducing maintenance costs. This presents the possibility for significant maintenance cost savings, as well as enhanced awareness of component structural health. rotorwiseTM takes as input a combination of instrumentation, on-board data processing requirements, offline data collection, numerical rotor loads analysis, and fatigue life prediction algorithms. rotorwiseTM supports the USN's end goals for the CH-53K: tracking rotorcraft life in near real-time, gathering complete component loads/usage history, and thereby accurately predicting the life of each system. This eliminates penalties imposed due to unknown usage histories and/or inaccurate/overly-conservative loads prediction.