Rotor Load and Health Monitoring Sensor Technology

The Sikorsky Aircraft Corporation and the U.S. Army Aviation Development Directorate - Aviation Applied Technology Directorate jointly sponsored the Capability-Based Operations and Sustainment Technology-Aviation (COST-A) program. The objective of COST-A was to develop and demonstrate an integrated set of high-value diagnostics, prognostics, and system health management technologies for six different rotorcraft systems with a focus on reduced maintenance burden without sacrificing safety. One focus of the COST-A program was the rotor system because of the maintenance associated with life limited, flight critical components that are not directly monitored by existing rotorcraft Health and Usage Monitoring Systems. Operators must rely on numerous inspections to determine condition and ensure airworthiness, resulting in significant maintenance burden, both scheduled and unscheduled. The COST-A program developed and matured a number of prototype rotor sensors and diagnostic algorithms that can measure key global rotor loads, detect and characterize blade impact events, and monitor the health of high-value rotor components. Many of these technologies were developed to include the capability for wireless communication and self-powered operation. This paper focuses on rotor loads and health monitoring technologies and the results from full-scale UH-60 main rotor whirl demonstration tests.