For many years Pratt & Whitney (P&W) has developed and leveraged advanced analytical methods and instrumentation technologies to ensure the health and safety of gas turbine engines.  In the last decade, working with the Defense Advanced Research Projects Agency (DARPA), the United States Air Force (USAF), United States Navy (USN) and academia, P&W has extended these capabilities to enable a structural prognosis and engine health management (SPHM) system for fielded systems.  SPHM is an integrated family of technologies that will allow P&W and operators of P&W products to monitor the health and remaining capability of engines based on the actual and planned future usage of each engine. 
One area of significant interest to P&W and P&W customers is in the prevention of high cycle fatigue related airfoil fractures in the fan and compression systems of aircraft gas turbines. Key to that system is the integration of advanced sensors with physics-based models that capture the airfoil material behavior and structural dynamics.  Key building blocks of the integrated prognosis system have been successfully developed on part bench and component spin tests, with demonstration and validation of the integrated system on full-up engine tests under the DARPA Engine Systems Prognosis (ESP) program.