ESP Adds New Dimension to Engine Health Prediction

  • Published
  • By Heyward Burnette
  • Materials and Manufacturing
WRIGHT-PATTERSON AIR FORCE BASE, Ohio --  Air Force Research 's transition of a Defense Advanced Research Projects Agency (DARPA)-developed system that calculates turbine engine component damage and facilitates accurate predictions of future engine health will cut costs and improve operational readiness and safety. Newly transitioned to Tinker Air Force Base, Oklahoma, the Engine System Prognosis (ESP) system provides unique technology to help manage premature component replacement, which is enormously expensive for the Air Force (AF). DARPA's new capability remedies this problem by enabling component-specific checks of engine bearing, hot gas path component, fan/compressor blade, and turbine disk health. Though especially relevant for older engines, the system is nonetheless applicable to today's advanced engines as well.

Aircraft engines are one of the AF's major assets. As such, replacing/discarding their myriad components before they have actually expired constitutes a huge--and often unnecessary--cost, both in terms of resource usage (i.e., time) and in dollars spent towards the purchase of new parts.  The capacity for aircraft maintainers to correctly, confidently predict engine component life will greatly reduce these costs--and with no sacrifice either to personnel well-being or to mission preparedness.

The ESP architecture includes four software modules: fan and compressor airfoil high-cycle fatigue lifing, disk life-predictive methodologies, bearing damage sensing and lifing, and hot gas path component life prediction. As an example of the system's efficiency, the module for fan and compressor airfoil HCF lifing leverages information unique to the physical relationship between airfoil damage state and airfoil response; by coupling this case-specific data with a built-in damage accumulation mechanism, the technology enables safe engine operation in the presence of damage well above (i.e., greater than 50 times) the levels currently allowable.

DARPA's development effort focused on physics-based approaches to analyzing and predicting material failure-causing defects in the F100 and F110 engines. Having ultimately delivered to the AF an ESP unit at Technology Readiness Level 6, the team has produced a novel capability officially designated as achieving an advanced state of readiness.