J. E. Michaels, T. E. Michaels, Georgia Institute of Technology, Atlanta, GA; A. C. Cobb, Southwest Research Institute, San Antonio, TX
A robust ultrasonic method for in situ monitoring of fastener hole fatigue cracks was developed as part of the DARPA Structural Integrity Prognosis System (SIPS) program. Over the four years of the SIPS program, this ultrasonic method was applied to many coupon tests as well as three full scale fatigue tests. Both the ultrasonic method and the fatigue test results are summarized in this talk. The conclusion is that this method is viable for on-aircraft use, particularly when combined with a state estimation framework that merges ultrasonic measurement results with crack growth models.
Summary: A robust ultrasonic method for in situ monitoring of fastener hole fatigue cracks was developed as part of the DARPA Structural Integrity Prognosis System (SIPS) program. Over the four years of the SIPS program, this ultrasonic method was applied to many coupon tests as well as three full scale fatigue tests. Both the ultrasonic method and the fatigue tests results are summarized in this talk. The conclusion is that this method is viable for on-aircraft use, particularly when combined with a state estimation framework that merges ultrasonic measurement results with crack growth models.
