The S17 and EGV issues was a hot topic many years back. The OEM recommended inner barrel bore plugs and software protection to avoid vortex bursting of the last stage stators. Is this still an issue? Any users seen blade distress even after all of the TILs were implemented?

Good question, it must still be an issue since GE is offering the upgraded shrouded 17 segments, shorter EGVs in addition to a modified and larger diameter inner barrel to match. There is an aftermarket option out there which shrouds the S17 and shrouds the EGV which retains the existing inner barrel but requires machining to fit the new hardware. Has anyone see actual 17/EGV root cracking or even liberations?

Our borescope vendor inspects for S17 and EGV distress. I believe they look for stepping, tip rubs/curles, and gaps. I dont think it would be as visible to see fretting or base vane wear unless its significantly notable from platform stepping. I really like the shouded designs but havent heard much about S17/EGv issues after GE implemented the counter bore plugs and software logic upgrade.