I'd question the validity of Spectrometric Oil Analysis in this case, since the affected areas we are talking about on the engines aren't part of the wet system. Also Borescopes are not the be all and end all.. far from it. Yes you can check parts of the combustion chamber, and you can also check the forst few compressor stages and one maybe two stages of the turbine if you are lucky, but the checks are a long way from being comprehensive
Fly3est,
I
didn't say Oil analysis
would be in this case.
No, 'scopes are not the be all and end all, i
didn't say they were either.
And it depends on the engine type what you can inspect, on the engines i have owned (all off wing from 737) have been able to inspect all the LPC, all the HPC and the T1 blades and disks. I have about 40 scope video on my shelf behind me, some of those engines I have owned some I have not.
As I said, what they enable is an understanding of what is going on, or rather, what has gone on in the engine without having to break it open and subject yourself to unnecessary maintence.
In the case of contaminant ingestion in this case, we know that damage can occur from the combustion chamber backwards and with the T1 operating higher than the material limits, as such a scope of the T section will provide an indicator of any damage due to contaminant ingestion.
I would rather scope an engine than not.