Hi All
I used to be an authorised boroscope inspector on RB211 core, CFM56 and GE90 engs.
All are pretty similar in what you inspect for, ie compressor blades and gaspath, combustion chambers etc, but also fuel spray nozzles and domes as well as metering panels. I inspected a few 211s and grounded a few after finding faults with them (A couple of bad eng failures in flt including the 747 out of Buenos Aires led to a fleet check).
As mentioned before, you also look at turbine blades and nozzle guide vanes etc as well. All limits for damage is contained in the MM although to some degree it can all be down to the individual's interpretation of the damage. It was always best to get a second opinion if in question, but my former employer started trying out a new fangled invention to measure crack lenghths etc with digital camera equipment linked to a portable PC to carry out image processing to find out lenghts determined by cursor points. (Works only if you hold the camera tip at90 degrees to the damage.)
Anyway, I'm flying them now, and know whats inside the motors, what am I doing!!!????
Regds
[This message has been edited by spanners (edited 28 December 1999).]