PPRuNe Forums - View Single Post - Air NZ 787 RR engine issues
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Old 18th Dec 2017, 15:27
  #63 (permalink)  
lomapaseo
 
Join Date: Mar 2002
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Mostly agree
but;

taking other's posts into account I'm not sure there is agreement what area of the engine is the one wearing out. Setting aside the original title of the thread, which unfortunately refers to a specific airline's flight. I only offer a general comment on the mysteriously sourced photos above. That damage as seen, appears to be secondary to something coming loose upstream in the turbine. It could very well be in stages that are coated.

As such while the gas temperature may be very high compared to melting points, the metal temperature itself is expected to be much cooler due to cooling air. So the idea of the coating is to provide an erosion barrier between the gas and the susceptible metal underneath the coating.

In this case discussions need to be careful about direct comparisons between engine gas temperatures and bulk metal melting temperatures.
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