Turbines that are housed in aircraft engines are subjected to pretty tough conditions. They must perform at speeds of 30,000 rpm in temperatures greater than 800ºC for hours at a time.

The engine manufacturers fully understand that even small surface defects can reduce performance, increase maintenance costs, and reduce the useful life of an aircraft engine. They need to inspect turbine blades very carefully to maintain the efficiency and reliability that the air transport industry requires.

One particular North American manufacturer inspected its blades by hand and human eye. The highly-trained inspectors measured hundreds of features and checked for surface defects that measured in thousandths of an inch. Manual inspection was not only costly in terms of time and labor, but subjective as well. Results were variable and even differed between inspectors. Because manual inspection was so time consuming, there was no systematic inspection of every blade, only samplings of blades were inspected. Clearly, the manufacturer required an approach that would allow systematic inspections of the blades, save time, and yield consistent and repeatable results.

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