Is familiar with the methodology of sample preparation for microstructural studies (specimens), and support for Leica optical microscope. Prepared zgłady blades - very responsible of engine airplane - the test is not marked on the strengthening and anti-corrosion layers. Studies have confirmed the presence of several layers, which could not be detected using a method of acoustic microscopy. Perhaps with such a thin (several micrometers) are undetectable to the acoustic microscope, despite attempts to use different types of heads and change measurement parameters.