Thermal investigation of real aircraft components

Composite materials are prone to various damages, particularly if used for aeronautic fuselage components. These parts are increasingly used for civil and military aircraft. Internal defects, invisible on the surface, are detectable by means of different NDT methods, having individual advantages and drawbacks. Here, potentialities of IR Thermography are explored to detect and characterize delaminations and internal cracks on an aircraft door made of composite materials. The non-planar surface of the component has a varying thickness. A detailed study of the defect maps given by different data reduction algorithms is oriented to the design of a fast procedure suitable for an in situ application. In particular, the critical parts of the doors are tested on both sides in reflection and transparent mode. The reliability and quality of results is evaluated comparing thermography with data obtained by different methods as Ultrasounds and Mechanical Impedance. Experimental results show great effectiveness of thermography especially using pulsed techniques and phase analysis.