Multi-modal method combining Nonlinear Acoustics with Infra-Red Imaging for reliable detection of flaws in aircraft

This project will be devoted to the development of novel multi-mode inspection equipment to allow multiple inspection elements to interrogate large areas of the aircraft in a single inspection pass. During this project we will design, produce and test an advanced prototype using Nonlinear Acoustic (NA) modulation technique combined with Infra-Red (IR) Imaging (IRI) of cracks and other flaws in large areas of aircraft such as wings splice joints or fuselage splice joints. Both techniques have a great potential for microcracks/corrosion detection and localization, even if taken separately. We, however, propose to develop a combined NATIRI technique, which will take the advantages of both methods.  The Phase I research effort will demonstrate the feasibility of the proposed nonlinear acoustics and IR imaging techniques and supporting models. We will also produce first generation instrumentation and data processing techniques that will become the foundation of a cost effective and field-friendlyEproduct for the nondestructive inspection (NDI) of aircraft. Developed NAIRI equipment will be able to detect subsurface cracks 0.100Esize with 90% or higher PoD and will allow multiple inspections to be completed in the same amount of time as conventional single mode inspection. BENEFIT: While the research is expected to satisfy Air Force evaluations of aircraft materials, the same application would support the evaluation of other DoD platforms including naval vessels, ground vehicles and support machinery.  The proposed multi-modal novel technology will have broad civilian applications in the assessment of the structural integrity of materials, immediately following assembly, and during the operational life of the material.