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Nowadays the composite material is becoming essential for aerospace structures due to the weight reduction. The lightweight composite structures bring with some problems like accidental damage. The support of Structural Health Monitoring (SHM) systems in overall Structural Integrity (SI) management in those cases is in continuous growth. Airbus Defence and Space is developing a SHM System able to diagnose acci-dental events/damages during aircraft operation to provide additional information for maintenance program application. In this paper it is presented the evaluation of this SHM system for a composite fuselage cockpit structure in the diagnosis of mechanical impacts (events) and resulting damages. The system has been applied to composite complex and large structure using the background knowledge of previous studies on composite reinforced flat panels. An analytic elastic wave propagation 2D/3D model for composite material structures supports the event and damage diagnosis. The results indicate the particularities of SHM diagnosis for events and damages in a real composite structure.

The Environmental and Operational Conditions (EOC) measurement and compensation in Structural Health Monitoring (SHM) systems for event and damage diagnosis during the aircraft operation is a key aspect to ensure their reliability. In addition, those EOC measurements can be used to support the existing usage and operational loads monitoring systems of Airbus Defence and Space (ADS), enhancing its capabilities.

In real aircraft structures the comfort and the occupational performance of crewmembers and passengers are affected by the presence of noise. In this sense, special attention is focused on mechanical and material design for isolation and vibration control. Experimental characterization and, in particular, experimental modal analysis, provides information for adequate cabin noise control. Traditional sensors employed in the aircraft industry for this purpose are invasive and provide a low spatial resolution. This paper presents a methodology for experimental modal characterization of a front fuselage full-scale demonstrator using high-speed 3D digital image correlation, which is non-invasive, ensuring that the structural response is unperturbed by the instrumentation mass. Specifically, full-field measurements on the passenger window area were conducted when the structure was excited using an electrodynamic shaker. The spectral analysis of the measured time-domain displacements made it possible to identify natural frequencies and full-field operational deflection shapes. Changes in the modal parameters due to cabin pressurization and the behavior of different local structural modifications were assessed using this methodology. The proposed full-field methodology allowed the characterization of relevant dynamic response patterns, complementing the capabilities provided by accelerometers.