Cyclostationary-based tools for bearing diagnostics of helicopter planetary gearboxes

The components of a helicopter gearbox are vulnerable to fatigue defects and therefore Health and Usage Monitoring Systems have been developed, focusing towards early, accurate and on time fault detection with limited false alarms and missed detections. The main aim of HUMs is to enhance the helicopters' operational reliability and functionality and to improve flight airworthiness. A plethora of methods have been proposed in order to perform fault detection and diagnosis of gearboxes. IESFOgram has been recently proposed by the authors, based on Cyclic Spectral Correlation (CSC) and Coherence (CSCoh), focusing on the accurate selection of a filtering band for demodulation. The integration of CSC and CSCoh along the selected band leads to an Improved Envelope Spectrum. In this paper the performance of the tool is evaluated and compared to the literature on a dataset captured during an endurance test of a UH-60 Black Hawk helicopter main gearbox transmission.status: Published onlin