“…Nevertheless, in propelled rotating machines, the most common on field-operating system fault is due to a damage on the propeller (or blade) body, see for instance [Shajiee et al, 2014;Oberholster and Heyns, 2006;Abdelrhman et al, 2013;Abdelrhman et al, 2012;Zeng et al, 2019]. Even when there exit many statistical methods on fault diagnosis based on data analysis, such as deep learning [Helbing and Ritter, 2018], Kalman filtering theory [Cho et al, 2018], bi-stable stochastic resonance theory [He et al, 2019], fuzzy logic and intelligent systems [Kuo, 1995], etcetera, we can still invoke fundamental statistical tools, like box-plot diagrams, for fault diagnosis to propeller rotating machines.…”