Abstract: In order to improve the veracity and effectiveness of the early fault detection,the method of early detection method of weak fault signals with multi-character frequencies was proposed through array scan,by employing cross-correlation for denoising and building chaos oscillators array.In this method,the denoised signals were sent to the chaos oscillator detection array to act as a part of the chaos detection system's periodical driving force,and then the weak fault signals could be detected from the system's phase locus change.Its feasibility is verified by the example of an aircraft rotor system's early rub-impact fault detection.