Abstract: With the increasing of space environment debris, the probability of spacecraft leakage increases significantly due to debris collision, which will inevitably affect the operational life of spacecraft in orbit. It is urgent to study the impact of ultrasonic spectrum of in-orbit leakage. Therefore, this paper focuses on studying the influence law of detection distance, sensing range, detection direction, mobile detection and multilayer on the ultrasonic spectrum characteristics of different leaks. The results show that the airborne leakage ultrasonic leak detection method can detect leakage hole of Ф0.3mm, the detection distance is up to 500mm, the detection direction angle is within ±30°, the characteristic frequency has main peak between 37-43kHz, the mobile inspection positioning accuracy is up to within ±20mm. The multilayer cladding layer has a complex impact on detection, the larger the cladding area, the lower the detection sensitivity and intensity. The research results have certain universality, it could provide technical support for the subsequent implementation of in-orbit leakage plugging measures.

Key words: in-orbit leakage, ultrasonic spectrum, detection distance, perception range, multilayer influence