On-board SHM System Architecture and Operational Concept for Small Commuter Aircraft

Significant R&D progress has been done in the area of SHM technologies in recent years. However real SHM application on aircraft board is still challenging and puts specific requirements on the SHM system design and operation. These challenges include assurance of reliable and provable damage detection capabilities, taking over decision-making responsibilities instead of a human inspector and other challenges related to on-board installation and operation during the flight. Further, minimal weight and dimension, and system reliability and durability should be considered. Due to these challenging requirements the SHM has not been widely implemented in aerospace industry yet. The paper deals with system architecture and operational concept of SHM system for L-410 NG commuter aircraft. The SHM system is based on excitation, sensing and analysis of ultrasonic guided waves using PZT actuators / sensors. The SHM system is designed for monitoring of PSEs of metallic airframe that are hard to access or completely inaccessible for common inspection methods used in the aircraft maintenance. The design puts emphasis on integration of the SHM system within aircraft avionic system in order to achieve highly automated data acquisition and data transfer process to make the health data available for on-ground analysis. Finally, scenario of the SHM system operation in accordance to the L-410 NG maintenance plan is proposed in the paper. The scenario assumes replacement of common inspections that are done within regular maintenance checks by the automated inspections using SHM system. Challenges of the proposed scenario from the point of view of the aircraft certification and operation are discussed as well. 1