Methodological instrumentation of the sign of the sustainability at the selection of the functioning of the constructive elements of the aircraft

The article considers the issues of safety assessment of structural elements of aircraft. The degree of observability of those parameters or indicators that will allow us to judge the current state of the aircraft and its constructive elements for analyzing and forecasting the quality of its operation, making decisions and selecting control actions largely depends on the informativeness of the aircraft’s subsystems (VS). The authors believe that the organization of life cycle monitoring of the aircraft begins with the selection of the monitoring purpose and the signs determining its purpose and condition.