Safety Lessons Learned from International Programs Mir-NASA, ISS, ATV
Bezhko, A.; Vorobjov, P.; Smirnov, A.
The implementation of international programs MIR-NASA, ISS, ATV over the last decades has provided an invaluable experience in assurance of flight safety for space systems composed of elements made in different countries. This experience can be subdivided into three areas: - Generating safety requirements; - Interfacing between the partnerís safety organizations; - Safety certification for space system components and deliverable payloads/experiments. One of the most important factors in safety assurance is making sure that partners meet safety requirements. These requirements define the necessary tolerance to failures in the subsystems within the system in order to prevent critical and catastrophic situations, measures needed to recover from them, quantitative specifications for crew habitation environment parameters, reliability, safety factors, operating life, etc. Since some of the subsystems in the new system that have positive flight test results are heritage hardware from some other space vehicles developed by different partners, there is a need to coordinate the applicability of different countriesí standards. Such activities have been conducted in all the programs reviewed in the paper. They required a thorough analysis by specialists and mostly produced positive results. A number of difficulties arose in the course of the specific work during ISS assembly and operation, since safety requirements that would be common to all the partners have not been developed in time. The most efficient means of interfacing between the partnerís safety organizations turned out to be working groups that bring together all safety specialists and all areas of safety activities. Weekly working group telecons in MIR-NASA and ISS programs made it possible to address all issues, sometimes very urgent, in a prompt and timely manner. An important element of interfacing in the ISS program is also the multilateral safety panel for addressing central issues, which was, unfortunately, only set up when the space station was already in orbit. The process of safety certification for space station elements and deliverable payloads/experiments has been most fully developed on ISS. In spite of the lack of cargo and experiment certification process documents that are common to all the partners, common safety document formats (safety certificates, hazardous and non-hazardous cargo/experiment descriptions) and a common procedures for reviewing these documents have been developed and applied. An analysis of interfacing between partners in specific situations of design, manufacturing and operation of the above space systems allows to draw up proposals for safety assurance of future international missions. The most important of these proposals are: - Developing common safety requirements at the initial phase of the project development; - Publishing a document on the applicability of the partnersí standards; - Including into the project management structure at a phase while it is still being formed a multilateral safety panel; - Setting up permanent safety working groups that bring together all areas of the work; - Development of certification process for space system elements and deliverable payloads/experiments that will be common to all the partners; - Drawing up an international document on space flight safety assurance.