Selected approaches on reliability assessment of complex system with one shot items

This paper deals with the modelling and analysis of the reliability of complex systems that use one-shot items during their operation. It includes an analysis of the impact of the reliability of used one-shot items on the resulting reliability of the system as a whole. Practical application of the theoretical knowledge is demonstrated using a model of reliability of an aircraft gun that was used for optimization of the gun’s design during its development and design. Furthermore this paper demonstrates utilization of a proposed model to determine an optimum number of pyrotechnic cartridges that will achieve a required probability of fulfilment of the mission with the given reliability of individual subsystems of the gun, rounds and pyrotechnic cartridges. The proposed procedures of modelling and analysis of the reliability of complex systems with oneshot items were used in practice in designing and development of the PL-20 aircraft gun. Development of the gun was successfully finished in 2005, and the gun was fielded in the armament of the Czech Republic Air Force.