15/11/2018
The reliability growth process, applied to a complex
system under development, involves surfacing failure modes,
analyzing the modes and their causes, and implementing
corrective actions (fixes) to detected failures. In such a
manner, the system reliability is grows and its configuration is
going to be mature with respect to reliability. The
conventional procedure of the Reliability growth implies
evaluation of two principal parameters of the Non-
Homogeneous Poison Process (NHPP) related to the failure
rate only. In addition to the Reliability aspect, the Availability
factor, and, as the result, the Availability growth (not only
Reliability growth) is extremely important for many systems.
Yet because the standard NHPP does not take into account the
repair rate parameters, the practitioners are awaiting for a long
time for an expanded procedure for the Availability Growth
tracking. This paper suggests a model and a numerical method
to evaluate these parameters, establishing consequently the
Inherent Availability Growth model, i.e. considering only
corrective maintenance time due to failures. The model can be
further generalized for Operational and Achieved Availability
by taking in account the preventive maintenance,
administrative and logistics times as appropriate.