Life Distributions and Degradation for A 2-Out-Of-n:F System

A 2-out-of-n:F system with exponential failure and Erlang repair times is considered; the probability density function for the time-to-system-failure (T) is exhibited and the probability generating function for the number of degradations (i.e., subsystem failures which are not essential to system operation) occurring during (0, T) is derived. Numerical results are also presented.