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 This Master's Thesis develops a Monte Carlo framework for comparing two maintenance strategies under interdicted logistics conditions, illustrated through the CV90 infantry fighting vehicle: Strategy A (modular exchange), in which the entire failed module is replaced at a forward position, and Strategy B (component-level repair), in which only the faulty component inside the module is repaired. Logistic interdiction is represented by β and the physical footprint of the delivered item, which together determine the delivery-time function. β determines the expected number of delivery attempts required for a successful arrival, while the physical footprint determines the time cost of each delivery attempt. Transit time and transit distance are held constant between the strategies. The system contains five subsystems in series and is analyzed for a period of 30 days. Failures are assumed to occur according to a Poisson distribution, repair times according to a lognormal distribution, and delivery attempts according to a geometric distribution, whereby interdicted delivery attempts imply new delivery attempts. Owing to a lack of data specific to military platforms, civilian vehicle data are used as a proxy. Thus, β* (the intersection of Strategy A and Strategy B) needs to be regarded as an illustrative threshold under proxy conditions, and not as an actual platform-specific threshold for the CV90.

The results show that Strategy A provides higher operational availability (Ao) than Strategy B across most of the tested threat range. In the case of baseline values, Strategy A and Strategy B yield equal Ao at β* ≈ 0.80, corresponding to an expected five delivery cycles per successful arrival under the modeled geometric retry process. If the repair duration for both strategies is stressed to k_repair = 1.5, β* becomes approximately equal to 0.87. Considering the fact that Strategy B has longer baseline repair times, the same multiplier imposes a larger absolute repair-time burden on Strategy B. A supplementary hybrid strategy, which implies choosing the better strategy in each subsystem separately, surpasses both pure strategies in Ao only in a narrow window near the crossover point. 

The research demonstrates how maintenance depth in relation to logistics interdiction may be considered as a stochastic availability issue, linking repair strategy, logistical footprint, interdicted delivery attempts, waiting time, and Ao together.