In this study, we evaluate rules of allocation and planning factors that have an effect on requirements for Army air ambulance companies. The Army uses rules of allocation In scenarios drawn from strategic planning documents to determine how many units of each type are required. Army planners use these rules for determining the number of units required to support specific operational and tactical scenarios. Unrealistic rules result in unrealistic unit requirements. We evaluate quantitatively (via Monte Carlo simulation) planning considerations for air ambulance units during major combat operations (MCO) and estimate that 0.4 airframes per admission would be a reasonable planning factor.