MAINTENANCE SOURCING, FLEET AVAILABILITY AND HUMANITARIAN PREPAREDNESS: A 48-MONTH BRAZILIAN MILITARY CASE
This study examines changes in fleet availability and a recorded unit-cost indicator following the transition of vehicle maintenance from an external contractor to an organic Brazilian Air Force maintenance unit, with particular attention to implications for humanitarian preparedness. The analysis covers a 35-vehicle fleet over 48 months, comprising equal 24-month periods before and after the January 2023 transition. Monthly availability, target attainment, and inflation-adjusted unit-cost data were assessed descriptively and through exploratory segmented regression with Newey–West standard errors; monetary values were converted to December 2024 Brazilian reais using the national IPCA consumer price index. Mean fleet availability increased from 62.4% in 2021–2022 to 81.1% in 2023–2024, while the proportion of months meeting the 70% availability target rose from 37.5% to 79.2%. The mean IPCA-adjusted recorded unit-cost indicator was 20.9% higher in the post-transition period. However, because availability was already improving before the transition, segmented regression identified no statistically significant level or slope change attributable to January 2023. Availability nevertheless averaged 85.9% and remained above the 70% target from May through December 2024, coinciding with a period of major flood-response and recovery activities. These findings should therefore be interpreted as descriptive rather than causal. The absence of a comparison fleet, reliance on aggregated monthly data, potential concurrent organizational changes, limitations in cost comparability, and the lack of utilization and mission-output measures constrain causal inference. The study contributes to sustainment and humanitarian logistics research by showing how maintenance-sourcing decisions can be evaluated through mission criticality, asset substitutability, availability, and accounting comparability, while emphasizing that fleet availability represents only one component of broader operational and humanitarian response capacity.