Which level of maintenance is primarily responsible for maintaining mission-capable readiness?

The level of maintenance that is primarily responsible for maintaining mission-capable readiness is O-Level Maintenance. This level of maintenance is conducted by the operating forces and is essential for ensuring that equipment is available and operational in support of mission requirements. O-Level Maintenance includes routine inspections, servicing, and minor repairs to ensure that systems and subsystems are functioning effectively, which directly impacts the units' ability to perform their assigned missions.

O-Level activities also encompass the management of maintenance actions and the documentation of equipment status, critical to maintaining readiness. This focus on immediate, frontline maintenance helps prevent equipment failures during operations, ensuring that the necessary capabilities are available when needed.

Other levels of maintenance, although vital for the overall maintenance strategy, do not primarily focus on the continuous readiness of mission-capable assets. Each level has its specific roles: Depot Level Maintenance typically handles extensive overhauls and repairs beyond the scope of regular operations, while I-Level Maintenance is responsible for intermediate repairs, calibrations, and component replacements that support O-Level units but may not be directly involved in day-to-day mission readiness. Field Level Maintenance generally involves actions taken in immediate operational settings but often falls under the broader definitions of O-Level responsibilities in many contexts.