Maintenance of DoD's weapon systems and mission support assets (i.e., materiel maintenance) is a critical element in the readiness and sustainability of combat forces. The distribution of maintenance workloads among the public and private sectors is instrumental in maintaining a robust and viable industrial base. DoD's materiel maintenance operations support a wide range of weapon systems including about 280 ships, 14,000 aircraft/helicopters, 900 strategic missiles, and 30,000 combat vehicles.

DoD maintenance is accomplished by two different yet complementary components — depot-level and field-level maintenance activities. The two components are distinguished largely by their relative capabilities, flexibility, agility, and capacity.

Depot-level maintenance entails materiel maintenance requiring the major repair, overhaul, or complete rebuilding of weapon systems, end items, parts, assemblies, and subassemblies; manufacture of parts; technical assistance; and testing. Each military service manages and operates its own organic depot-level maintenance infrastructure. The bulk of the workload — about three quarters — is associated with ships and aircraft. Aircraft work amounts to more than half of the overall total while ship work accounts for about a third. The remaining work includes missile, combat vehicle, tactical vehicle, and other ground equipment system workloads. For FY2007, DoD estimates it will spend nearly $27 billion for depot-level maintenance and repair work. Approximately 53 percent of the Department's FY 2007 depot-level workload is planned to be accomplished in organic facilities; the remainder will be done in the private sector — by commercial firms.

Field-level maintenance comprises shop-type work as well as on-equipment maintenance activities at maintenance levels other than depot. Intermediate or shop-type work includes: limited repair of commodity-oriented assemblies and end items (e.g., electronic “black boxes” and mechanical components); job shop, bay, and production line operations for special requirements; repair of subassemblies such as circuit boards; software maintenance; and fabrication or manufacture of repair parts, assemblies, and components. On-equipment or organizational maintenance is normally performed by an operating unit on a day-to-day basis to support operations of its assigned weapon systems and equipment. Organizational maintenance encompasses a number of categories, such as inspections, servicing, handling, preventive maintenance, and corrective maintenance. Although no set of financial management systems captures the total cost of field-level maintenance, it is currently estimated to be in the range of $54 billion annually.

Nearly 660,000 military (Active and Reserve Component) and DoD civilian personnel are involved in DoD maintenance operations. Of this total, the Department estimates that about 10 percent are federal civilian employees assigned as depot-level maintenance personnel; the remaining 90 percent accomplish field-level maintenance activities. In addition, several thousand private sector firms are engaged in performing maintenance — mostly depot-level — of DoD material.

This Web site serves as a repository for selected DoD maintenance information and data. Included are policy documents, plans and reports, historical trends and projections, public and private sector workload information, and links to defense and contractor Web sites.