Updated December 9, 2020
Defense Primer: Department of Defense Maintenance Depots
Title 10, United States Code (U.S.C.) §2464 states that it is
How do the Maintenance Depots support
“essential for the national defense that the Department of
readiness?
Defense maintain a core logistics capability that is
DOD’s maintenance depots are GOGO facilities that are
government-owned and government-operated [GOGO] ... to
capable of performing complete overhauls of military
ensure a ready and controlled source of technical
weapon systems, as well as repairs to many individual
competence and resources necessary to ensure effective and
components within each weapon system. Many of the
timely response to a mobilization, national defense
maintenance depots also have the ability to send mobile
contingency situations, and other emergency requirements.”
repair teams to operating locations to perform on-site
Accordingly, each military service owns and operates
technical assistance or in-depth repairs. As the Government
industrial facilities that manufacture, maintain, repair, and
Accountability Office (GAO) states in its 2019 report
overhaul military weapons and equipment. These GOGO
(GAO-19-242), these depots “are crucial to maintaining
facilities, together with certain government-owned,
military readiness by ensuring that the services can
contractor-operated (GOCO) facilities are collectively
regularly repair critical weapon systems and return them to
referred to as the organic industrial base, or OIB.
the warfighter for their use in training and operations.” The
maintenance depots also serve as a repository for technical
Included in the OIB are several large-scale maintenance
data, testing equipment, and unique tooling and design
facilities (otherwise named depots, shipyards, production
capabilities for many weapon systems.
plants, logistics complexes, or readiness centers) owned by
each service that are dedicated to performing depot-level
Organization and Management
maintenance and repair (collectively the “maintenance
Each military service includes command structures with
depots”). In addition, the Air Force and Navy utilize several
responsibility for providing logistics and maintenance
“centers” that perform weapon systems support in the forms
support to the majority of its weapon systems and
of research, development, test and evaluation (RDT&E),
equipment. Within each service, there are dedicated
acquisition, and sustainment activities including depot-level
maintenance depots whose primary responsibility is to
maintenance and repair. This InFocus pertains to those
conduct depot-level maintenance (Figure 1). However,
selected large-scale maintenance facilities that maintain,
depot-level maintenance can be performed at any location,
repair, or overhaul end items (See GAO-17-82R).
thus some facilities may not be identified as a maintenance
depot by DOD or other government agencies due to the
What is Depot-Level Maintenance?
scale or majority of work performed at that location.
Title 10 U.S.C. §2460 defines depot-level maintenance and
repair (commonly “depot maintenance” or “D-Level”
Figure 1. Selected DOD Maintenance Depot Sites
maintenance) as “material maintenance or repair requiring
the overhaul, upgrading, or rebuilding of parts, assemblies,
or subassemblies, and the testing and reclamation of
equipment as necessary, regardless of the source of funds
for the maintenance or repair or the location at which
the maintenance or repair is performed [emphasis added
by CRS].” The definition includes “(1) all aspects of
software maintenance classified by the Department of
Defense as of July 1, 1995, as depot-level maintenance and
repair, and (2) interim contractor support or contractor
logistics support (or any similar contractor support), to the
extent that such support is for the performance of services
described in the preceding sentence.”
Source: GAO-17-82R.
Section 2460 specifically excludes certain activities such as
“the procurement of major modifications or upgrades of
Note: The identification of maintenance depot sites has changed
over time (e.g., see the 2008 DOD Maintenance Fact Book). No sites
weapon systems that are designed to improve program
were identified in Alaska, Hawai , or the U.S. territories.
performance,” and the nuclear refueling or defueling of
aircraft carriers. Additionally, the procurement of parts for
Army
safety modifications is not considered depot maintenance,
however the installation of those parts is.
Army Materiel Command (AMC), headquartered at
Redstone Arsenal, AL, develops and delivers materiel
support to maintain combat equipment. AMC operates five
maintenance depots, each of which is generally responsible
for specific systems.
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Defense Primer: Department of Defense Maintenance Depots
Anniston Army Depot, AL: Combat vehicles, small
operates two production plants that perform depot-level
caliber weapons, artil ery, and rail operations.
maintenance.
Corpus Christi Army Depot, TX: Rotary wing
Marine Corps Logistics Base Albany, GA: Ground-
aircraft.
combat and combat-support equipment (East Coast).
Letterkenny Army Depot, PA: Air defense and
Marine Corps Logistics Base Barstow, CA: Ground-
tactical missile systems.
combat and combat-support equipment (West Coast).
Red River Army Depot, TX: Combat and tactical
Relevant Legislation: Maintaining a Core
wheeled vehicles.
Logistics Capability
Tobyhanna Army Depot, PA: Electronic systems.
Title 10 U.S.C. §2464 requires the Secretary of Defense, in
consultation with the Chairman of the Joint Chiefs of Staff,
Air Force
to identify the core logistics capabilities necessary to
Air Force Materiel Command (AFMC), headquartered at
maintain and repair the weapons systems and other military
equipment “as necessary to enable the armed forces to
Wright-Patterson Air Force Base, OH, conducts RDT&E
while also providing acquisition management and logistics
fulfill the strategic and contingency plans prepared by the
support. Under AFMC, the Air Force Sustainment Center,
Chairman of the Joint Chiefs of Staff under [10 U.S.C.
§153(a)].”
located at Tinker Air Force Base, OK, directs the operations
Section 2464 also requires the Secretary to
of the three Air Logistics Complexes (ALCs), each of
assign the maintenance depots “sufficient workload to
which generally performs work on specific weapon
ensure cost efficiency and technical competence in
systems.
peacetime while preserving ... surge capacity and
reconstitution capabilities.”
Ogden ALC, UT: Aircraft such as the F-35, F-22, and
The 50/50 Statute
C-130 as well as Minuteman III Intercontinental Ballistic
Missiles.
Title 10 U.S.C. §2466, often referred to as the 50/50 statute,
states that not more than 50% of the funds made available
Oklahoma City ALC, OK: Aircraft such as the B-1B
in a fiscal year to a military department or defense agency
and B-52 as well as military aircraft engines.
for depot-level maintenance and repair workload, may be
Warner Robins ALC, GA: Aircraft such as the F-15,
used to contract nonfederal government personnel for the
C-5, and Special Operations Forces aircraft.
given workload. This prevents the outsourcing of a majority
of DOD’s maintenance depot workload, thus helping to
Navy
ensure facilities, equipment, and personnel receive a
Naval Sea Systems Command (NAVSEA), headquartered
sufficient peacetime workload to remain qualified and
at the Washington Navy Yard in the District of Columbia,
available in times of emergency.
operates the shipyards and has technical authority for ship
The Six Percent Rule
maintenance operations. The four shipyards within
Title 10 U.S.C. §2476 stipulates investment in the “capital
NAVSEA perform depot-level repairs on ships and
budgets of the covered depots of that military department a
submarines as assigned.
total amount equal to not less than six percent of the
Norfolk Naval Shipyard, VA.
average ... workload at all the depots of that military
department for the preceding three fiscal years.” This
Pearl Harbor Naval Shipyard, HI.
statute is often referred to as the 6 percent rule, and it
Portsmouth Naval Shipyard, ME.
applies to only those named sites in the statute. For those
Puget Sound Naval Shipyard, WA.
sites, the law ensures that departments invest in the
modernization “of depot facilities, equipment, work
For naval aviation, Naval Air Systems Command
environment, or processes in direct support of depot
(NAVAIR), headquartered in Patuxent River, MD, provides
operations.” Investment in the capital budget of a covered
full life-cycle support of naval aviation aircraft, weapons,
depot “does not include funds spent for sustainment of
and systems. It is responsible for the operation of three
existing facilities, infrastructure, or equipment.”
aviation Fleet Readiness Centers (FRCs) providing support
to both Navy and Marine Corps assets.
Considerations for Congress
Shipyard Modernization. The Navy has attributed
FRC East, NC: Fixed and rotary wing aircraft such as
the V-22, F/A-18, F-35, UH-1N, and H-53 variants.
maintenance delays at its four public shipyards to
insufficient capacity, inefficient facility configurations,
FRC Southeast, FL: Aircraft such as the P-3 and EA-
and aging infrastructure and equipment. However, GAO
6B, as well as multiple aircraft engines.
recently identified “unplanned work and workforce
FRC Southwest, CA: Fixed and rotary wing aircraft
factors” as additional causes of delays (GAO-20-588).
such as the AV-8B, E-2, H-60, AH-1, and UH-1 variants.
Congress may wish to delve more deeply into the
Navy’s shipyard modernization efforts, such as the 20-
Marine Corps
year Shipyard Infrastructure Optimization Program
Marine Corps Logistics Command (MARCORLOGCOM),
(SIOP), to ascertain a clearer understanding of the
headquartered in Albany, GA, directs the Marine Depot
Navy’s maintenance situations.
Maintenance Command (MDMC) in repairing, rebuilding,
and modifying all ground combat equipment, and combat
Tyler F. Hacker, Analyst in Defense Logistics
support and combat service support equipment. MDMC
G. James Herrera, Analyst in U.S. Defense Readiness and
Infrastructure
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Defense Primer: Department of Defense Maintenance Depots
IF11466
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