There are three levels at which maintenance is performed on aircraft that
the United States Navy has in inventory at any given time: organizational,
intermediate and depot. Each performs a specific function or serves a
purpose such that anything required for the aircraft to be maintained in a
fully operational status 365 days a year is immediately attended to with the
utmost regard to quality and safety. Some repairs being either too time
consuming or requiring expertise outside of the level is one of the primary
reasons why maintenance is broken down into this three-part system.
Organizational
Maintenance of this type is defined by the efforts necessary required by a
specific unit on a day-to-day basis to keep an airframe in an operational
condition. In addition to the requirement of maintaining assigned aircraft
and aeronautical equipment in a full mission capable status, O-level is also
responsible for the continual improvement of the local maintenance
process.
Intermediate
Maintenance required in support of operational activities. This includes
the repair of specific parts unable to be refurbished at the organizational
level and detailed maintenance of electronic components requiring specific
equipment not peculiar to O-level. I-level is also responsible for
maintaining a constant flow of necessary materials to operational assets
with the lowest possible cost expenditure in order to maximize
efficiency.
Depot
Occasionally in depth maintenance or complex repairs on an airframe are
required to maintain equipment in an operational status. Depot level
repairs would include major alterations or refurbishing of an asset due to
age or upgrade far beyond the capabilities of the organizational level
requiring industrial facilities not available elsewhere. Special Depot
Level Maintenance (SDLM,) commonly perform overhaul operations on airframes
in need of such attention.