Section I. INTRODUCTION
Only as Necessary" (IROAN). Maximum utilization of
diagnostic and test equipment is combined with
This section contains explanations of all
minimum disassembly of the item during the overhaul
maintenance and repair functions authorized for the
various echelons. Section II contains the maintenance
3. Explanation of Columns
a. Functional Group. The functional group is a
Maintenance is any action taken to keep materiel in
numerical group set up on a functional basis. The
a serviceable condition or to restore it to serviceability
applicable functional grouping indexes (obtained from
when it is unserviceable. Maintenance of materiel
the Mobility Command Functional Grouping Indexes)
includes the following:
are listed on the maintenance allocation chart in the
a. Service. To clean, preserve, and replenish fuel
appropriate numerical sequence.
normally are set up in accordance with their function and
proximity to each other.
b. Adjust. To regulate periodically to prevent
b. Components and Related Operation.
column contains the functional grouping index heading,
c. Inspect. To verify serviceability and detect
subgroup headings, and a brief description of the part
incipient electrical or mechanical failure by scrutiny.
starting with the noun name. It also designates the
To verify serviceability and detect
operations to be performed such as service, adjust,
incipient electrical or mechanical failure by use of
inspect, test, replace, repair, and overhaul.
special equipment such as gages, meters, and the like.
c. Echelons of Maintenance. This column contains
e. Replace. To substitute serviceable assemblies,
the various echelons of maintenance by number
designation. An X placed in the appropriate echelon
column and in line with an indicated maintenance
f. Repair. To restore an item to serviceable
function authorizes that echelon to perform the function.
condition through correction of a specific failure or
The X indicates the lowest echelon responsible for
unserviceable condition. This function includes, but is
performing the function, but does not necessarily
not limited to, inspecting, cleaning, preserving,
indicate repair parts stockage at that level. Higher
adjusting, replacing, welding, riveting, and straightening.
echelons are authorized to perform the indicated
g. Align. To adjust two or more components of an
functions of lower echelons.
electrical system so that their functions are properly
This column lists specific
maintenance functions, special tools, cross-references,
h. Calibrate. To determine, check, or rectify the
instructions, and the like pertinent to the operation being
graduation of an instrument, weapon or weapons
system, or components of a weapons system.
i. Overhaul. To restore an item to completely
serviceable condition as prescribed by serviceability
standards developed. This is accomplished through
employment of the techniques of "Inspect and Repair