TM 55-1680-320-23 & P
the maintenance level to which the function is assigned. This transfer of a maintenance function to a lower maintenance
level does not relieve the higher maintenance level of the responsibility for the function. The higher level of maintenance
has the authority to determine; (1) if the lower level is capable of performing the work, (2) if the lower level requires
assistance, technical supervision, and on site inspection, and (3) if the authorization will be granted.
g. Changes to the Maintenance Allocation Chart will be based on continuing evaluation and analysis by responsible
technical personnel and on reports received form field activities.
B-3. Maintenance Functions. Maintenance functions will be limited to and defined as follows:
a. Inspect. To determine the serviceability of an item by comparing its physical, mechanical, and / or electrical
characteristic with established standards through examination (e.g., by sight, sound or feel).
b. Test. To verify serviceability by measuring the mechanical pneumatic, hydraulic or electrical characteristics of an
item and comparing those characteristics with prescribed standards.
c. Service. Operations required periodically to keep an item in proper operating condition, i.e., to clean (includes
decontaminate, when required), to preserve, to drain, to paint, or to replenish fuel, lubricants, chemical fluids, or gases.
d. Adjust. To maintain or regulate, within prescribed limits, by bringing into proper or exact position, or by setting
the operating characteristics to specified parameters,
e. Align. To adjust specified variable elements of an item to bring about optimum or desired performance.
f. Calibrate. To determine and cause corrections to be made or to be adjusted on instruments or test, measuring and
diagnostic equipments used in precision measurement.
Consists of comparisons of two instruments, one of which is a
certified standard of known accuracy, to detect and adjust any discrepancy in the accuracy of the instrument being compared.
g. Remove/Install. To remove and install the same item when required to perform service or other maintenance
functions. Install may be the act of emplacing, seating, or fixing into position a spare, repair part, or module (component
or assembly) in a manner to allow the proper functioning of an equipment or system.
h. Replace. To remove an unserviceable item and install a serviceable counterpart in its place. “Replace” is authorized
by the MAC and is shown as the 3d position code of the SMR code.
i. Repair. The application of maintenance services, including fault location/ troubleshooting removal installation,
and disassembly / assembly3 procedures, and maintenance actions4 to identify troubles and restore serviceability to an item
by correcting specific damage, fault, malfunction or failure in a part, subassembly, module (component or assembly), end
item or system.
NOTES:
1
Services - inspect, test, service, adjust, align, calibrate, and / or replace.
2
Fault locate / troubleshoot - The process of investigating and detecting the cause of equipment malfunctioning
the act of isolating a fault within a system or unit under test (UUT).
3
Disassemble / assemble - encompasses the step-by-step taking apart (or breakdown) of a spare / functional group
coded item to the level of its least componency identified as maintenance significant (i.e., assigned an SMR code)
for the category of maintenance under consideration.
4
Actions - welding, grinding, riveting, straightening, facing, remachining and / or resurfacing.
B-3
