Section I. INTRODUCTION
This appendix provides a summary of the maintenance operations for AB-621/G, AB-621A/G and
MK-2044/G. It authorizes categories of maintenance for specific maintenance functions on repairable items
and components and the tools and equipment required to perform each function. This appendix may be used
as an aid in planning maintenance operations.
B-2. Maintenance Function
Maintenance functions will be limited to and defined as follows:
Inspect. To determine the serviceability of an item by comparing it physical, mechanical, and/or
electrical characteristics with established standards through examination.
b. Test. To verify serviceability and to detect incipient failure by measuring the mechanical or electrical
characteristics of an item and comparing those characteristics with prescribed standards.
Operations required periodically to keep an item in proper operating condition, i.e., to
clean (decontaminate), to preserve, to drain, to paint, or to replenish fuel, lubricants, hydraulic fluids, or
compressed air supplies.
To maintain, within prescribed limits, by bringing into proper or exact position, or by setting
e operating characteristics to the specified parameters.
to adjust specified variable elements of an item to bring about optimum or desired perfor-
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. Install. The act of emplacing, seating, or fixing into position an item, part, module (component or
assembly) in a manner to allow the proper functioning of the equipment or system.
h. R e p l a c e .
The act of substituting a serviceable like type part, subassembly, or module (component or
assembly) for an unserviceable counterpart.
The application of maintenance services (inspect, test, service, adjust, align, calibrate,
replace) or other maintenance actions (welding, grinding, riveting, straightening, facing, remachining, or
resurfacing) to 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.