TM 10-6640-239-13 B-1 APPENDIX B MAINTENANCE ALLOCATION CHART (MAC) Section I.  INTRODUCTION B-1. GENERAL. a. This section provides a general explanation of all maintenance and repair functions authorized at various maintenance categories. b. The Maintenance Allocation Chart (MAC) in Section II designates overall authority and responsibility for performance of maintenance functions on the identified end item or component.  The application of the maintenance functions to the end item or component will be consistent with the capacities and capabilities of the designated maintenance categories. c. Section III lists the tools and test equipment (both special tools and common tool sets) required for each maintenance function as referenced from Section II. d. Section IV contains supplemental instructions and explanatory notes for a particular maintenance function. B-2. MAINTENANCE FUNCTIONS. Maintenance functions will be limited to and are defined as follows: a. Inspect.  To determine the serviceability of an item by comparing its physical, mechanical, and/or electrical characteristics 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 the optimum performance. f. Calibrate.  To determine and cause corrections to be made or to be adjusted on instruments or test, measuring, and diagnostic equipment 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 3rd position code of the SMR code. i. Repair.  The application of maintenance services, including fault location/troubleshooting, removal/installation,