TM 5-5420-280-23&P
SUPPORTING INFORMATION
RAPIDLY EMPLACED BRIDGE (REB)
NSN 5420-01-481-3959 P/N 12480471
MAINTENANCE ALLOCATION CHART (MAC) INTRODUCTION
THE ARMY MAINTENANCE SYSTEM (AMS)
This introduction provides a general explanation of all maintenance and repair functions authorized at
the two maintenance levels under the Two-Level Maintenance System concept.
The Maintenance Allocation Chart (MAC) (WP 0130 00) designates overall authority and responsibility
for the performance of maintenance functions on the identified end item or component. The application of
the maintenance functions to the end item or component shall be consistent with the capacities and
capabilities of the designated maintenance levels, which are shown on the MAC in column (4) as:
Field Level (Tactical)-C (operator/crew), O (unit) maintenance, and F (Direct Support).
Field Maintenance is on-system maintenance and is mainly replacement of defective parts and
preventative maintenance. Field maintenance returns repaired equipment to operation. It covers
crew, unit, and selected DS maintenance tasks. Some "off-system" maintenance can be done at
field level if, based on task analysis, it is simple to complete or it is critical to mission readiness.
Sustainment Level (Sustainment)-H (General Support) and D (Depot).
Sustainment is off-system maintenance and is mainly repair of defective or worn out
equipment/parts. Sustainment maintenance returns repaired equipment/parts to the supply
system. It covers selected DS tasks, GS, and Depot maintenance.
The tools and test equipment requirements (immediately following the MAC) list the tools and test
equipment (both special tools and common tool sets) required for each maintenance function as referenced
from the MAC.
The remarks (immediately following the tools and test equipment requirements) contain supplemental
instructions and explanatory notes for a particular maintenance function.
MAINTENANCE FUNCTIONS
Maintenance functions are limited to and defined as follows:
1. 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).
This includes scheduled inspection and gagings and evaluation of cannon tubes.
2. Test. To verify serviceability by measuring the mechanical, pneumatic, hydraulic, or electrical
characteristics of an item and comparing those characteristics with prescribed standards on a scheduled
basis, i.e., load testing of lift devices and hydrostatic testing of pressure hoses.
3. 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. This includes scheduled exercising and purging of recoil mechanisms.
4. Adjust. To maintain or regulate, within prescribed limits, by bringing into proper position, or by
setting the operating characteristics to specified parameters.
5. Align. To adjust specified variable elements of an item to bring about optimum or desired
performance.
