and adjust any discrepancy in the accuracy of the instrument or test equipment being compared with the certified
g. Install. To set up for use in an operational environment such as an emplacement, site or vehicle.
h. Replace. To replace unserviceable items with serviceable assemblies, subassemblies or parts.
i. Repair. To restore an item to serviceable condition through correction of a specific failure or unserviceable
condition. This includes, but is not limited to, inspection, cleaning, preserving, adjusting, replacing, welding, riveting, and
j. Overhaul. To restore an item to a completely serviceable condition as prescribed by maintenance serviceability
standards prepared and published for the specific item to be overhauled.
k. Rebuild. To restore an item to a standard as nearly as possible to the original or new condition in appearance,
performance, and life expectancy. This is accomplished through the maintenance technique of complete disassembly of
the item, inspection of all parts or components, repair or replacement of worn or unserviceable elements (items) using
original manufacturing tolerances and specifications, and subsequent reassembly of the item.
B-4. Functional Groups . Standard functional groupings are not considered feasible for aviation ground support
equipment due to variation and complexity. Therefore, variations to functional groupings may occur.
B-5. Maintenance Categories and Work Times. The maintenance categories (levels) AVUM, AVIM, and DEPOT are
listed on the Maintenance Allocation Chart with individual columns that indicate the work times for maintenance functions
at each maintenance level. Work time presentations such as 0.1 indicate the average time it requires a maintenance
level to perform a specified maintenance function. If a work time has not been established, the columnar presentation
shall indicate "---". Maintenance levels higher than the level of maintenance indicated are authorized to perform the