Figure 3.8. Engine Disassembly Stand.
and time available. Maintenance that cannot be performed at the
assigned level may be reassigned to the next higher level.
Generally, there is no deviation from the assigned level of
maintenance. However, in cases of operational necessity, higher
level function is assigned to a lower level by the maintenance
officer of the level to which the function is originally assigned.
Figure 3.10 shows an example of a maintenance allocation chart for
UH1D and H series helicopters. The symbols "O, F, H and D"
represent: organizational maintenance (O), direct support maintenance
(F), general support maintenance (H), and depot maintenance (D).
When one of these symbols is placed on the allocation chart, it
indicates the lowest level of maintenance responsible for performing
the particular maintenance function. Maintenance levels higher than
the level symbolized on the chart are authorized to perform the
The terms used in block (3) of the maintenance allocation
chart are explained in table HI for convenience in reviewing and for
STORAGE AND PRESERVATION
The degree of preservation is determined by the anticipated
length of time an engine is expected to be inactive. The three
categories of storage are: