Standardization of scheduled maintenance
procedures is accomplished through the use of the
following PMS publications:
Maintenance requirements cards (MRCSs
Sequence control cards/charts (SCCSs
Periodic maintenance information cards
Standard depot-level maintenance (SDLM)
Revisions to the PMS publications are
published at intervals. These revisions add, delete,
revise, or change requirements, and are based
on factual data accumulated as a result of
maintenance experience with the aircraft. Where
conflict exists between the information contained
in a PMS publication and another maintenance
directive, the PMS publication takes precedence.
The types of PMS publications and their uses are
described in the following paragraphs.
Maintenance Requirements Cards (MRCs)
The prescribed maintenance requirements, as
shown in the PMS publications, are presented to
maintenance personnel in the form of mainte-
nance requirements cards (MRCs). Usually, sets
of cards are provided for each aircraft model
being maintained under the inspection system. For
each type of scheduled inspection, one set
of MRCs is provided. All of the minimum
requirements for the accomplishment of any
particular scheduled maintenance task, or portion
thereof, are contained in a set of these cards.
The maintenance requirements cards are the
working documents for squadron inspections and
preventive maintenance actions. These 5- by
8-inch cards contain the particular system,
subsystem, area, or component using a logical
sequence for accomplishment. MRCs identify the
recommended rating, performance interval, and
the work area involved. Assembled into sets and
numbered in sequence, the cards contain pertinent
information required by each maintenance person
to complete each task.
Data for each task includes the following
information about the task: a description; the time
required to perform the task; the power, tool,
and material requirements; and
information on such items as pressures and torque
values. Also included, when necessary, is a
diagram of the area in which the work is to be
The work plan, or order of performing the
requirements, specified on the MRCs is arranged
in two ways.
1. The preflight, postflight, and daily work
is performed item by item in sequential order
arranged on consecutively numbered cards.
2. The calendar inspection work is controlled
by the order of arrangement of the items on the
MRCs and, in addition, employs a sequence
control chart for scheduling the MRCs. The
calendar MRCs are not necessarily scheduled in
numerical card number sequence.
A master file copy of current MRCs must be
maintained within the maintenance department.
This master file copy reflects all revisions to the
published card sets, plus any locally added
requirements. Local periodic maintenance
requirements, not covered by the published MRC
sets, can be added as outlined in chapter 3 of this
When an aircraft is undergoing an inspection,
one or more of the MRC(s) is/are given to the
maintenance person in the specified order.
Certification of completion of the work is not
made on the cards; therefore, the cards are used
as many times as their condition permits.
Before a set of cards is issued to the check crew
supervisor, each card should be checked against
the master file set to ensure that it is complete and
current. (This is a function of the quality
The front side of each basic card (fig. 4-16)
begins a new maintenance requirement. The back
side of the card carries the same number as the
front with an additional point number. In case
the text and illustrations cannot be contained on
the front and back of the basic card, an additional
point-numbered card is used. For example, the
front of an MRC maybe numbered 21, the back
of this card 21.1, and a continuation card 21.2.
Point-numbered cards are not listed on the
sequence control charts.