INTERIM CHANGEA change having an action
classification of immediate or urgent and issued by
INVENTORY CONTROLThe phase of military
logistics that includes management, cataloging,
requirements determination, procurement, dis-
tribution, overhaul, and disposal of material.
Synonymous with material control, material
management, inventory management, and supply
INVESTIGATIONInquiry into a condition or
situation systematically for the purpose of
developing and providing factual information to
IPBIllustrated Parts BreakdownA manual con-
taining illustrations and part numbers for all parts
of the aircraft or equipment on which it is issued.
The IPB contains information required for ordering
parts, including part numbers, and for identifying
parts and arrangements of parts in assemblies.
IRACInterim Rapid Action Change.
ITEMAny level of hardware assembly; for example,
segment of a system, subsystem, equipment, or
ITEMS PROCESSED (ITEMS/P)This term
identifies the total number of times an AT code is
applied toward a WUC.
JCNJob Control NumberThe JCN is a 9-, 10-, or
11-digit alphanumeric code that identifies each
individual maintenance action.
JOAPJoint Oil Analysis Program.
JULIAN DATEThe year and numerical day of the
year identified by four numeric characters. The
first character indicates the year and the remaining
three characters specify the day of the year; for
example, 9209 indicates the 209th day of 1999 or
28 July 1999.
LAMSLocal Asset Management SystemAn
automated management information system,
provides for standardized local management of
IMRL assets through the use of bar code
technology. It provides for an accurate wall-to-wall
inventory, which can be accomplished by unit
personnel, resulting in significant reductions of
manpower expenditures and operational
LANDINGThe controlled return of an aircraft in
flight to the surface. It includes touch and go
(carrier or field) providing the landing gear touches
the surface. A bolter is an attempted arrested
landing on a carrier in which the landing gear or
hook touches the deck but the arresting gear is not
engaged and the aircraft continues in flight.
LCFLow Cycle FatigueA fatigue cracking failure
mode that is defined by the frequency and
characteristics of a loading that causes a crack.
LCF is caused by stresses built up by mechanical/
thermal cycles which occur only a few times per
flight. The four most significant LCF events are:
stop/start/stop cycles, rapid major changes in
operating temperature, rapid major changes in
rotational speed, and significant increases in
aerodynamic loading of the blades/ disks.
LIFE CYCLESThe total life span of an aeronautical
system beginning with the concept formulation
phase and extending through the operational phase
up to retirement from the inventory.
LIQUID PENETRANTMethods used for the
detection of surface cracks or discontinuities,
where the inspection surfaces are sprayed with or
immersed in liquid. The excess liquid is removed,
and the defect is indicated visually by color or
LOANAircraft loaned to non-Navy organizations
for non-Navy purposes. A lease may or may not be
required to cover the loan.
NOTE: Aircraft that are in the Navy inventory
but not in the physical custody of the Navy are
either on bailment or on loan. Bailment
indicates usage by the bailee for the Navy,
while loan indicates usage by the lessee for the
LOGISTICSThe science of planning and carrying
out the movement and maintenance of forces. For
its most comprehensive sense, those aspects of
military operations that deal with design and
development, acquisition, storage, movement, dis-
tribution, maintenance, evaluation, and disposition
of material; movement, evaluation, and hospital
inspection of personnel; acquisition or construc-
tion, maintenance, operation, and disposition of
facilities; and acquisition or furnishing of services.
LOOK PHASEThe portion of an inspection that
includes the basic requirements outlined by the
PMICs, excluding repair of discrepancies, that
cannot be completed within the time allotted on