TM 1-1520-240-BD
GLOSSARY
SECTION I. TERMS AND DEFINITIONS
This appendix contains terms and definitions used in the task of airframe battle-damage assessment and repair.
Airframe Section - A major part of the airframe such as
the cockpit, cabin or tailcone.
Airframe Zone - An area or section of the airframe
defined for the purpose of assessing battle damage.
Area Loss - The fractional planform area of a structural
member removed by ballistic damage.
Assessment Rule - A specific criterion used to assess a
particular damage condition.
Assessor - A trained maintenance technician whose
function it is to assess aircraft battle damage.
Axial - Pertaining to the line about which a rotating body
turns.
Axial Load - Force or stress along the line about which a
rotating body turns.
Battle -Damaged Assessment - The process used to
determine if repair of a battle-damaged aircraft or
system can be safely deferred either for a one-time
evacuation flight of the aircraft or to return the aircraft to
service for a limited number of flight-hours. The three
major tasks of battle-damage assessment are damage
inspection, damage evaluation, and repair deferability
assessment.
Bay Group - Two or more adjacent bays in either
direction.
Cap - Flat Strip attached along top or bottom edge of
spar, or around rib.
Category I Structure - Primary framing members such
as frames, beams, bulkheads and longerons.
Category II Structure - Primary skins and stringers.
Category III Structure - Fixed secondary structures such
as formers, intercostals, and channels.
Category
IV
Structure
-
Removable
secondary
structures such as fairings, cowlings, doors and panels.
Channels - Structural member of channel form (eg top
hat, or U).
Compression - The act of pressing together.
Cowlings
-
A
streamlined
housing
for
aircraft
components.
Damage,
Battle
-
Damage
caused
by
ballistic
projectiles, explosions, and fire.
Damage, Primary - Damage caused directly by the
ballistic projectiles, explosions, or fire associated with an
attack.
Damage, Secondary - Damage to structural members
not directly exposed to the attack caused by flying the
aircraft with battle-damaged members failed or missing.
Damage Cleanup - The process of removing and/or
smoothing damaged material.
Damage Diagram - A sketch of a portion of the airframe
used to define the location of damaged members.
Damage Evaluation - The process used to determine
whether a damaged structure is serviceable or failed.
Damage Inspection - The process of inspecting for the
purpose
of
locating,
identifying,
classifying,
and
recording battle damage.
Damage Labels - Marks and symbols placed on a
structural member to identify areas of damage.
Damage Limit - The amount of damage to a member
which, if exceeded, requires the member to be classified
as failed.
Damage Measurement - The process of determining the
dimensions of damage to a structure.
Damage Mode - A type of damage such as a crack, hole
or spall.
Damage Monitoring - Periodic inspections of unrepaired
damage to check for deterioration and damage growth.
Damage Report - A form for recording damage by type,
location and nature of damage. Damage measurements
and failure criteria are also recorded.
Glossary-1
