-2 chapter 8

Question 1

OPERATIONAL PRESERVATION

Answer 1

The day to day
application of CPCs to prevent corrosion on operational
aircraft is known as operational preservation

Question 2

NON-OPERATIONAL PRESERVATION

Answer 2

Preservation of aircraft or components during periods
of prolonged inactivity, storage, or shipment is known
as non-operational preservation

Question 3

TYPES OF CPCS

Answer 3

water displacing and non‑water

displacing compounds.

Question 4

WATER DISPLACING COMPOUNDS

Answer 4

Water
displacing CPCs can be used to remove water, sea
water, or other electrolytes from metal surfaces

Question 5

NON-WATER DISPLACING COMPOUNDS

Answer 5

Non‑water displacing CPCs may be used on dried
surfaces or on surfaces which have been first treated
with a water displacing CPC

Question 6

TIME LIMITATIONS OF CPCS

Answer 6

Because of their
temporary nature, CPCs must be regularly removed
and replaced to provide continuing corrosion protection.

Question 7

MIL-PRF-81309 (CORROSION PREVENTIVE
COMPOUND, WATER DISPLACING, ULTRA THIN
FILM)

Answer 7

general purpose corrosion
preventive compound which can be used whenever a
CPC or a water displacing compound is called for but
no specification is referenced

Question 8

MIL‑PRF‑81309 types:

Answer 8

• Type I products are designed to both
  inhibit mildew growth and prevent corrosion
  -Type II is a soft, thin film product for
  general use, particularly on moving or sliding parts
  where some lubrication is needed, such as hinges or
  bomb racks.
  -Type III . An ultra thin, soft film primarily for use
  on avionics and electronic equipment

Question 9

MIL-DTL-85054 (CORROSION PREVENTIVE
COMPOUND, WATER DISPLACING, TRANSPARENT
(FORMERLY AMLGUARD)

Answer 9

water
displacing CPC which forms a clear, dry, flexible film. It
is intended for use as a protective coating until painting
is practical.

Question 10

MIL-PRF-16173 (CORROSION PREVENTIVE

COMPOUND, SOLVENT CUTBACK)

Answer 10

comes in five different grades of CPCs which can be
applied by brushing, dipping, or spraying. Grades 1, 2,
and 4 do not displace water and shall be applied to dried surfaces or to surfaces which have first been treated with MIL‑PRF‑81309.

Question 11

MIL-PRF-16173 types:

Answer 11

-Grade 1. A thick, hard, black CPC which can
be removed with difficulty using mineral spirits or paint
removers. It offers the most corrosion protection of all
the CPCs indoors and outdoors, and may be used at
temperatures down to 0°F (‑18°C)
-Grade 2. A thick, soft, greaselike, brown CPC
that remains tacky and can be removed with mineral
spirits. It protects under relatively severe conditions and,
given adequate maintenance touch‑up as necessary,
can be used for most maximum protection requirements.
It may be used at temperatures down to ‑40°F (‑40°C).
-Grade 3. A thin, soft film, water‑displacing CPC.
MIL‑PRF‑81309 Type II may be used as a substitute.
As Grade 3 does not have lubricating or penetrating
properties, it shall not be used as a direct substitute for
MIL-PRF-81309 Type II.
-Grade 4. A thin, relatively dry, semitransparent
film through which identification can be read. It may be
used at temperatures down to ‑40°F.

Question 12

MIL-PRF-63460 (LUBRICANT, CLEANER, AND
PRESERVATIVE FOR WEAPONS AND WEAPON
SYSTEMS)

Answer 12

thin, water displacing,
protective, penetrating lubricant used for cleaning,
lubrication, and preservation of aircraft hinges and
small or large caliber weapons.

Question 13

MIL-PRF-32033 (LUBRICATING OIL, GENERAL
PURPOSE, PRESERVATIVE (WATER DISPLACING,
LOW TEMPERATURE)

Answer 13

is a general purpose, water displacing,
lubricating oil with preservative properties, and is
intended for the lubrication and preservation of aircraft
components.

Question 14

MIL-L-87177 (LUBRICANTS, WATER

DISPLACING, SYNTHETIC)

Answer 14

synthetic lubricant with added corrosion inhibitor.
This material creates a non-tacky film on the surface.
MIL-L-87177 does not displace water or penetrate as
thoroughly as MIL‑PRF‑81309 or MIL-PRF-32033 and
should only be used on surfaces that have been wiped
dry

Question 15

APPLICATION OF POLISH AND WAX.

Answer 15

Polishing
and waxing of aircraft exterior surfaces is prohibited
unless authorized by parent service organization
directives.

Question 16

SHORT TERM STORAGE (30 DAYS OR

LESS)

Answer 16

Short term storage shall be defined as any
period up to 30 days for the purposes of this manual.
When assemblies or parts are removed from the aircraft
for repair, or to gain access to areas of the aircraft for
maintenance, they shall be treated to prevent corrosion
prior to placement into short term storage. All items shall
be stored indoors in a covered area to protect them from
the elements

Question 17

In the absence of other requirements,

the following procedures apply(short erm storgage):

Answer 17

a. Clean part or assembly in accordance with
Chapter2.
b. Assemblies or parts having bare metal surfaces,
such as internal and working surfaces on landing gear
components, shall be properly lubricated with the aircraft greases or oils normally applied in service.
c. High strength steel components which are
stripped of their protective coatings shall be protected
using one of the following methods:
-Compound, Corrosion Preventative 4
-Water-Displacing MIL-PRF-81309
(1) Apply a film of CPC (MIL‑PRF‑81309
Type II) to all bare surfaces whenever there is a lapse
of two hours or more in the repair cycle. The part shall
then be loosely overwrapped with barrier material
(MIL-PRF-131Class 1).
(2) Wrap part in VCI film, MIL‑PRF‑22019, or
VCI paper, MIL‑PRF‑3420, and seal with tape, SAE
AMS-T-22085.
d. Completely painted parts need no other special
protective measures, except in marine or high humidity
environments. In these cases, the part shall be loosely
overwrapped with barrier material (MIL‑PRF‑131
Class1).
e. Prior to rework or reapplication of protective
coatings, remove CPC with degreasing solvent
(MIL‑PRF‑680 Type II or III) or non‑aqueous cleaner
(MIL‑PRF‑32295 Type II) as required. Reapply the
appropriate aircraft lubricant to areas requiring
lubrication. CPCs shall not be used for lubrication in
lieu of the lubricant specified for use on a particular part
or assembly.

Question 18

LONG TERM STORAGE (OVER 30 DAYS)

Answer 18

If
the storage of assemblies or parts will exceed 30 days,
increased protective measures are required, particularly
on critical parts and high strength steel components.
All items shall be stored indoors in a covered area to
protect them from the elements.

Question 19

In the absence of other requirements,

the following procedures apply:(long term storage)

Answer 19

a. Clean part or assembly in accordance with
Chapter2.
b. All bare metal surfaces, and surfaces with
damaged plating or paint, shall be protected using one
of the following methods:
Compound, Corrosion Preventative 4
Water-Displacing
MIL-PRF-81309
Compound, Corrosion Preventive 6
MIL-PRF-16173
(1) Apply water displacing CPC (MIL‑PRF‑81309
Type II) followed by long term CPC (MIL-PRF-16173
Grade 4). The part shall then be overwrapped with
barrier material (MIL‑PRF-131 Class 1) and sealed with
tape (SAE AMS-T-22085 Type II).
(2) Wrap part in VCI film, MIL‑PRF‑22019, or
VCI paper, MIL‑PRF‑3420, and seal with tape, SAE
AMS-T-22085.
c. Completely painted parts need no other special
protective measures, except in marine or high humidity
environments. In these cases, the part shall be
overwrapped with barrier paper (MIL-PRF-131 Class 1)
and sealed with tape (SAE AMS-T-22085 Type II)
d. Depending upon the length of time in storage,
reapplication of protection may be required.
(1) Refer to Table 8-1 for time limitation
information on CPCs.
(2) Replace torn or damaged VCI film or paper.
Intact VCI film or paper has a storage limit of one year.
e. Prior to returning the part or assembly to service,
remove CPCs with degreasing solvent (MIL-PRF-680
Type II or III) or non‑aqueous cleaner (MIL‑PRF‑32295
TypeII) as required. Reapply the appropriate aircraft
lubricant to areas requiring lubrication. CPCs shall not
be used for lubrication in lieu of the lubricant specified
for use on a particular part or assembly.