soaked with this solution should be used to apply
spillage. The cord construction and lacquer
the preservative. Fuel cells that are returned to
coating must be cautiously safeguarded.
storage until repairs can be accomplished should
have a coating of oil, MIL-L-6082, Grade 1065,
To avoid any undue damage to the cell during
applied to the interior of the cell. The heavier type
handling, follow the following instructions:
of oil will act as a preservative during the sustained
1. Always transport the cell by a well-padded
period. Although complete coverage of the cell
interior is necessary, the preservative oil should
truck or dolly, or by hand carrying.
not be allowed to puddle in the bottom of the cell.
2. Never use any of the cell fittings for hand-
holds while carrying the cell.
When uncrating a fuel cell, you must always
3. Never allow the cell to be dragged or
follow the opening instructions on the crate
rolled on the deck.
or shipping container. These instructions are
4. Before placing the cell on the deck, you
provided for your use to prevent possible damage
should spread an appropriate barrier material on
to the cell and to preserve the crate/shipping
the area where the cell will be placed.
container for future use. Before removing the cell
5. Never place the cell on a bench, pallet, or
from the container, you should be sure that a
table where parts of the cell are allowed to
clean, smooth surface, larger than the cell
overhang.
itself, has been cleared and protected with an
6. If the cell was removed during cold
appropriate barrier material before unfolding the
weather, you should warm the cell to at least 60F
cell. Fuel cells that have been stored for a long
(16C) before collapsing or folding.
time can shrink or become distorted. Cells in this
7. Never use unnecessary force or pressure
condition will be difficult for you to install, and
to compress a collapsed cell into a small package.
they often cause misalignment of the cell fittings
The undue pressure will produce sharp folds that
with the aircraft fittings. To restore a shrunken
cause damage to the cell.
or distorted fuel cell to its original condition, you
8. Never allow the cell to be folded across
should soak the cell in water. The length of time
or beside any of the cell fittings.
required for soaking will normally depend on the
9. Never leave a self-sealing cell in a col-
condition of the cell. Normally, 72 hours is
lapsed condition for a period longer than 1 hour.
enough, as long as the water temperature remains
Bladder-type fuel cells may be left collapsed for
at least 70F (21C). Soaking time can be reduced
a longer period of time, providing the cell is not
by placing the cell in an air-circulating oven at
walked on, severely creased, or abused.
a maximum temperature of 120F (49C) for
10. Always install protective caps on the cell
about 4 hours. It must also be maintained at high
hanger receptacles while the cell is removed from
humidity.
the aircraft.
NOTE: Bladder-type fuel cells and nylon
When a fuel cell remains empty for more than
Pliocels are much more delicate than self-
72 hours, a thin coat of oil, MIL-L-6081, Grade
sealing cells and require extremely careful
1010, should be applied to the inner liner. This
handling. However, the handling precau-
process should be accomplished when the cell is
tions are the same as for self-sealing cells.
installed, or when it is removed from the aircraft
for storage. The oil will act as a temporary
plasticizer, and it will prevent the inner liner from
Installation
drying out and cracking. To get a uniform coat
on the entire inner lining, you should use an oil-
The steps outlined below are generally fol-
soaked cheesecloth to apply the preservative oil.
lowed when installing a fuel cell in an aircraft.
Inaccessibility is a problem with some fuel cells
Check the cell to make certain that it is the
and the only way to properly protect the cell is
proper one for the cavity. Tape all cell openings.
to apply the preservative by spraying. Pliocel-type
Inspect the fuel cell cavity for cleanliness and loose
bladder cells do not require internal preservation
bolts, nuts, etc.; and make certain there are no
except when they are folded and stored for a
sharp metal or protruding edges that may damage
period in excess of 2 weeks. If it becomes
the cell during or after the installation of the fuel
necessary to preserve this particular type of cell,
cell. Tape or otherwise protect the edges of the
the inner. lining must be coated with equal parts
fuel cell if necessary.
of glycerin, MIL-G-491, and water. A cheesecloth
4-36
