the materials commonly used for these purposes are
Learning Objective: Recall factors that affect
Plugging and Patching Materials
underwater repairs and the procedures used for
Plugging and patching materials include wooden
plugging and patching holes in the hull of a ship.
plugs and wedges, wooden shoring, prefabricated
Any rupture, break, or hole in the ship's outer hull
wooden box patches in various sizes, rags, pillows,
plating, particularly below the waterline, can allow
mattresses, blankets, kapok life jackets, metal plate,
seawater to enter the ship. If flooding continues
folding metal plate patches, flexible sheet metal
uncontrolled, the ship will sink.
patches, prefabricated steel box patches, bucket
patches, and welded steel patches.
When the underwater hull is pierced, there are only
two possible courses of action. They are as follows:
Plug the holes or openings.
Securing materials include assorted hook bolts,
manila line, wire rope, chain, machine bolts, angle
clips for welding, and shoring. Backup materials
within the ship to prevent further progress of
include mess tables, metal joiner doors, buckets,
plywood or lumber, sheet metal, and metal plate.
Dewatering can be effective only after these two
measures have been taken.
The one very important thing to remember about
Gasket materials include sheet and strip rubber,
flooding is that a ship can sink just as easily from a
leather, canvas, rags, and oakum.
series of small and insignificant looking holes, as it can
from one large and more dramatic looking hole. The
natural tendency is to attack the obvious damage first
and to overlook the smaller holes in the hull and in
interior bulkheads. You may waste hours trying to
What document provides several repair locker
patch large holes in already flooded compartments.
inventory lists for various types of ships?
Meanwhile, you disregard the smaller holes through
Table of Allowance List (TOAL)
which progressive flooding is taking place. In many
Allowance Equipage List (AEL)
cases, it would be better to concentrate on the smaller
holes. As a rule, the really large holes in the underwater
Damage Control Equipment List (DCEL)
hull cannot be repaired until the ship is dry-docked.
Master Repair Locker List (MRLL)
All holes in the hull, large or small, should be
On a Navy ship, what personnel are
plugged completely as soon as possible. As an interim
responsible for damage control?
measure, all holes should be partially plugged if they
cannot be completely plugged. Even a partial plug can
substantially reduce danger of sinking by dramatically
Damage control parties only
reducing the amount of water entering the ship.
Damage control supervisors only
Holes in the hull that are at or just above the
waterline should be given immediate attention. Holes
Damage control assistants and damage
in this location may not appear to be dangerous but they
control team leaders only
are. As the ship rolls or loses buoyancy, the holes
After each use, all damage control kits and
become submerged and allow water to enter at a level
repair locker equipment must be inventoried
that is dangerously high above the ship's center of
to meet what requirements?
gravity. These holes must be plugged at once. Give the
holes at the waterline or on the low side priority (if the
ship is listing), and then plug the higher holes.
The same methods and materials used to repair
holes above the waterline are also used, for the most
part, in the repair of underwater holes. The repair of