Chapter 9ENGINEERING CASUALTY CONTROL
otherwise the casualty may be mishandled, and
irreparable damage and possible loss of the ship
may result. War experience has shown that the
cross-connecting of an intact system with a
partly damaged one should be delayed until it is
certain that such action will not jeopardize the in-
tact system. Speed in the handling of casualties
can be achieved only by a thorough knowledge
of the equipment and associated systems, and by
thorough and repeated training in the routine re-
quired to handle specific predictable casualties.
auxiliaries. Each engineering plant operates its
own propeller shaft. If one engineering plant were
to be put out of action by an explosion, shellfire,
or flooding, the other plant could continue to
drive the ship ahead, though at somewhat re-
duced speed.
PHASES OF CASUALTY CONTROL
The handling of any casualty can usually be
divided into three phases: (1) limitation of the ef-
fects of the damage, (2) emergency restoration,
and (3) complete repair.
The first phase is concerned with the im-
mediate control of the casualty so as to prevent
further damage to the unit affected and to pre-
vent the casualty from spreading.
The second phase consists of restoring, as far
as practicable, the services which were interrupted
as a result of the casualty. For many casualties,
the completion of this phase eliminates all other
operational handicaps, except for the temporary
loss of the standby units-which lessens the ships
ability to withstand additional failures. If no
damage to machinery occurred, this phase usually
completes this phase of casualty control.
The third phase of casualty control consists
of making repairs which completely restore an in-
stallation to its original condition.
Split-plant operation is not an absolute in-
surance against damage that might immobilize the
entire engineering plant, but it does reduce the
chances of such a casualty and it prevents damage
to one plant from being transmitted to, or seri-
ously affect the operation of, the other plant or
plants. Split-plant operation is the first step in the
PREVENTION of major engineering casualties.
The fuel oil system is generally so arranged
that by means of fuel oil transfer pumps, suction
can be taken from any fuel oil tank on the ship
and the oil pumped to any other fuel oil tank.
Fuel oil service pumps are used to supply oil from
the service tanks to the main engines. In split-plant
operations the forward fuel oil service pumps of
a ship are lined up with the forward service tanks,
and the after service pumps are lined up with the
after service tanks. The cross-connection valves
in the fuel oil transfer line are always closed ex-
cept when oil is being transferred.
Although geared diesel propulsion plants are
designed for split-plant operation only, some of
the auxiliary and main systems maybe run cross-
connected or split. Among these are the starting
air systems, the cooling water systems, the fire-
main systems, and, in some plants, the fuel and
lube oil systems.
SPLIT-PLANT OPERATION
In diesel-electric installations the diesel
elements are designed for split operation, but
generator elements can be run either split or cross-
connected.
In ships having two or more shafts, a fun-
damental principle of engineering casualty con-
trol is SPLIT-PLANT operation. The purpose of
the split-plant design is to minimize damage that
might result from any one hit.
LOCKING MAIN SHAFT
Most naval ships built primarily as warships
have at least two engineering plants. The larger
combatant ships have four individual engineer-
ing plants.
Split-plant operation means separating the
engines, pumps, and other machinery so that two
or more engineering plants are available, each
complete in itself. Each main engine installation
is equipped with its own piping systems and other
An engineering casualty may affect the rota-
tion of the main shaft and cause further damage.
In such cases, the main shaft should be locked
until necessary repairs can be made, since, except
at very low speeds, movement of the ship through
the water will cause the shaft to turn, whether the
ship is proceeding by its own power or being
towed.
There are no standard procedures for locking
a main shaft which are applicable to all types of
diesel-driven ships. On ships that have main
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