delivery ship by opening the compressed air valve to the
fueling connection, or (2) have the supplying ship take
a back suction, which also requires that the air valve be
opened. As soon as the fuel hose has been cleared,
IMMEDIATELY uncouple the hose and return it to the
You also must be familiar with the procedures used
to discharge fuel. The following list shows some of the
steps typically used to discharge fuel oil:
1. Be sure the tanks from which fuel is to be
discharged are filled and topped off to the 95 percent
2. If necessary, heat the oil to the temperature
required to produce a viscosity of 450 SSU. This
procedure is not usually required with distillate fuel.
3. Sound all tanks that will be used.
4. Couple the fuel hose and rig it according to
5. Line up the fuel oil system to discharge fuel,
and test the operation of the fuel oil pumps.
6. Place red flags over the side of the ship at the
7. Be sure the officer of the deck has draft
readings taken forward and aft before and after fueling.
8. Set the fueling detail, setup the fueling board,
and fill in available data on the fueling sheet for the
9. Man fueling stations about one-half hour
before the expected time of approach of the ship to be
fueled. Be sure personnel at the fueling stations test
sound-powered phone circuits, connect air hoses to the
fueling connections, screw in thermometers and
pressure gauges, warm up the fuel pumps, and open
valves to the fuel tanks. When the fueling detail is ready
and has made all required checks and preparations,
report to the fueling officer. The fueling officer will
inform the bridge and request that the smoking lamp be
10. When you get word to start discharging fuel,
start the pumps and operate them slowly at first, then
bring them up to full-rated capacity. Bui!d up a pressure
of approximately 40 psi at the fueling connections.
11. Continue pumping at the rated pump capacity
until a tank is down to approximately 35 percent of its
capacity; then shift pump suction to another tank. Slow
the pumps and stop them upon a request from the
12. Remove fuel oil from the fuel hose by blowing
air through it, or the delivery ship may take a back
suction. Disconnect the hose and rig and handle them
according to prescribed procedures.
13. Sound the tanks and compute the amount of
Whenever a liquid is shifted from one place to
another aboard ship, there is an effect on the ships list,
trim, or stability. One of your routine jobs is to reduce
any instability. To do that, you should keep as many fuel
oil tanks as possible filled with fuel oil to the 95 percent
level. There may be other times when you may have to
use the ballasting system to move seawater to or from
empty tanks. Normally, you will need to do that only in
case of damage or when the ship has an unusually small
store of fuel oil that brings on instability.
To keep the fuel oil tanks at 95 percent capacity, you
should accumulate leftover fuel oil from partly used
tanks so only those tanks actually in use are less than 95
percent full. This prevents free surface effect that occurs
when a liquid only partly fills a tank and moves freely
back and forth as the ship moves. There is some free
surface effect when a tank is filled to the 95 percent
level, but the effect is limited because the overhead
interferes with the free movement of the liquid beyond
a certain point. There is more danger of serious loss of
stability from tanks that are half-full than from tanks
that are 95 percent full.
The ballasting system allows controlled flooding of
certain designated tanks to control the ships stability.
You can use the ballasting system to flood all tanks that
are designated as fuel oil and ballast tanks and to flood
certain voids. The ballasting and deballasting systems
are arranged so all designated compartments and tanks
can be ballasted either separately or together and
drained either separately or together. Seawater is used
as ballast, and it may be taken from the firemain or
directly from sea chests. Use drainage pumps or
eductors to remove the ballast water. Handle all
ballasting and deballasting according to the sequence
tables furnished for each ship or class of ship.
Ballasting empty fuel oil tanks helps control
stability by maintaining a low center of gravity in the
ship and by keeping off-center tanks full to prevent
off-center flooding. Ballasting also contributes to
nonflammable liquid at the shell of the ship to absorb
fragments and otherwise minimize torpedo damage.