Due to the difference in the types of valves,
pumps, filters, and other equipment installed on vari-
ous ships, this section will use general descriptions.
While your ship may have a gate valve in a specific
location, another ship may use a buttefly or limitor-
que valve in the same location. Therefore, we will use
the terms cutout valve, discharge valve, filter, etc.
Specific components will be discussed in the next
FILLING AND TRANSFER SYSTEM
The filling and transfer system (fig. 4-1), and its
interconnecting piping and valves, serves many func-
tions in the operation of the JP-5 fueling system. It is
used primarily for receiving JP-5 aboard to fill the
storage tanks; transferring JP-5 from storage to ser-
vice tanks; transferring JP-5 internally from forward
to aft or port to starboard (or vice versa); and filling
the amidship emergency tanks (on ships so equipped)
when JP-5 is required for boiler fuel. It is also used to
receive and direct JP-5 from the independent defuel
main to a preselected storage tank, and to receive JP-5
from the stripping pump discharge header and direct
it to any storage tank for consolidation. Off-loading of
JP-5 is accomplished by the service pumps through
cross-connection piping to the filling and transfer sys-
The filling system includes all piping, valves, and
related equipment from the filling connections on the
main deck to the fill and suction tailpipe in the storage
The main-deck filling connections provide a
means of attaching the refueling hose to the ship and
controlling the quality and quantity of JP-5 being
received. They are located on the starboard side of the
main deck, outboard of the hangar deck, on fueling
sponsons, or in elevator ramp recesses. The number of
filling connections varies, depending on the type and
class carrier. Most carriers have additional filling con-
nections on the port side to enable refueling from a
barge when moored to a pier.
The probe fueling rig is the standard fitting used
at the starboard-side filling connections for underway
replenish merits. It consists of a fueling probe and a
probe receiver. The receiver is supported by a swivel
fitting mounted on the receiving ship. A 7-inch-di-
ameter, wire-reinforced rubber hose connects the re-
ceiver to the filling connection.
The port-side filling connections use flanges to bolt
the refueling hose to the connection.
Filling connections begin with a 90° elbow and a
stop valve. A flushing line is installed outboard of the
fill connection stop valve on some carrier and am-
phibious aviation-type ships. It is used for hose flush-
ing and to receive the initial flow during refueling.
The flushing line directs fuel flow to the reclamation
system and into contaminated storage tanks through
the defueling main. All filling connections should be
equipped with the following:
1. A sampling connection, to determine the quality
of fuel being received.
2. A pressure gage, to determine the discharge
pressure from the refueling source.
3. A low-pressure air connection, for blowing JP-5
in the hose back to the refueling source (if necessary).
The downcomer is that section of piping that con-
nects the filling connection on the main deck with the
transfer main on the seventh deck. There is normally
one downcomer for each filling connection installed.
The transfer main runs fore and aft through the bilge
just below the seventh deck. New CV/CVNs have a dual
transfer main that runs forward and aft on both the port
and starboard sides, creating a closed loop transfer
main. The transfer main interconnects the forward and
aft group of storage tanks, and the amidship emergency
tanks (on ships so equipped). In addition to being con-
nected to the downcomers, it is also connected to the
independent defuel main and the discharge headers of
the transfer and stripping pumps.
Cutout valves are installed at strategic points
throughout the transfer main, mostly at fore and aft
bulkheads. These valves are used to isolate the system
during the secured condition and to control the flow of
JP-5 during various transfer and filling operations. Each
valve is unclassfifed or Damage Control marked @-ray.
The extreme forward and aft ends of the transfer
main are connected to the transfer-main branch headers.
The transfer-main branch headers extend outboard from
the transfer main and interconnect the storage tank
manifolds with the transfer main. Normally there are
only two branch headers for each of the forward and aft
groups of tanks: one port and one starboard. But on
ships with double bottom and peak tanks for JP-5 stor-
age. additional branches are required.
Located between the transfer-main branch head-
ers and the storage tank fill and suction tailpipes are
valve manifolds. All manifold valves are Damage
Control marked @-ray and MUST be closed when not
actually in use.