TM 55-1520-240-23-8
10-1
FUEL SYSTEM
(Continued)
10-1
PRESSURE REFUELING
When the REFUEL STATION switch on the overhead
panel is turned on, the refuel control panel in the right
forward intertank bay receives 28 vdc from the switched
battery bus. Turning on the PWR switch at the refuel
panel causes the following to occur:
At the refuel panel, the PWR light comes on and the
LIGHT switch is armed.
Twenty-eight volts is supplied to the inverter, which
then supplies 115 vac to the fuel quantity circuits.
Voltage is supplied to the fuel quantity switch box to
connect signals to the refuel panel selector switch.
All high level shutoff valve test switches are armed.
The gate valve in each of the aft auxiliary fuel tanks
opens.
On aircraft with 82 installed, voltage is supplied to
the ERFS II control panel located on one of the
internal tanks.
NO BREAK - WORK HARDER
As fuel is added through the receptacle at the refuel
station, the pressure refueling valve in each of the
selected tanks is opened by fuel pressure. Fuel passes
through a port in the valve into the tank.
NO BREAK - WORK HARDER
As the fuel level within each tank rises, it lifts the floats
of a shutoff valve in the tank. When the tank is full,
increased pressure in the sensing lines between the
shutoff valve and the refueling valve closes the refueling
valve, shutting off fuel flow to that tank.
NO BREAK - WORK HARDER
During refueling, the shutoff valves in any of the six
tanks can be checked for proper operation by energizing
one of the two (primary or secondary) solenoids on each
valve by a switch on the refuel panel. Energizing the
solenoid raises the float and closes the sensing line to
the refuel valve. This shuts off fuel flow.
NO BREAK - WORK HARDER
If desired, all shutoff valves can be checked at once
by operating the ALL TEST switch on the refuel panel.
This total system check is part of the normal refueling
procedure.
NO BREAK - WORK HARDER
On aircraft with 82 installed, the ERFS II REFUEL
VALVE switch will need to be set to OPEN for fuel to
fill the internal tanks.
10-20
