TM 1-1520-238-10
2-36
Table 2-1.
Pilot Fuel Control Panel Switch Functions
Switch Position
Result
Indication
ENG 1 set OFF
Energizes fuel crossfeed/shutoff
valve of the No. 1 engine to the
closed position thus shutting off fuel
flow to that engine.
None
ENG 1 set ON
Energizes fuel crossfeed/shutoff
valve of the No. 1 engine to the
position commanded by the
CROSSFEED switch.
None
ENG 2 set OFF
Energizes fuel crossfeed/shutoff
valve of the No. 2 engine to the
closed position, thus shutting off fuel
flow to that engine.
None
ENG 2 set ON
Energizes fuel crossfeed/shutoff
valve of the No. 2 engine to the
position commanded by the
CROSSFEED switch.
None
CROSSFEED set FWD TK
Both engines feed from the forward
fuel cell.
FWD cell fuel quantity indicators
register fuel decrease while AFT cell
indicators remain constant.
CROSSFEED set NORM
ENG No. 1 feeds from the forward
fuel cell; ENG No. 2 feeds from the
aft fuel cell.
Both fuel quantity indicators register
fuel decrease from consumption.
CROSSFEED set AFT TK
Both engines feed from the aft fuel
cell.
AFT cell fuel quantity indicators
register fuel decrease while FWD cell
indicators remain constant.
EXT TK switch set ON
Pressurized air is made available to
all external tanks for transfer of fuel
to the main fuel cells.
Both fuel quantity indicators register
fuel increase during fuel transfer
operation.
TRANS set TO FWD
Fuel is being pumped from AFT cell
to FWD cell by the transfer pump.
AFT cell fuel quantity indicators
register fuel decrease while FWD cell
indicators register fuel increase.
TRANS set TO AFT
Fuel is being pumped from FWD cell
to AFT cell by the transfer pump.
FWD cell fuel quantity indicators
register fuel decrease while AFT cell
indicators register fuel increase.
BOOST set ON
Pneumatically driven boost pump (in
AFT cell) is delivering fuel to both
engine CROSSFEED/ SHUTOFF
VALVES.
BOOST PUMP ON segment of C/W
panel illuminates. (Crossfeed must
be set to AFT TK in order to latch
BOOST switch.)
