TM 1-1520-238-T-7
10–38
10–7.
SYSTEM DESCRIPTION (cont)
10–7
M70-205
CROSSFEED
FUEL SWITCHES OFF
TO
ENG 1
TO
ENG 2
FWD
CELL
AFT
CELL
CROSSFEED
NORMAL OPEN
TO
ENG 1
TO
ENG 2
FWD
CELL
AFT
CELL
CROSSFEED
BOTH ENGINES
FEEDING FROM FWD
TO
ENG 1
TO
ENG 2
FWD
CELL
AFT
CELL
CROSSFEED
BOTH ENGINES
FEEDING FROM AFT
TO
ENG 1
TO
ENG 2
FWD
CELL
AFT
CELL
(BOTH VALVES GO TO THIS POSITION
DURING BOOST PUMP OPERATION)
FUEL CROSSFEED/
SHUTOFF VALVE
Figure 10–14.
Fuel Crossfeed/Shutoff Valves Functional Block Diagram
d. Fuel Quantity Indication/Transfer System.
(1) Purpose.
The purpose of the fuel quantity indication/transfer system is to provide the pilot and CPG
with fuel system status and to transfer fuel from one fuel cell to another in order to maintain center of gravity or in
case of fuel cell damage.
(2) System Operation.
(a) During fuel quantity transfer operation (fig. 10–15), 28 VDC is applied to the fuel transfer air valve.
The fuel transfer air valve controls PAS air used to drive the fuel transfer pump. The fuel transfer pump transfers
fuel from one fuel cell to another. When the TO FWD position on the FUEL panel is selected, PAS air drives the
fuel transfer pump, transferring fuel from the aft fuel cell to the forward fuel cell. When the TO AFT position on the
FUEL panel is selected, PAS air drives the fuel transfer pump, transferring fuel from the forward fuel cell to the aft
fuel cell. The fuel shutoff valve shuts off fuel flow when the fuel cells are full.
