TM 55-1510-215-10
4. Fuel
crossfeed
light
-
Check
9-10. Electrical System.
illuminated.
WARNING
NOTE
With a fuel firewall valve closed,
If battery overheats, do not open
the respective FUEL FAIL light may
battery compartment or attempt to
be illuminated, but the indication
disconnect or remove battery.
will lack significance due to the
Battery fluid will cause burns, and
closed position of the firewall
overheated battery could cause
valve.
thermal burns and may explode.
5. Transfer pump (dead engine) -
ON.
CAUTION
6. Auxiliary fuel pump (live engine) -
Check OFF (side receiving crossfeed).
Circuit breakers should not be
reset more than once until the
7. Crossfeed and fuel quantity -
cause of circuit malfunction has
Monitor.
been determined and corrected.
a. Electrical Power System Failure. In the event
e. Fuel Transfer - Manual. A no fuel transfer
both generators and the battery are shut off, the flaps
condition is indicated by illumination of a yellow R
will be inoperative, and the landing gear must be
FUEL XFR or L FUEL XFR light on the annunciator
extended manually. All systems (except the stall
panel, and the simultaneous flashing of both MASTER
warning horn) which utilize DC power for operation
CAUTION lights. Manual refill of a nacelle tank is
(including the AC power system) will be inoperative.
conducted with the TRANSFER PUMP switch ON,
and is initiated by holding the respective TRANSFER
TEST switch in the selected position (L or R). The
CAUTION
switch may or may not be released after fuel transfer
has started.
If the TRANSFER TEST switch is
released, fuel transfer will be stopped by either 24 or
Only one attempt should be made
57-gallon float switch. If the TRANSFER TEST switch
to restore an inoperative generator
is held ON, the transfer pump will continue to run
to use.
(overriding the float switches) until all available fuel is
transferred. The pump will then automatically shut off
b. Generator Failure. Either generator is capable
and the appropriate FUEL XFR light will illuminate on
of carrying the full load of normal aircraft electrical
the annunciator panel, indicating that no more fuel is
equipment. If one generator becomes inoperative, all
available for transfer. However, if transferable fuel
non-essential electrical equipment should be used
remains in the wing tanks after the nacelle tank is
judiciously to avoid overloading the remaining
filled to capacity, continuing to hold the TRANSFER
generator. Loads in excess of single generator output
TEST switch ON will only circulate fuel between the
will drain the battery, with the resultant loss of reserve
nacelle tank and the wing tanks.
and emergency power. The choice of equipment to be
used will be determined by existing conditions. The
NOTE
use of accessories which create a very high drain,
should be avoided. If both generators are shut off due
With fuel remaining in the wing
either to generator failure, ground fault or engine
tanks, illumination of the FUEL
failure, all equipment should be turned off to preserve
XFR light, after manual activation
battery power for extending the landing gear and wing
of the TRANSFER TEST switch,
flaps. The general location of failure within the aircraft
indicates transfer pump failure.
electrical system may be indicated by illumination of
the respective GEN OUT annunciator panel red light,
and the simultaneous flashing of the MASTER
WARNING lights.
9-13
