Learjet 60 - GRVTY XFR Switch

Pilot's
Manual

Learjet 60
full . The green FUEL
SYS light will illuminate
when AUX XFR is se-
lected and flash
whenever the EMPTY
light illuminates . Setting the
switch to Off
will close the right transfer valve,
de-energize the right
transfer pump, close
the crossflow valve,
enable the standby pumps,
and extinguish the
EMPTY light, if
illuminated . Actuation of the wing
float
switches has
no effect on the auxiliary
(right) fuel transfer sys-
tem . Therefore,
if the switch is not set to
OFF when the wing tanks are
full, fuel will
continue to circulate between
the fuselage and wing
tanks through the
wing expansion
and fuel transfer lines . When
the
fuselage tank
is emptied, a
pressure switch in the
right transfer line
will actuate
to illuminate
the EMPTY light . Whenever
the right trans-
fer
valve is open, a
vertical bar (on the
switch) will illuminate to an-
nunciate
the valve's open
status . If the transfer valve is
neither open
nor
closed, the vertical bar
will flash . An ON annunciation
(on the
switch) will illuminate
whenever power is
applied to the right trans-
fer
pump . The right
fuel transfer valve
operates on 28 VDC supplied
through the 5-amp
R JET PUMP-XFR
VALVE circuit breaker on the
copilot's circuit
breaker panel . Loss of
power to the right transfer
valve causes
the valve to remain in its last
position . The right transfer
pump operates
on 28 VDC supplied
through the 10-amp FUS TANK
AUX PUMP
circuit breaker on
the copilot's circuit breaker panel
. Both
the
valve and pump are
operative during EMER BUS mode .
GRVTY XFR SWITCH
The GRVTY XFR
switch, on the fuel control
panel, can be used to
transfer fuselage
fuel without using the
transfer pumps . The switch
is
an
alternate action type . When
GRVTY XFR is selected, both transfer
valves
will open, the crossflow valve
will open, and both standby
pumps will be
rendered inoperative . Fuel
will then gravity flow from
the fuselage tank
to the wing tanks until the
wings are full or the
wing and fuselage
tank heads are equal .
When using this method to
transfer fuel,
approximately 350 pounds
(159 kilograms) of fuel will
remain in the
fuselage tank and the EMPTY light
will be inoperative .
To assure all possible
fuel has been transferred, reference must be
made to the fuel quantity
indicator . The switch should be set to Off
when all fuel possible has been
transferred and during approach and
landing . The green FUEL SYS light
and
an ON
annunciation (on the
switch) will illuminate whenever gravity
transfer is selected . Gravity
transfer is operative during EMER BUS mode .
2-32
PM-123
Change 3