FUEL
Description
Aircraft Operations Manual
9/1.1
PAGE
3
Apr 01/15
the overhead fuel panel indicates the condition.
Pressure relief valves in the shutoff valve and the
suction check valves protect the feed line from ex-
cessive pressure due to thermal expansion when
the shutoff valve is closed.
2.3
Indicating systems
Electrical quantity indication
The quantity indication system is of the capacitance
type and consists of six probes and two indicators
for each tank plus a signal conditioner. The signal
conditioner converts the capacitance values of the
probes to indicator readings. Since the capacitance
depends on fuel level and density, the indicators will
show the weight of the fuel on board.
Due to fuel tank probe wiring, fuel quantity indication
may momentarily change (less than 1% of full scale
indication) when transmitting on COM 2.
NOTE
A fuel low level caution is provided for each tank.
When the fuel level is below 300lb
70lb (135 kg
30 kg) in a tank, a float switch in each inboard cell
will activate the master caution, L/R LOW LEVEL
light on the overhead panel and FUEL (CWP) light.
Mechanical quantity indication
There is a magnetic dipstick in each inboard tank
cell. The stick is accessible from the underside of
the wing. When lowered, the stick will engage
magnetically with a float device inside the tank. The
protruding length will indicate fuel level by the dip-
stick scale indexed in inches. The fuel quantity can
then be calculated from the dipstick index. See the
table below. The fuel quantities are calculated with
a fuel density of 6.7 lb/US gallon or 0.802 kg/l for a
levelled aircraft. The dipstick scale is ranging from 0
to 10.0 inches corresponding to 114
−
1038 lb or 52
−
472 kg.
Temperature indication
The fuel temperature indicator is provided to indi-
cate the temperature of the fuel being delivered to
the engines.
A temperature sensor is installed in the fuel system
upstream the engine fuel inlet. The temperature
signal is transmitted to an indicator on the overhead
panel. The indicator is shared with the battery tem-
perature indicator by means of a selector.
A11582
Fig. 2 Dipstick index