Engine Fuel System - BOMBARDIER Challenger 601-3A CL-600-2B16 Pilot Training Manual

OIL
TEMP
163
155
150
120
°C
90
60
30
0
-40
L
Figure 7-5. Oil Pressure and Temperature
Indicators
Operation
Figure 7-6 illustrates operation of the engine
oil system. The pressure element draws oil
from the tank, develops a pressure, and di-
rects the outflow through the bypass filter. A
relief valve limits pressure to a design value.
The pressure oil is directed through the oil
cooler and is then divided into two delivery
lines. One line is directed through a restric-
tor to the accessory gearbox, the front and
rear fan bearings, and the front compressor
bearing. The second delivery line supplies
high-pressure oil to the second and third com-
pressor bearings and to the front and rear tur-
bine bearings.
The six scavenge elements of the oil pump
provide direct scavenging of all bearings ex-
cept the front three. These forward bearings
are scavenged by a dual-element pump to re-
turn oil to the tank. The common scavenge
line enters the tank through a cyclone deaer-
ator. Oil tank pressure and bearing sump pres-
sure is controlled by an oil tank relief valve
and sump vent regulator acting as a vent and
pressure regulator.
OIL
PRESS
100
95
80
P
60
S
I
40
25
0
L
R L R
O
P
FOR TRAINING PURPOSES ONLY
FlightSafety Canada
CL-600-2B16 PILOT TRAINING MANUAL

ENGINE FUEL SYSTEM

General
The engine fuel system is an integrated hy-
dromechanical-electronic system. The fuel sys-
tem meters fuel to the combustor to provide for
starting, acceleration, deceleration, and full power
requirements under all operating conditions.
In addition, the fuel system operates the vari-
able-geometry system of the compressor to po-
sition inlet guide vanes and compressor stator
vanes to provide engine stall/surge protection.
Major Components
The major components of the fuel system include
an engine-driven LP pump, heat exchanger, a by-
pass filter, a dual-element HP pump, an inte-
grated hydromechanical-electronic fuel control
unit (FCU), a fuel flow distributor, and 18 fuel
nozzles in the combustor system.
LP Engine-Driven Pump
The LP engine-driven pump receives inlet fuel
at the standby pump or main ejector pressure,
increases this pressure, and divides the output
into two flows. One output goes to the heat ex-
changer and fuel filter before reaching the
primary HP element of this three-element
pump. The second output from the LP pump
goes to the secondary HP element. The primary
HP element develops the pressure necessary
for FCU operation. The secondary HP ele-
ment supplies the motive flow fuel to the pri-
mary and scavenge ejectors in the fuel tanks.
It also supplies motive flow fuel to the ecol-
ogy tank jet pump for scavenging of the fuel
drain system.
Fuel Heater
The fuel heater is an air-to-liquid heat ex-
changer. Fourteenth-stage bleed air is modu-
lated to the heater to raise the fuel temperature
to prevent water freezing problems. An auto-
matic bypass on the heater permits all fuel to
bypass if the pressure drop across the heater
exceeds a preset value or if the fuel tempera-
ture is already sufficiently high.
L t ée
L t d.
CL 601-3A 7-7