Figure 9-5 illustrates the APU bleed-air sup-
ply. Unless prevented by the interlock de-
scribed above, when the APU is operating and
the APU RDY light is illuminated, pushing the
APU bleed-air switchlight will cause the APU
LCV to open and the APU surge valve to close.
The APU bleed-air is directed to the left side
of the bleed-air manifold. While operating in
this configuration, with the ISOL switch on and
the isolation valve open, pushing either one of
the engine bleed-air switchlights will cause the
APU LCV to close and the APU surge valve
to open. This protective interlock system pre-
vents reverse airflow to the APU compressor
even though the line is fitted with a check
valve. The isolation valve alone may be open
to permit the APU bleed air to pressurize the
right side of the bleed-air manifold. Both en-
gine bleed-air switches must remain off.
Initiating an engine start (either engine) while
the APU is supplying the manifold will auto-
matically open both engine bleed-air shutoff
valves, the isolation valve, and the selected
start valve. The four valves will remain open
until the start is terminated at approximately
55% N
2
.
An approved external air supply can be con-
nected to an adapter (Figure 9-6) located in a
covered access on the left side of the rear fuse-
lage. A flapper-type check valve in the adapter,
unseated when a connection is made, permits
flow in one direction only.
FlightSafety Canada
L t é e
L t d .
CL-600-2B16 PILOT TRAINING MANUAL
9-6
CL 601-3R
FOR TRAINING PURPOSES ONLY
LEFT
ACU
APU
RIGHT
ACU
ATS
ATS
10TH STAGE
BLEED AIR
PORTS
ISOL VALVE
PRESSURE
XDUCER
PRESSURIZATION
JET PUMP
RH ATS VALVE
10TH STAGE
BLEED AIR
PORTS
RH 10TH STAGE
BLEED-AIR
SOV
RH ACU
VALVE
LOAD
CONTROL
VALVE (LCV)
PRESSURE
XDUCER
EXT AIR
LH ACU
VALVE
BLEED AIR
LEGEND
LH 10TH STAGE
BLEED-AIR
SOV
LH ATS VALVE
Figure 9-5. Bleed-Air Supply—APU Operating