The bleed-air manifolds (10th and 14th stages)
and their associated shutoff valves (SOV) are
located in the rear fuselage compartment. The
10th stage provides air to the air-conditioning
units, footwarmer/demist system, emergency
pressurization, pressurization jet pumps, and
air turbine starters. The 14th-stage bleed air
is used for cowl and wing anti-icing and to op-
erate the thrust reversers.
The APU compressor is capable of supplying air
to the 10th-stage bleed-air manifold when 10th-
stage engine bleed-air source is not selected.
An approved external air source can be used
to supply the 10th-stage bleed-air manifold
when engine and APU bleed-air supplies are
not available.
PNEUMATIC
SUBSYSTEMS
Nine pneumatic subsystems require air for ei-
ther control or operation. These subsystems are:
1. Engine starting
2. Thrust reversers
3. Cowl anti-icing
4. Emergency pressurization
5. Pressurization control jet pumps
6. Air conditioning
7. Footwarmers and windshield demisting
8. Wing anti-icing
9. Fuel heater
SUPPLY AND
DISTRIBUTION
T h e b l e e d - a i r s u p p l y a n d d i s t r i bu t i o n i s
achieved by a valving system consisting of
electropneumatic valves. These valves re-
quire electrical power and pneumatic pressure
to operate.
All bleed SOV are spring-loaded closed except
the 14th stage bleed SOV which are spring-
loaded open. Cowl anti-ice SOV are fail safe
open if loss of electrical power occurs.
BLEED-AIR VALVES
(10TH STAGE)
The 10th-stage bleed-air manifold supply is
controlled by three identical valves called the
left engine and right engine bleed-air shutoff
valves and the isolation valve. The engine
bleed-air shutoff valves permit flow in both di-
rections and are primarily used to control
bleed-air extraction from their associated en-
gine. The isolation valve also provides two-
way flow, and its function is to divide the
bleed-air manifold into a left and a right sec-
tion. Therefore, the isolation valve is nor-
mally closed in flight.
CONTROL AND INDICATION
The engine bleed-air valves and the isolation
valve respond to both manual and automatic
control systems.
Manual Control
Manual control is achieved by switchlights
on the bleed-air panel (Figure 9-1) located at
the lower center of the overhead panel. The
switchlights are labeled “L,” “R,” and “ISOL.”
Each engine bleed-air switchlight has a split
l eg e n d . T h e w h i t e u p p e r h a l f i s l a b e l e d
“BLEED CLOSED” and the red bottom half
is labeled “DUCT FAIL.” The ISOL switch-
light has a single green OPEN legend. The
engine bleed-air switchlights receive power
from DC bus 1 and DC bus 2, respectively. The
ISOL switchlight receives power from the DC
ESS bus.
When an electrical power source and a pneu-
matic pressure source are available, pushing
the L or R bleed-air switchlight (Figure 9-1)
FlightSafety Canada
L t é e
L t d .
CL-600-2B16 PILOT TRAINING MANUAL
9-2
CL 601-3A
FOR TRAINING PURPOSES ONLY