BOMBARDIER BD-100-1A10, Руководство по эксплуатации

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AIR CONDITIONING/PRESSURIZATION
Sep 13/2004 Flight Crew Operating Manual Volume 2
REV 1 CSP 100-6
02-02-05
BLEED AIR MANAGEMENT
Bleed air management is primarily ensured through pilot selections on the control panel, and consists of the control and
monitoring of the valves controlling bleed air source selection. Bleed air valves are controlled from the AIR COND/
BLEED control panel and include the following:
- L (R) BLEED valves
- XBLEED
valve
- APU valve (via the ECU)
INTEGRATED AIR SYSTEM CONTROLLERS
The Integrated Air System Controllers (IASC)s ensure overall system control and monitoring. There are two units in the
aircraft, one located under the floor, and the other under the liner of the lavatory, above the floor. The units gather air con-
ditioning and bleed air control functions, and monitor cabin pressure and airframe ice protection functions. IASC 1 moni-
tors the left high pressure valve and left intermediate pressure valve; IASC 2 monitors the right high pressure valve and
right intermediate pressure valve.
Each IASC consists of two channels and monitors the following system operations:
- Channel A is dedicated to the Environmental Control System and Cabin Pressure Control
- Channel B is dedicated to the wing anti-icing monitoring and control and leak detection monitoring
Bleed Air for the wing anti-ice system is controlled at the ANTI-ICE control panel which is linked to the high pressure
valves.
ENGINE BLEED AIR PRESSURE REGULATION
Engine air pressure increases proportionally with N
2
compressor speed. The IPV limits the intermediate engine bleed pres-
sure to 50
±
3 psi. If a valve fails and manifold pressure exceeds 60 psi, a L (R) BLEED FAIL (C) CAS message is dis-
played.
APU/ENGINE BLEED SWITCHING
All bleed switching is done manually by the aircrew.
ENGINE START SEQUENCES
During engine starts on the ground, provided a bleed source has been selected, engaging the engine start switch will auto-
matically sequence the valves to isolate the air conditioning system and allow bleed air to flow to the air turbine starters.
When the L (R) STARTER switch is positioned to START, the following occurs:
- Cross bleed valve opens (if previously closed)
- Flow control valves close (if previously open)
- Associated start valve opens
- Engine air turbine starter (ATS) engages
When the engine achieves a self-sustaining rpm, the ATS disengages, the start valve closes, and the flow control and cross
bleed valves return to the previous position. Cross-engine bleed air (from one engine to the other) can be used to power the
starter. Interstage bleed air, taken from the selected engine is used for cross-engine bleed starting.
APU/ENGINE BLEED SWITCHING SEQUENCE
Takeoffs and landings are normally done with APU bleed air switch On and engine bleed air switch Off. During climb, the
pilot switches the XBLEED CLOSED, L BLEED On, APU bleed Off, R BLEED On and the APU OFF.
During approach, the pilot starts the APU and switches the R BLEED switch OFF, APU BLEED ON, L BLEED switch
OFF, and the XBLEED switch OPEN.
APU BLEED VALVE OPERATION
Bleed air from the APU can be used for engine starting and air conditioning. The APU electronic control unit (ECU) con-
trols the bleed valve and energizes the bleed air supply system and supplies compressed air from the APU power section
to the applicable aircraft system through the bleed air duct. The load control valve is connected to the compressor outlet of
the APU. When the load control valve is open, the ECU adjusts the butterfly plate position to supply the correct quantity
of bleed air. These adjustments are controlled by the required quantity of the bleed air load and the APU exhaust
gas temperature.