Hawker Beechcraft Hawker 800XP, Руководство по эксплуатации для пилотов

Страница: 112 / 923

Page 2-35
Pilot’s Operating Manual
Revision A2: Nov, 2004
Sub-section 2
ENGINES
Hawker 800XP Pro Line 21
Section III - SYSTEMS DESCRIPTION
The ENG ANTICE switches for the engine intake ice protection system may be selected ON at any
engine speed including the use of maximum take-off thrust for takeoff and go-around.
Engine inlet anti-icing should be used in flight continuously during expected icing conditions.
When icing conditions do not exist, the inlet anti-icing should not be used above 50° F (10° C) ambient
conditions for more than 10 seconds.
If anti-icing is required during takeoff, it should be turned ON prior to setting take-off power.
Each switch controls a servo-operated anti-icing on-off valve. When ON is selected, the following events
occur:
• The anti-icing valve opens and high pressure air is bled from the HP compressor and ducted
forward to anti-ice the nacelle inlet cowl.
• Electrical power is supplied to Pt
2
and Tt
2
sensor probe heaters.
• In flight, the digital fuel computers are reset to a schedule that incorporates a raised idle RPM.
A pressure switch, which operates at 6 psi, is tapped into the air bleed pipe from the engine. When the
air pressure is low, the switch operates and illuminates ENG 1 or 2 A/ICE annunciator on the MWS
panel. The anti-icing valve is energized to the closed position (with busbar energized and ENG ANTICE
switch selected to OFF), spring-biased to the open position. This provides anti-icing fail-safe operation
in the event of an electrical malfunction.
Prior to the opening of an anti-icing valve, or during any subsequent system failure, the pressure switch
will register a low pressure condition and the appropriate ENG A/ICE annunciator will be illuminated at
the MWS dim pre-set level.
The annunciator will remain illuminated at the dim level until the nacelle anti-icing air supply rises above
6 psi and the pressure switch contacts change over. Then the annunciator extinguishes. A timer in the
circuit makes sure the annunciator will brighten to full intensity, should the pressure switch not operate
within 2 seconds. The time delay also inhibits nuisance flashing of the annunciator during normal
system operation.
Power Supplies
DC supplies for the engine anti-icing system are taken from the PE busbar. The supplies to the pressure
switch are routed via the main gear weight-on wheels switch relay network.
ENG 1
A/ICE
ENG 2
A/ICE
and/or
MFD
MFD
PFD
PFD
Copilot Instrument Panel
Pilot Instrument Panel
Center Instrument
Panel