Ice and Rain Flashcards
Both engines provide bleed air to
each wing’s 3 mid-wing
leading edge slats
and the engine cowl inlet for anti-ice protection.
Electrical heat is used to anti-ice the
flight deck windows,
3 pitot probes,
two Angle Of Attack probes
and the Total Air Temperature probe.
Two probes located one on each side of the forward fuselage
provide automatic
ice detection in flight.
Automatic ice detection is inhibited
on the ground.
The anti-ice valves cannot be commanded open
by the automatic ice detection system with
the respective selectors positioned to OFF.
If ice is detected with selectors OFF,
an EICAS message ICING ENG and / or ICING WING is displayed.
When ice is initially encountered, an electric heater automatically starts to eliminate ice accumulation on the probes.
When either probe detects ice a second time,
After several cycles of the probe heater, the automatic ice detection system commands
the probe heater cycles on again and engine anti-ice valves open automatically to de-ice engine inlet cowls.
the wing anti-ice valves open to de-ice wing leading edges.
When ice is no longer detected on the probes, all anti-ice valves close automatically.
n flight, hot bleed air is supplied to three mid-wing leading edge slats on each wing.
Wing anti-ice is not available
on the ground.
Automatic (AUTO) wing anti-ice operation is inhibited, independent of Total Air Temperature (TAT), for up to
10 minutes after takeoff and while in the takeoff reference mode.
The automatic wing anti-ice inhibit is removed
10 minutes after takeoff or when climb thrust is selected,
whichever occurs first.
Manual wing anti-ice operation is not affected by the automatic operation inhibit.
All the flight deck windows are heated for anti-fogging.
The two forward windows are heated for
anti-ice protection during flight.
The two forward windows also have a backup power source for anti-fog protection.
Before electrical power is applied to the aircraft,
ensure the WIPER selectors are in
the OFF position. Do not operate the wipers on a dry window.
Three pitot probes and two Angle Of Attack probes
are heated electrically for anti-ice protection.
There is no flight deck control for these devices
and heat is applied when either engine is running.
The Total Air Temperature probe is also heated electrically but
this occurs when the aircraft is in flight.
When the engine anti-ice valve is opened either
by the selection of the anti-ice switch to ON
or the valves are opened by the automatic ice detection system,
the Engine Electronic Control (EEC) is
set to approach idle
and continuous engine ignition is
automatically turned on.
With the WING ANTI-ICE selector in the ON position
the wing anti-ice valves opened provided
the aircraft’s air ground sensors sense the aircraft is in the air mode.
If TAT is 10°C or above,
manual (ON) wing anti-ice operation is
inhibited until 5 minutes after takeoff.
The inhibit is removed anytime TAT drops below 10°C.
HEAT PITOT C advisory message means
the center pitot heat is inoperative.
In this situation, standby air data is unreliable in icing conditions.
The master caution has just sounded and the EICAS
is showing an ANTI-ICE LEAK ENG R caution.
In this situation, high temperature anti-ice bleed air is
detected to be leaking in the affected engine.
The engine anti-ice system automatically
isolates the heat source within approximately 2 min.
Anti-ice will not be available to the affected engine.
If the ANTI-ICE LEAK message remains displayed,
the checklist will instruct the crew to bring the power
on the affected engine to idle.
A bleed air leak from an idling engine will not —
cause engine damage.
avoid icing conditions as engine anti-ice is not available for that engine.
The EICAS now displays
an ANTI-ICE LOSS ENG R to indicate this.
