ANTI-ICE/WINDOW HEAT

Question 1

What happens when you turn the nacelle anti-ice switches on?

Answer 1

• NAI valve opens when the bleed air pressure is available.
• Engine igniters selected by the Auto Ignition selector and EEC operate continuously.
• PRV opens when anti-ice is ON.

Note:FCOM, VOL 2; 3.10.2

Question 2

What conditions would prevent the PRV from opening when nacelle anti-ice is on?

Answer 2

• Prior or present bleed air overheat
• Start valve not closed
• HP bleed air valve failed open

Note:FCOM, VOL 2; 3.10.2

Question 3

With the Nacelle Anti-Ice Switches in AUTO during icing conditions inflight, when will the system operate?

Answer 3

• When nacelle icing conditions exist

Note:FCOM, VOL 2; 3.10.2; 3.20.1

Question 4

When a Nacelle Anti-ice switch is ON, the respective nacelle anti-icing valve is:

Answer 4

• Commanded open.

Note:FCOM, VOL 2; 3.10.1

Question 5

How many ice detection probes are there, and where are they located?

Answer 5

• Two probes are located on the forward fuselage

Note:FCOM, VOL 2; 3.20.1

Question 6

If the engine bleed air valve is closed, and nacelle anti-ice is commanded, what is the source of bleed air for nacelle anti-ice?

Answer 6

• IP bleed only (HP bleed valve remains closed)

Note:FCOM, VOL 2; 3.20.1

Question 7

Is wing anti-ice effective with the leading edge flaps extended?

Answer 7

• No, wing anti-ice is ineffective when the LEF are not retracted.

Note:FCOM, VOL 2; 3.20.2

Question 8

Can you operate the wing anti –ice system on the ground?

Answer 8

• No, on the ground, the system is off and the wing anti-ice valves are closed

Note:FCOM, VOL 2; 3.10.3

Question 9

What part of the engine and wing are heated with NAI and WAI?
1

Answer 9

• Nacelle inlets
• Wing leading edges
Note:FCOM, VOL 2; 3.20.

Question 10

What is displayed on primary EICAS when the nacelle anti-ice and/or the wing anti-ice valve is open?

Answer 10

• “NAI” for nacelle anti-ice; and “WAI” for wing anti-ice.

Note:FCOM, VOL 2; 3.10.3; 3.20.1; 3.20.2

Question 11

Describe flight deck window heating systems.

Answer 11

• Flight deck windows are electrically heated
• Forward windshields have anti-ice protection on the exterior surfaces
• Forward windshields have anti-fogging on the interior surfaces.
• Side windows have controlled anti-fogging heating on the interior surfaces

Note:FCOM, VOL 2; 3.20.3

Question 12

What windows’ heating system is controlled by the window heat switches?

Answer 12

• Forward windshields only

Note:FCOM, VOL 2; 3.30.3

Question 13

Since the forward windshields are controlled by the window heat switches, how do we heat the side windows?

Answer 13

• Side window heating is automatic.
• No flight deck controls are provided
• System is powered whenever the AC electrical system is powered.

Note:FCOM, VOL 2; 3.20.3

Question 14

How many pitot-static probes are provided, and when are they heated?

Answer 14

• 4 pitot-static probes, electrically heated when any engine is operating.

Note:FCOM, VOL 2, 3.20.3

Question 15

How many angle of attack probes are provided, and when are they heated?

Answer 15

• 2 angle of attack probes are heated when any engine is operating.

Note:FCOM, VOL 2; 3.20.3

Question 16

How do we turn on the pitot heat?

Answer 16

They are on automatically anytime any engine is operating.