Ice and Rain

Question 1

What anti-ice systems are there?

Answer 1

1. Wing Anti Icing
2. Engine Anti-icing
3. Window heating
4. Probe hearing
5. Waste and water drain mast heating

Question 2

What is the hot pneumatic bleed air used to protect from icing?

Answer 2

1. Engine nacelles
2. Leading edge slats

Question 3

What does the electrical heating system protect from ice?

Answer 3

1. Flight deck window
2. Probes / Ports (AOA, Static, pitot, TAT)
3. Waste/water masts

Question 4

Wing Anti Icing - which slats are protected by pneumatic air and which slats are protected by heated leading edge?

Answer 4

1. Slats 3,4,5 (outboard) - pneumatic air
2. Slats 1 and 2 (inboard) - heated leading edge

Miscellaneous

In flight - when selected on - N1 limit reduced

On- ground - when selected on - does a test of the valves for 30 seconds

Question 5

Engine Anti Ice. Source of bleed air for engine nacelle?

Answer 5

Independent bleed air from the high pressure compressor of the engine

Question 6

What do the ENG ANTI ICE pb’s do?

Answer 6

1. Opens the anti ice valve in the engine
2. This allows hot compressed air into engine nacelle
3. Continuous ignition is automatically selected on
4. N1 limit automatically reduced

Question 7

Window Anti Ice. Key points:

Answer 7

1. Electrical heating for:
   a) windshield anti-icing
   b) side window defogging
2. Controlled by 2 x Window Heat Computers (WHC)
3. Normally in AUTO which commands:
   a) Window heat ON (in flight or on ground with one engine running

Question 8

Probe Heat key points:

Answer 8

1. Controlled via Probe Heat Computers
2. PHCs auto monitor and control heaters to protect probes

2B. In auto mode (on in flight / on while on ground will be heated with one engine running)

3. TAT probes are not heated on the ground

Question 9

When are the ENG 1 and ENF 2 ANTI ICE pbs turned on?

Answer 9

1. Taxi on ground with surface snow, standing water or slush that might be ingested into the engines
2. OAT at or below 10 degrees and visible moisture present
3. In flight - no need for anti ice when SAT is minus 40 degrees or below (save for descent when it should be on)

Question 10

When is wing anti ice selected on?

Answer 10

Where ice accretion observed on wings, ice detector probe (middle windshield) or fuselage