Ice Protection Systems

Question 1

What two types of anti-icing/de-icing systems are there onboard?

Answer 1

1) Electrical
2) Bleed Air

Question 2

What systems use electrical heating for their anti-icing?

Answer 2

1) Pitot tubes
2) AoA vanes
3) TAT probes
4) Windshields
5) Forward section of the prop spinner

Question 3

What systems use bleed air for their anti-icing/de-icing? What stage of compressor does bleed air come from?

Answer 3

1) Wing and Empennage leading edges
2) Vertical stabilizer
3) De-icing boot
4) 10th Stage

Question 4

Where is engine anti-icing supplied from? What does it supply in the engine?

Answer 4

• Directly from 14th stage compressor
• Supplies Engine and oil cooler inlet, compressor inlet guide vanes and torque meter shaft.

Question 5

What does the ice detection system achieve automatic operation of?

Answer 5

1) Wind/emp anti-ice/de-ice
2) Engine and oil cooler inlet anti-icing
3) Compressor inlet guide vane and torquemeter shaft
4) Prop spinner anti-icing and de-icing
5) Prop blade de-icing
6) Pneumatic de-icing boot

Question 6

How many ice detector probes are there on the aircraft?

Answer 6

1 each side

Question 7

When does Level 2 ice ACAWS display?

Answer 7

When approximately 1/2 inch of ice is detected.

Question 8

If the level 2 ice detected ACAWS message remains for more than 45 seconds, what is the rate of accumulation?

Answer 8

More than 1/2 inch per minute.

Question 9

What stage of engine compressor does the WING/EMP come from?

Answer 9

10th stage compressor

Question 10

How many zones is the WING/EMP system divided into? What are the zones? What is the controller behind the system?

Answer 10

7 zones.
verti tail. L and R horizontal stab. L and R inboard and outboard wing
BA/ECS

Question 11

Below what speed does wing/emp not function?

Answer 11

60 KIAS

Question 12

In the de-icing mode, what sequence of valve operation occurs?

Answer 12

Iterates through each zone for 60s then closesa nd moves onto the next.

Question 13

What is the difference between de-icing and anti-icing mode for WING/EMP?

Answer 13

In anti-icing, vertical stab remains open continuously.

Question 14

If WING/EMP test fails, above what temp is there a time limit before retesting and what is that time limit?

Answer 14

21 C, need to wait 10 minutes.

Question 15

What is the sequence for the vertical boot?

Answer 15

Inflates for 6 seconds, then deflates for 54 seconds.

Question 16

Is engine anti-ice available to an engine that has been shutdown?

Answer 16

No

Question 17

What compressor stage does bleed air for engine anti-ice come from?

Answer 17

14th stage

Question 18

What does the bleed air provide hot air to?

Answer 18

1) Engine and oil cooler intlet
2) Compressor inlet guide vanes
3) Torquemeter shaft

Question 19

At pressure altitudes > 3000 ft, if engine anti-ice is used for take-off what should the pilot do?

Answer 19

Let it stabilize for 3 minutes.