ANTI ICE Panel

Question 1

What is accomplished if the WING anti ice pushbutton is selected ON while the aircraft is on the ground?

Answer 1

The system will self-test for 30 seconds, and then the valves will close until the aircraft is airborne.

Question 2

What does the WING FAULT light illumination on the ANTI ICE panel indicate?

Answer 2

• Valve disagreement. (comes on momentarily when valve in transit) • Low pressure

Question 3

What does the ENG 1(2) FAULT light illumination on the ANTI ICE panel indicate?

Answer 3

Valve disagreement (comes on momentarily when valve in transit)

Question 4

Describe the PROBE/WINDOW HEAT logic.

Answer 4

Probes and window heat come on automatically (probes LOW on ground/HIGH airborne) with at least one engine running or aircraft airborne.

Question 5

What part of the wing is heated?

Answer 5

Outboard 3 slats

Question 6

In what position do the WING and ENGINE anti ice valves fail if electrical power is lost?

Answer 6

• Wing – valves CLOSE

* Engine – valves OPEN

Question 7

What is the significance of high swept wings versus less swept wings in ice accumulation?

Answer 7

The more swept the wing, the less time for the moisture to attach.

Question 8

A flight crew is arriving to the aircraft in DTW early in the morning and notice that cockpit windows are frosted over. What should the flight crew do?

Answer 8

Select the PROBE/WINDOW HEAT on. This must be selected off prior to takeoff in order to regain normal system logic.

Question 9

The temperature outside is 2°C with visible moisture. What should the flight crew turn on?

Answer 9

ENG anti ice after engine start.

Question 10

After takeoff, when should the flight crew turn on the WING anti ice?

Answer 10

WING anti ice can be used after the aircraft is in a clean wing and when conditions warrant its use.

Question 11

Climbing through FL240 in visible moisture, the crew notices the TAT is - 22°C and the SAT is -45°C. What would be appropriate use of the ENG anti ice?

Answer 11

Engine anti ice may be turned OFF in this scenario. Engine anti ice is required when icing conditions exist or are expected except during climb or cruise when the SAT is below -40°C.

Question 12

Starting a descent out of FL350 with visible moisture, the TAT is -32°C and SAT is -53°C, what would be appropriate use of the ENG anti ice?

Answer 12

Engine anti ice should be turned ON in this scenario. Engine anti ice is required when icing conditions exist or are expected except during climb or cruise when the SAT is below -40°C.

Question 13

Descending through 10,000ft, the pilots notice ice accumulation on the cockpit windshield blades. What should they do?

Answer 13

Turn on the WING anti ice. WING anti ice may either be used to prevent or remove ice accumulation from the wing leading edges. After takeoff, WING anti ice can be used after the aircraft is in a clean wing configuration. Ice accumulation can be detected by observing the ice indicator located between the two cockpit windshields or by observing the windshield wipers blades.

Question 14

Can the WING anti ice be used on the approach and landing?

Answer 14

Yes but remember second segment climb performance could be affected if a go-around is performed.

Question 15

What is TAT?

Answer 15

Total Air Temperature is also called Indicated Air Temperature (IAT) or Ram Air Temperature (RAT)

Question 16

What is SAT?

Answer 16

Static Air Temperature is also called: Outside Air Temperature (OAT) or True Air Temperature

Question 17

Should a flight crew use TAT or SAT when determining whether to turn anti ice systems on?

Answer 17

Remember TAT indicates when to turn anti ice ON. SAT indicates when it may be able to be turned OFF.

Question 18

What is the difference between TAT and SAT known as?

Answer 18

The difference between TAT and SAT is called “ram rise (RR)” and is caused by compressibility and friction of the air at high velocities. See the sample effects of “ram rise (RR)” below:

Ground TAT +2 SAT+2 
10000ft TAT -6 SAT-17
18000ft TAT -13 SAT -33
FL240 TAT -23 SAT -45
FL350 TAT -28 SAT -54