Icing Questions for PC JUN 2015

Question 1

What’s the influence of ISA Deviation on True Altitude?

Answer 1

The True Altitude will be Higher if ISA is Above STD

The True Altitude will be Lower if ISA is Below STD.

Question 2

With Low Temperatures conditions:

What are the Corrections to MSA?

Answer 2

If Surface Temperature is ISA-15 to ISA-30:

Add +10% to the MSA
If Surface Temperature is ISA-31 to ISA-50:

Add +20% to the MSA.

Question 3

With Low Temperatures conditions:

What are the corrections to IAF, FAF, MDA etc…?

Answer 3

When the report Temperature AT the Airport is Zero or Below:

• Apply the Temperature corrections of the QRH

Company Procedures:

Table CP-AWA 1/2.

Question 4

What happen when a clearance is issued by ATC with Low Temperatures conditions?

Answer 4

Once ATC has issued a clearance and the Pilot accepted it, it’s considered to be complied with.
If the Captain is not satisfied with it because of Low Temperatures Corrections, he must Request for Another Clearance.

Question 5

What restrictions applies to Final Approach Mode when Cold Weather Corrections applies? (8.1.1.2)

Answer 5

Final Approach Mode is Prohibited

Selected NAV/FPA or TRK/FPA must be used.

Question 6

What restriction apply to RNAV Approach with

LNAV/VNAV Minimum when cold-weather corrections applies? (8.1.1.2)

Answer 6

Each chart have a Minimum temperature under which Final Approach Mode is prohibited.

1) If the Temperature is Above the Minimum Chart

Temperature:

-> Final Approach Mode + LNAV/VNAV Minima

+ DA in the Box

• > No Temp Corr will apply in this Case
  2) If the Temperature is Below the Minimum Chart

Temperature:

-> NAV/FPA Mode + LNAV Minima + MDA in the Box

Or

-> TRK/FPA Mode + LNAV Minima + MDA in the Box

PS: 2) Is also possible in case 1).

Question 7

What’s the Clean Aircraft concept?

Answer 7

No Ice, Snow or Frost adhering to the wings, control surfaces, engines or other critical surfaces.

Question 8

When does the Hold other time (HOT) starts?

Answer 8

At the Beginning of the Anti-Icing (Second Phase) for Type 1.
OR
If a One Step product is used (Type 2 or 4) at the beginning of the De/Anti-icing process.

Question 9

Can we take off with the wings contaminated?

Answer 9

YES if the contamination is:

• Light-frost under the wings due to low fuel

temperature

• We must be able to see through it with a maximum

of 3 mm in thickness.

Question 10

Where can we have Frost on the Aircraft?

Answer 10

• Light-Frost under the wings due to Low Fuel

Temperature, must be able to see through it with a

maximum thickness of 3 mm
- Hoarfrost on the top of the fuselage with all Vents and

Ports Clear of any Contaminations.

Question 11

Can we have lower wing surface ice ridges?

Answer 11

No it’s prohibited.

Question 12

What can happen during Snow Removal or Long De-icing if the temperature is below -5° Celsius?

Answer 12

Water rundown may refreeze and disturb airflow around the static-ports.

Question 13

During Low Temperatures conditions what should be looked at during the walk around regarding the APU?

Answer 13

The APU Door Flap must be Free of Impacted Snow or Ice Before Starting the APU.

Question 14

What are the different types of Fluids and their characteristics?

Answer 14

• Type I High Glycol, Low Viscosity, Better for De-icing

Short HOT / Orange colour

• Type II 50% Glycol / Medium Viscosity / For De/Anti-

Icing / Medium HOT / Pale Straw Colour

• Type III Forbidden to use by KA
• Type IV Modified Type II with longer HOT.

Question 15

What should be done if a repeated application of Type 2 or 4 product is required?

Answer 15

A wash of the previous application is recommended with a Type 1 or Hot Water
This will avoid the re-freeze of the first application in some area of the Aircraft.

Question 16

What is the correlation between Hold Over Time (HOT) and Wings Inspections before Take-off, If HOT is 5 to 10 min?

Answer 16

If HOT is 5 to 10 min:

• Before 5 min no inspection required
• Between 5 to 10 min an inspection of the wings from

the middle of the cabin (Look for the small triangles,

try to have those seats Free of Pax)
- After 10 min an External Inspection is mandatory.

Question 17

What are the weather conditions for which the HOT values are not accessed?

Answer 17

• Hail
• Moderate Freezing Rain (FZRA)
• Heavy Freezing Rain (+FZRA)
• Heavy Snow.

Question 18

Can Hold Over Time (HOT) clock be stopped?

Answer 18

Only if the weather conditions Stop and Never Appears Again.
It’s NOT Possible to Stop and Restart the clock within HOT.

Question 19

What the difference between:
Light and Moderate weather conditions, if HOT is 5 to 10 min?

Answer 19

If HOT is 5 to 10 min:

Light Weather will be covered for 10 min

Moderate Weather will be covered for 5 min.

Question 20

What Anti-Icing is to be used if we encounter Ice Pellet?

Answer 20

Only Type 4 will allow a HOT for Ice Pellets
Refer to Chap. 8 Table (8.2.3 section).

Question 21

In the De/Anti-Icing Fluid, What are the effect of Lowest Operation Used Temperature (LOUT)?

Answer 21

• It is the Lowest Temp. at which we Can Use the Product

OR

• Sum of Actual Freezing Point + Freezing Buffer.

Question 22

Effect of Freezing Rain and Drizzle (FZRA/DZ) on APP and DEP?

Answer 22

• For Light Conditions -FZRA and –FZDZ

APP and DEP are Allowed
- For Moderate to Heavy Conditions FZRA/DZ +FZRA/DZ

APP and DEP are Prohibited

Question 23

Under which weather conditions a Take Off is Prohibited?

Answer 23

• Moderate to Heavy Freezing Rain or Drizzle
• Moderate Ice Pellets mixed with other form of

Precipitations
- Heavy Ice pellets, Snow Pellets of any intensity.

Question 24

What defines Icing Conditions?

Answer 24

TAT ≤ 10 and SAT ≥ - 40° C.

Question 25

What can we do if Engine Anti-Ice valve is stuck while on the ground (Amber on ECAM)?

Answer 25

Increase the thrust by 5% of N2.

Question 26

Conditions and Technic for the Ice Shedding procedure?

Answer 26

• Outside Air Temperature < 3° C.
• Every 15 min apply 50% of N1

Check there are No Engines Vibrations.
- Also to be applied at Line Up

Inform ATC of this requirement

(Longer time needed on the RWY).

Question 27

What are the precautions to be taken if Taxing in Icing Conditions?

Answer 27

• Maintain the Flaps Retracted until the holding point
• Taxi Speed below 10kt if Taxiways are Contaminated.

Question 28

At what speed should the Reversers be Stowed if there is Snow Covered Grounds?

Answer 28

The Reversers should be Stowed before 25 Kt.

Question 29

What are the Wing Anti-Ice Push Button (Pb) Characteristics:

• On Ground?
• In Flight?
• If it becomes Amber?
• If a Leak is Detected?
• If Electrical supply Fails?

Answer 29

• On the Ground after being depressed it will make a

Self-Test of 30 Sec. (Stay Blue during this time)
Then the Wing Anti-Ice valve will open again

automatically after T/O
- In Flight, hot air from the pneumatic system heats the

three outboard slats (3-4-5) of each wing
- If the Pb becomes amber it means the valve is Not in

Proper Position or a Low Pressure has been Detected
- If the system detects a Leak during normal operation

the affected side’s Wing Anti-Ice valve will

Automatically Close
- If the Electrical power supply Fails, the Valves Close.

Question 30

What are the Engine Anti-Ice Push Button (Pb) Characteristics:

• In Normal Operations?
• Air is Unavailable?
• If Electrical supply Fails?

Answer 30

• An Independent Air Bleed from the High Pressure

Compressor protects each engine nacelle from Ice.
- If Air is unavailable (Engine not running) the Valve

will automatically Close

• If Electrical power Fails, the Valve will Stay Open.