DEICE / ANTICE PROCEDURES

Question 1

CA – When is a cold weather pre-flight inspection required?

Answer 1

The Cold Weather Preflight Inspection must be performed by a flight deck crewmember during the external walk-around inspection to determine the wing is free from frozen contaminants when:

1. The OAT is 5ºC or less, or
2. The wing fuel temperature is 0ºC or less, or
3. Atmospheric conditions conducive to icing exist, or
4. The aircraft has remained overnight and may have frozen contaminants due to exposure to frost or precipitation, which could involve the entire airframe, or
5. On any through flight where residual ice from the inbound flight may have accumulated on airframe surfaces or components, or
6. Cold soak ice is suspected in the fuel tank area.

Question 2

How is a cold weather pre-flight inspection conducted?

Answer 2

The Cold Weather Preflight Inspection consists of a visual and tactile check of the aircraft’s critical surfaces for frozen contaminants. Touch the wings.

Question 3

– What is the clean aircraft concept?

Answer 3

The Ground Deicing Program uses the clean aircraft concept, which means an aircraft must not takeoff when frost, ice, or snow is adhering to the wings, control surfaces, engine inlets, and other critical surfaces of the aircraft.
No contaminates on top of the wing. Allowing for only 1/8 inch frost on the bottom of wing. No failed fluid, nothing accumulating on the wings.

Question 4

Is it ever permissible to takeoff with contaminants on the under surface of the wing and if so what type of contaminant and maximum thickness?

Answer 4

Takeoff is permitted with frost adhering to the underside of the wing fuel tank area that is caused by cold soaked fuel:
a) CRJ - maximum 1/8 inch
Takeoff is permitted with frost on the upper surface of the fuselage through which it is possible to distinguish surface features.

Question 5

What is a Hold Over Time?

Answer 5

. The Holdover Time (HOT) range is an estimate of the time the deicing/anti-icing fluid is effective in preventing the formation of frost, ice, or the accumulation of snow on a treated surface. HOT begins when the final application of the deicing/anti-icing fluid commences and expires when the deicing/anti-icing fluid loses its effectiveness, e.g., when ice or snow begins to form on or in the fluid.

Question 6

FO – What is the Hold Over Time for the following conditions: Clarient Safe Wing MP IV Launch, OAT -10C, FZDZ?

Answer 6

27 min to

1 Hour and 16 min.

Question 7

CA – If the snowfall intensity is absent in an official weather observation, how is snowfall intensity determined when calculating a Hold Over Time?

Answer 7

Use snow fall intensity as a function of visibility.  
Snowfall Intensity (refer to eHOT app, PDF Viewer, Visibility Tables)

Question 8

FO – Is it advisable to use Snowfall Intensities as a Function of Prevailing Visibility chart when visibility is reduced by snowfall along with other forms of obscuration (FG, HZ, FU)?

Answer 8

Do not use! Table under those conditions overly estimates the actual snowfall.
Use of the FAA Snowfall Intensities as a Function of Prevailing Visibility Table under these conditions may needlessly overestimate the actual snowfall intensity. Therefore, the snowfall intensity being reported by the weather observer or automated surface observing system (ASOS), FMH-1 may be used.
During snow conditions alone, the use of Table 43 in determining snowfall intensities does not require pilot company coordination or company reporting procedures since this table is more conservative than the visibility table used by official weather observers in determining snowfall intensities.

Question 9

– During the Pre Deice/Anti-Ice check, what information is communicated from the flight crew to deice personnel?

Answer 9

1. Tail #
2. Brakes set
3. Aircraft configured for deicing
4. Type of fluids required
5. Surface to be treated

Question 10

Is the Flight deck deice / Anti-ice Checklist completed as challenge and response?

Answer 10

Yes

PRE DEICE / ANTI-ICE CHECK (Challenge and Response)

Question 11

What is a pretakeoff check and when is it required to be conducted?

Answer 11

All aircraft within the HOT and before take off.
a. A check of the aircraft’s representative surface for frozen contaminants. This check is conducted within the aircraft’s HOT, just prior to takeoff, and may be made by observing representative surfaces from whatever vantage point in the aircraft the PIC determines will give an accurate indication of the condition of the aircraft.
The Pretakeoff Check Procedure must be performed anytime the aircraft has been deiced/anti-iced, and an HOT has been established, to ensure critical surfaces remain free of frozen contaminants.

Question 12

What is normally the representative surface on SkyWest aircraft?

Answer 12

Left wing.
The surface that is checked while conducting the Pretakeoff Check. b. Not limited to a treated surface. c. Cannot be a heated surface. d. Normally the first surface to be deiced. e. Must be clearly seen to determine whether or not frozen contaminants are forming, or accumulating on the surface.
f. Normally the left wing leading edge and upper surface for all SkyWest aircraft.

Question 13

What action must be taken if the crewmember conducting the pretakeoff check is unable to determine if the representative surface is free of frozen contaminants?

Answer 13

De-Ice and Anti-Ice again.
When the flight deck crew is unable to determine that representative surfaces are free of frozen contaminants, the aircraft must be deiced again and anti-iced if precipitation is present and a new HOT is established before a subsequent takeoff.

Question 14

How do you determine if de-ice and/or anti-ice fluid has failed?

Answer 14

A fluid is considered failed when it is no longer able to absorb frozen precipitation. Under these circumstances, the assumption must be the contamination is adhering to the critical surfaces.
B. Failed fluids can be difficult to recognize as a layer of clear ice may have formed under the fluid, or ice crystals have formed in the fluid creating a surface roughness for takeoff that can significantly degrade aircraft performance or controllability. A failed fluid usually loses all its glossiness and resembles a dulled, crystalline appearance. The ability to discern structural detail (rivets, screws, seams) through the fluid is lost. While snowfall on a wing may be readily apparent, any clear ice that may have formed underneath is not.
D. Accumulated snow on a wing on top of deice/anti-ice fluids means the fluid has failed and will not blow off on the takeoff roll. Similarly, Type I fluid when used alone can refreeze in a matter of a few minutes after the holdover time has expired under certain precipitation conditions, especially freezing drizzle and freezing rain. Failed fluid takes on the appearance of a dull rough coating of frost.
E. The PIC directs the specific application requirements of fluids on aircraft surfaces, the execution of GDPM procedures, and is the final authority to assess and determine when the aircraft is properly deiced, anti-iced, and safe for takeoff.

Question 15

When is a pretakeoff contamination check required?

Answer 15

1. HOT has been exceeded
2. HOT is no longer valid due to changing weather conditions.
3. Heavy snow
4. Take off must occur within five minutes
   a. A check conducted after the HOT has been exceeded to ensure wings, control surfaces, and other critical surfaces are free of all frozen contaminants. This check must be completed within five minutes prior to takeoff.
   NOTE: The Pretakeoff Contamination Check is authorized for CRJ 700/900 and ERJ 175 aircraft only.

Question 16

How is a pretakeoff contamination check conducted?

Answer 16

The PIC
1. Sets the parking brake and ensures the aircraft remains static while the check is conducted.
2. turns the landing and taxi lights off
3. turns the wing inspection lights on.
4. Makes a cabin announcement to inform the passengers a flight deck crew member will be entering the cabin to conduct an inspection of the wings for the purpose of ensuring the absence of frozen contaminants prior to takeoff.
The Flight Deck Crew member doing the check.
1. Calls the FA and asks to have the ceiling lights switched to dim and all other cabin lights turned off during low light conditions.
2. Enters the cabin using the Pilot Out of Flight Deck Protocol.
3. Proceeds to the most advantageous row from which to view the wings upper surfaces.
4. Asks the passengers seated in the adjacent rows to stand in the aisle while the inspection is performed, as applicable.
5. During hours of darkness when using a flashlight, the flight deck crew member must shine the light through the adjacent window behind the adjacent row to illuminate the upper wing.
6. When the ceiling lights restrict visibility of the wing asks the FA to turn them off.
7. Determines if the wing upper surfaces are free of frozen contamination.
8. Asks Passengers to be re-seated and to fasten seat belts.
9. Using the Pilot Out of Flight Deck Protocol, regains entry to the flight deck.
10. Reports findings to the PIC, as applicable.
11. When the wing upper surface is free of frozen contaminants and takeoff will occur within five minutes, the aircraft is considered clean and may takeoff.

Question 17

What elements are required from ground crew to pilots?

Answer 17

Type of fluid, Percentage of fluid, Time of beginning of application, Post de-ice or anti-ice check complete.
ELEMENT A
A Specify type of fluid used (e.g., Type I or IV). Element A may be communicated prior to the start of fluid application.
ELEMENT B
B Specify the percentage of fluid within the fluid/water mixture (e.g., 100 = 100% fluid, 0% water and 75 = 75% fluid, 25% water).
NOTE: • Reporting the concentration of Type I fluids is not required. • Report the name (e.g., Clariant Safewing MP IV Launch) and concentration of Type II, III, and IV fluid/water mixture by volume.
• Type II and IV fluid only; the ratio will be 100% unless stated otherwise. • Element B may be communicated prior to the start of fluid application.
ELEMENT C
C Specify the time of the beginning of the final deicing/anti-icing step. Example: “START TIME IS ____.” State NOW or the time final fluid application begins (e.g., “8:47” or “FOUR MINUTES AGO”).
ELEMENT D
D. Not used by SkyWest Airlines
ELEMENT E
E. 1. Specify that post deicing and/or anti-icing check for clean surface is complete.
2. Before aircraft departure the “all clear “ indication can be verbal or visual.