ANTI-ICE / DE-ICE

Types of Fluids

Type I:         

De-Icing

Type II & IV: 

Anti-Icing

Type I

Light reddish or light orange

Glycol based liquid

Mixed 50/50 with water

Heated to 140°C

Type II & IV

Thick Glycol

Type II is Clear

Type IV is Emerald Green

MAY NOT be mixed together

Used 100% strength

Holdover Time (HOT)

Based on chemical characteristics of each type of fluid.

The times derived from the charts need to be adjusted for factors such as, high wind, jet blast, different precipitation intensities, cold airplane surfaces.

The timing starts at the beginning of the final (protective) application of fluid.

ONE STEP PROCESS:

The airplane is sprayed with heated Type I fluid.  Provides de-icing action and some limited anti-icing protection.

TWO STEP PROCESS:

First de-iced with Type I fluid.

Type II or IV is applied within 3 minutes of completing Type I application

PreTakeoff Contamination Check

The check/procedure shall ensure the wings, control surfaces, engine inlets, and other critical surfaces are free of frost, ice, or snow.

A pre-takeoff check will be accomplished by the PIC during taxi-out any time:

(a)  Ground icing  conditions exist

(b)  Acft has been de-iced/anti-iced

(c)  HOT has been established

PreTakeoff Contamination Check:

When the HOT has been exceeded or when there is any doubt by the Captain concerning the airworthiness of the aircraft,takeoff should not be made until a pre-takeoff contamination check of the aircraft is accomplished.

Once completed, takeoff must be accomplished within 5 minutes.

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Limit ground operation of pitot/static heat to two minutes to preclude damage to the pitot tubes and angle-of-attack vane.

During sustained ground operations in freezing precipitation the engines should be operated for 15 seconds out of every 4 minutes at 60% N2 or above to preclude ice forming on engine probes or internal components.

Engine RPMs greater than 60% N2 is normally required to develop enough bleed air pressure (service air) to adequately inflate the boots.

It may require up to two minutes to extinquish the Wing Anti-Ice L/R annunciators with N2 set at approx. 70%.