Operations in Icing Flashcards
Icing conditions definition in flight
Icing conditions exist in flight at a TAT of 10 ̊C or below, and visible moisture in any form is encountered (such as clouds, rain, snow, sleet, or ice crystals), except when the SAT is -40 ̊C or below.
Visible moisture definition
Visible moisture includes, clouds, fog with visibility of 1 mile or less, rain, snow, sleet or ice crystals.
Operation of wing anti-ice system
Even small accumulations of ice on the wing leading edge can change the stall speed, stall characteristics or the warning margin provided by the stall protection computer.
Wing anti-ice ON (ground) without anti-icing fluids
Icing conditions exist on the ground when OAT is 5 ̊C or below and:
-visible moisture in any form (such as clouds, fog, or mist) is present below 400 feet AGL
-the runway is wet or contaminated, or
-in the presence of any precipitation (such as rain, snow, sleet, or ice crystals)
selected ON for the final two minutes of taxi prior to takeoff
Wing anti-ice Gound NOTE 1/2
L or R WING A/ICE caution messages may be posted during taxi but must be verified out and WING A/ICE ON advisory message posted, prior to takeoff. If wing anti-ice is not required for takeoff, it should be selected OFF just prior to takeoff.
Wing anti-ice ground NOTE 2/2
To prevent wing contamination from reverse jet blast, operating the thrust reversers during taxi operations on wet and contaminated surfaces should be avoided.
Wing anti-ice takeoff NOTE
If the wing anti-ice system is selected ON for takeoff, the cowl anti-ice system must also be selected ON.
Wing anti-ice ground (anti-ice applied)
The wing anti-ice system must only be selected and confirmed ON just prior to thrust increase for takeoff.
Wing anti-ice in flight
Wing anti-ice system must be on when:
- icing is annunciated by the icing detector system, or
- when in icing conditions and the airspeed is less than 230 KIAS, or
- when in icing conditions during descent from cruise altitude, or
- prior to extending flaps for approach when TAT is 10 ̊C (50 ̊F) or below.
When can you select wing anti-ice system select OFF
On final approach when fully configured for landing,
- ICE is not annunciated by the ice detection system, and
- not in icing conditions.
Cowl anti-ice system ON (ground) 1/2
The OAT is 10 ̊C or below and visible moisture in any form is present (such as fog with visibility of one mile (1,500 meters) or less, rain snow, sleet and ice crystals).
Cowl anti-ice system ON (ground) 2/2
The OAT is ̊C or below when operating on runways, ramps, or taxiways where surface snow, ice, standing water, or slush is present
Cowl anti-ice system ON (flight)
The engine cowl anti-ice system must be on when in icing conditions or when ICE is annunciated by the ice detector system.
