Auto activation of cowl and wing anti-ice is inhibited:
When is the wing anti-ice system turned OFF?
The use of flaps in icing conditions is restricted to takeoff, approach and landing only.
Holding in icing conditions is limited to flaps UP only.
If the cowl anti-ice is operating from the automatic mode, and the ice detectors no longer detect ice, the cowl anti-ice will turn off:
The ICE DET TEST switch is on the SYSTEM TEST panel. When pressed, the switch illuminates TEST (blue) and initiates a test of the ice detection circuitry.
If the ice detector test is initiated while the wing anti-ice switches are selected to the AUTO position, the wing anti-ice system will be engaged for 10 seconds.
If the ice detector test is initiated while the wing anti-ice switches are selected to the AUTO position, the wing anti-ice system will be engaged for 3 seconds.
After engine start-up, the windshield heat control unit automatically performs a self-test of each circuit.
At initial power-up, the windshield heat control unit automatically performs a self-test of each circuit. If the self-test is passed, the front windshield is then powered by ramping from 0 to 100% in four minutes.
Operation of wing anti-icing is required if icing conditions are imminent, or immediately upon detection of ice formation on:
The windshield blower fan is powered by the ____, and the nozzle actuator is powered by the left main DC bus. When the control switch is pressed, the blue ON illuminates, the actuator extends the left and right blower nozzles, and the fan starts.
The nozzles direct high-velocity air (approximately 100 mph) to the bottom of each windshield. The high-velocity airstream removes beaded water droplets from the windshield and provides unobstructed visibility to the crewmembers during ground operation.
Engine vibrations may increase when icing occurs. The fan should normally shed the ice, and vibrations will return to a normal level. To help shed the ice when high vibration occurs and operational circumstances permit, one engine at a time may be quickly retarded to idle, held there for _____ and then accelerated to _____.
The power lever may then be returned to its original position.
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