Flashcards in EMB-120 Ice and Rain Protection Deck (11):
What conditions does the ICE LOW SPEED alarm monitor?
• Less than 160 KIAS
• Leading edge boots ON
• Flaps up 0˚
Is prop heat available to us in the Electrical Emergency Mode?
What engine speed must be maintained in order for the leading edge deice boots to work?
How long does it take for all the leading edge deice boots to run through one complete inflation cycle?
The prop heat cycles on in the COLD position for?
How does the ice detector work?
The ice detector uses an ultrasonically vibrating probe to detect the presence of ice conditions. The probe is a nickel alloy tube mounted on the strut with one-inch exposed to the air stream. As the airplane enters an icing environment, the ice collected on the probe causes the frequency of the probe to decrease; generating a signal that activates the ICE CONDITION amber light on the multiple alarm panel. The ice detector is sensitive
enough to detect an ice accretion of as little as 0.5 mm (0.020 inch) of ice. The icing signal remains activated for 60 seconds. After 60 seconds the detector heater is activated to de-ice the probe. When the probe’s natural frequency is recovered, the heater is de-energized and a new detection cycle is initiated.
How do you turn on the ice detection system?
The ice detection system is powered by DC bus 2. The system is automatically turned on during airplane energization and remains activated during the entire flight. In case of system failure, an amber INOP light will illuminate on the ice detection system panel.
What do you hear and see when you test the ice detector system?
TEST SWITCH (MOMENTARY POSITION)
When actuated, it causes:
Illumination of the ice detection system INOP light.
Illumination of the ICE CONDITION and DE-ICE amber lights on the MAP.
Triggering of the aural warning.
The complete test lasts ~3 seconds.
The ICE MONITOR monitors what two things?
The ICE MONITOR monitors the timing sequence and presence of 16 psi. It generates NORMAL and INOP captions. It has no effect on the operation of the systems it monitors.
At what temperature do deice boots become brittle?
Boots become brittle at -40C. If at all possible, avoid flight in temperatures below -35C, and when descending, make every attempt to reach warmer altitudes before activating the boots.
At a temperature of -31C the probability of encountering ice that will adhere to the airframe is less than 5% and at - 40C it is less than 1%. Activation of the boots at these temperatures should be unnecessary.