Questões ATP_pag317

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A. Wet snow.
 B. Freezing rain.
 C. Ice pellets.
Rain or drizzle is always formed in temperatures which are above freezing. Rain
falling through colder air may become supercooled, freezing on impact as freezing
rain.
Answer (A) is incorrect because wet snow is an indication that temperature is above
freezing at the present level. Answer (C) is incorrect because ice pellets indicate that
water has frozen, not that is has become supercooled.
1078. Which arctic flying hazard is caused when a cloud layer of uniform thickness overlies
a snow or ice covered surface?
 A. Ice fog.
 B. Whiteout.
 C. Blowing snow.
'Whiteout' is a visibility restricting phenomenon that occurs in the Arctic when a layer
of cloudiness of uniform thickness overlies a snow or ice covered surface. The result
is a loss of depth perception.
Answer (A) is incorrect because ice fog forms in moist air during extremely cold
conditions. It is not formed by a cloud layer overlying a snow-covered surface. Answer
(C) is incorrect because blowing snow is snow that is blown by light or greater winds,
causing decreased visibility. It is not formed by a cloud layer overlying a snow-
covered surface.
1079. What sources reflect the most accurate information on current and forecast icing
conditions?
 A. Low-Level Sig Weather Prog Chart, RADATs, and the Area Forecast.
 B. PIREPs, Area Forecast, and the Freezing Level Chart.
 C. AIRMET Zulu.
AIRMET Zulu describes moderate icing and provides freezing level heights.
Answer (A) is incorrect because Low-Level Sig Weather Prog Charts do not forecast
icing conditions but do forecast freezing levels. Answer (B) is incorrect because
although the Freezing Level Panel of the Composite Moisture Stability Chart gives
you the lowest observed freezing level, it does not indicate the presence of clouds or
precipitation, which must be present for icing to occur.
1080. Convective clouds which penetrate a stratus layer can produce which threat to
instrument flight?
 A. Freezing rain.
 B. Clear air turbulence.