ATSC 113 Fly C Proficiency knowledge test Exam Questions
and certified Answers 2025/2026
CAVOK - correct answer Ceiling and Visibility OK
Min. Requirements for VFR flight - correct answer -horizontal visibility of 3
statute miles or more, AND
-ceiling of 1000 ft above the airport
Marginal VFR - correct answer conditions which VFR is allowed, but
visibility is poor and/or cloud-base is low
Cloud base is between 1'000ft and 3'000ft and/or visibility is between 3 and
5 SM
VFR over the top - correct answer when a layer of clouds is below, but
above the clouds is clear
Requirements for IFR flight - correct answer -specially trained to use
instruments
- aircraft with proper instruments and radio
- proper charts
Cloud base is less than 1'000 ft and/or visibility is less than 3 SM
Obscurations - correct answer mist: hv >= 1km
Fog: visibilities <1km
, Smoke, volcanic ash, sand, haze, spray, and widespread dust, snow and
blowing snow
Mist... - correct answer small precipitation particles gently falling through
the air
Exists in relative humidity of 95% to 100%
Thin grey-coloured partial obscuration
Smoke... - correct answer c
Volcanic ash... - correct answer consists of microscopic rocks with sharp
edges (abrasive, like sandpaper)
St.Elmo's fire (sparks writhing across windscreen from built up electric
charge)
If enters turbines, can melt and re-solidify into glass-like coatings that
cause turbines to break
Emit many aerosols (eg. Sulfur dioxides), which causes red skies
Sand... - correct answer sandstorms/haboobs: from strong winds over
deserts
Abrasive effect (reducing visibility and creating static electric charges)
Haze... - correct answer consists of microscopic liquid water droplets
forming around a pollutant particle that attract water vapour
Haze particles can grow even when relative humidity is less than 100%
(begin forming/aerosol swelling at 75%)
and certified Answers 2025/2026
CAVOK - correct answer Ceiling and Visibility OK
Min. Requirements for VFR flight - correct answer -horizontal visibility of 3
statute miles or more, AND
-ceiling of 1000 ft above the airport
Marginal VFR - correct answer conditions which VFR is allowed, but
visibility is poor and/or cloud-base is low
Cloud base is between 1'000ft and 3'000ft and/or visibility is between 3 and
5 SM
VFR over the top - correct answer when a layer of clouds is below, but
above the clouds is clear
Requirements for IFR flight - correct answer -specially trained to use
instruments
- aircraft with proper instruments and radio
- proper charts
Cloud base is less than 1'000 ft and/or visibility is less than 3 SM
Obscurations - correct answer mist: hv >= 1km
Fog: visibilities <1km
, Smoke, volcanic ash, sand, haze, spray, and widespread dust, snow and
blowing snow
Mist... - correct answer small precipitation particles gently falling through
the air
Exists in relative humidity of 95% to 100%
Thin grey-coloured partial obscuration
Smoke... - correct answer c
Volcanic ash... - correct answer consists of microscopic rocks with sharp
edges (abrasive, like sandpaper)
St.Elmo's fire (sparks writhing across windscreen from built up electric
charge)
If enters turbines, can melt and re-solidify into glass-like coatings that
cause turbines to break
Emit many aerosols (eg. Sulfur dioxides), which causes red skies
Sand... - correct answer sandstorms/haboobs: from strong winds over
deserts
Abrasive effect (reducing visibility and creating static electric charges)
Haze... - correct answer consists of microscopic liquid water droplets
forming around a pollutant particle that attract water vapour
Haze particles can grow even when relative humidity is less than 100%
(begin forming/aerosol swelling at 75%)
