ATSC 113 EXAM STUDY GUIDE SOLVED
QUESTIONS UPDATED 2026
⫸ According to ICAO, ceiling is the height above ground level of the
lowest cloud base that is below .... Answer: 20,000 ft (6,000 m) and is
covering more than hald the sky (cloud coverage 5/8 or more aka
broken or overcast)
⫸ When would one report vertical visibility?. Answer: when there is
poor visibility that at the ground level is cannot be seen whether there
are clouds or not
ex. fog, forest-fire smoke or in a dust storm
⫸ CAVOK. Answer: Ceiling and Visibility OK (good for VFR flight)
⫸ What type of visibility is measured and reported at airports?.
Answer: horizontal visibility because it is the most relevant for safety
⫸ What is horizontal visibility?. Answer: how far away you can see a
black object during daytime or a bright light at night
reported as statute miles over land or nautical miles over the ocean
⫸ How to calculate when you will hit an obstacle while flying?.
Answer: visibility (km)/speed (km/h)
,⫸ RVR. Answer: Runway Visual Range
indicates how far ahead a pilot can see horizontally along a runway
centerline (usually reported only when visibilities are low)
⫸ How is vertical visibility determined?. Answer: distance an
observer can see vertically into an indefinite ceiling, the height
corresponding to the top of a ceiling light projector beam, the height
at which a ceiling balloon completely disappears during the presence
of an indefinite ceiling or the height determined by the sensor
algorithm at automated stations based on horizontal visibility
⫸ VMC. Answer: Visual Meteorological Conditions, name given to
weather that is good enough for you to fly
⫸ MVFR. Answer: Marginal Visual Flight Rules
VFR is allowed but visibility is poor and/or cloud base is low
⫸ IFC. Answer: instrument flight conditions
IFR but not VFR allowed
⫸ IMC. Answer: Instrument Meteorological Conditions
IFR but not VFR allowed
,⫸ VFR over the top. Answer: when flying VFR and there is a layer of
clouds beneath you so you cannot see the ground
⫸ freezing fog. Answer: when fog is made of supercooled liquid
water droplets (can freeze instantly when they touch something)
⫸ ice fog. Answer: made of tiny ice crystals
⫸ Fog can form due to two mechanisms. Answer: when water is
added to unsaturated (non-foggy) air
or
when unsaturated air is cooled to its dew-point temperature (temp at
which water vapour starts to condense into liquid droplets)
⫸ radiation fog. Answer: forms on cool, clear, calm nights when the
earth's surface cools rapidly by radiation
⫸ advection fog. Answer: Humid air blows over a colder surface,
causing the air temperature to decrease to the dew-point temperature
⫸ upslope fog. Answer: created by rising airmass along a land
surface, when air rises sufficiently and gets cold enough, fog forms
, ⫸ precipitation or frontal fog. Answer: formed by adding moisture
via evaporation from warm rain drops falling down through the
initially-unsaturated cooler air below cloud base (same as fractus
clouds)
can also form from waterfalls /other forms of water drops that
produce large amounts of spray
⫸ steam fog. Answer: when cold air moves over warm humid
surfaces
⫸ Hygroscopic. Answer: Absorbing moisture readily, a characteristic
of haze particles which allows them to grow
⫸ Common hygroscopic chemicals. Answer: salt, sulfates, nitrates,
biological (organic) chemicals
⫸ visibility of heavy snow. Answer: less than 0.4 km (0.25 miles)
⫸ visibility of moderate snow. Answer: 0.4 to 0.8 km (0.25 - 0.5
miles)
⫸ standard atmosphere. Answer: the average variation of pressure,
temperature and density with the altitude
QUESTIONS UPDATED 2026
⫸ According to ICAO, ceiling is the height above ground level of the
lowest cloud base that is below .... Answer: 20,000 ft (6,000 m) and is
covering more than hald the sky (cloud coverage 5/8 or more aka
broken or overcast)
⫸ When would one report vertical visibility?. Answer: when there is
poor visibility that at the ground level is cannot be seen whether there
are clouds or not
ex. fog, forest-fire smoke or in a dust storm
⫸ CAVOK. Answer: Ceiling and Visibility OK (good for VFR flight)
⫸ What type of visibility is measured and reported at airports?.
Answer: horizontal visibility because it is the most relevant for safety
⫸ What is horizontal visibility?. Answer: how far away you can see a
black object during daytime or a bright light at night
reported as statute miles over land or nautical miles over the ocean
⫸ How to calculate when you will hit an obstacle while flying?.
Answer: visibility (km)/speed (km/h)
,⫸ RVR. Answer: Runway Visual Range
indicates how far ahead a pilot can see horizontally along a runway
centerline (usually reported only when visibilities are low)
⫸ How is vertical visibility determined?. Answer: distance an
observer can see vertically into an indefinite ceiling, the height
corresponding to the top of a ceiling light projector beam, the height
at which a ceiling balloon completely disappears during the presence
of an indefinite ceiling or the height determined by the sensor
algorithm at automated stations based on horizontal visibility
⫸ VMC. Answer: Visual Meteorological Conditions, name given to
weather that is good enough for you to fly
⫸ MVFR. Answer: Marginal Visual Flight Rules
VFR is allowed but visibility is poor and/or cloud base is low
⫸ IFC. Answer: instrument flight conditions
IFR but not VFR allowed
⫸ IMC. Answer: Instrument Meteorological Conditions
IFR but not VFR allowed
,⫸ VFR over the top. Answer: when flying VFR and there is a layer of
clouds beneath you so you cannot see the ground
⫸ freezing fog. Answer: when fog is made of supercooled liquid
water droplets (can freeze instantly when they touch something)
⫸ ice fog. Answer: made of tiny ice crystals
⫸ Fog can form due to two mechanisms. Answer: when water is
added to unsaturated (non-foggy) air
or
when unsaturated air is cooled to its dew-point temperature (temp at
which water vapour starts to condense into liquid droplets)
⫸ radiation fog. Answer: forms on cool, clear, calm nights when the
earth's surface cools rapidly by radiation
⫸ advection fog. Answer: Humid air blows over a colder surface,
causing the air temperature to decrease to the dew-point temperature
⫸ upslope fog. Answer: created by rising airmass along a land
surface, when air rises sufficiently and gets cold enough, fog forms
, ⫸ precipitation or frontal fog. Answer: formed by adding moisture
via evaporation from warm rain drops falling down through the
initially-unsaturated cooler air below cloud base (same as fractus
clouds)
can also form from waterfalls /other forms of water drops that
produce large amounts of spray
⫸ steam fog. Answer: when cold air moves over warm humid
surfaces
⫸ Hygroscopic. Answer: Absorbing moisture readily, a characteristic
of haze particles which allows them to grow
⫸ Common hygroscopic chemicals. Answer: salt, sulfates, nitrates,
biological (organic) chemicals
⫸ visibility of heavy snow. Answer: less than 0.4 km (0.25 miles)
⫸ visibility of moderate snow. Answer: 0.4 to 0.8 km (0.25 - 0.5
miles)
⫸ standard atmosphere. Answer: the average variation of pressure,
temperature and density with the altitude
