24 questions on this topic, recalled by candidates after DGCA sittings between 2021 and 2026. Together they were asked 79 times; the most repeated come first. Pick a year to see only what was asked that year.
C. Severe
Over mountains, forced lifting adds a lot of supercooled water to altocumulus (such as the lenticular clouds of mountain waves), so the icing there can be severe.
B. There may be freezing rain at a higher level
Ice pellets are raindrops that fell through a cold layer and froze on the way down. So above you there is warm air with rain falling into sub-zero air - freezing rain is likely higher up.
C. Intermediate between these two
Real clouds contain a range of droplet sizes, so the ice that forms is usually a mixture of rime and glaze - the intermediate (mixed) type.
A. Not significant
Colder than about -20 °C most of the water in the cloud has frozen into ice crystals, which do not stick, so severe icing becomes unlikely.
B. Increases
Ice destroys the smooth wing profile (less lift, more drag) and adds weight, so the aircraft stalls at a higher speed - sometimes with little warning.
B. Large
Large droplets do not freeze instantly; they spread back over the surface before freezing, making a smooth, heavy, clear sheet that sticks hard. It is the most dangerous type.
A. Small
Small droplets freeze the instant they hit, trapping air between them - so rime is white, opaque, light and brittle, and builds forward into the airflow.
B. Light and porous
The air trapped between the tiny frozen droplets makes rime white, light and porous. That is also why it is easier to remove than glaze.
B. 0 °C and -20 °C
Supercooled water is most plentiful between 0 and -20 °C, so that is where most icing happens. Below -40 °C water cannot stay liquid.
C. Hoar frost
Hoar frost is vapour turning directly into ice on a surface below freezing - on a parked aircraft on a clear night, or on one descending from cold levels into moist air.
A. Ahead of
Ahead of a warm front, rain from the warm air above falls into the sub-zero cold air underneath, becoming supercooled and freezing on impact.
B. 0 °C and -40 °C
Supercooled drops can exist anywhere from 0 °C down to about -40 °C. With a mix of large and small drops you get a mixture of the two ice types.
C. -20 °C level
The strong updraughts in TCU carry plenty of supercooled water up to at least the -20 °C level, so the icing risk extends that high.
A. -25 °C level
Maximum supercooled liquid water concentration is found around the -25 °C level, and the heaviest ice formation in cloud is expected there too.
Our independent check could not confirm this answer from the official sources we hold; treat it with care and confirm with your instructor.
C. Glaze (clear ice)
Glaze is heavy, hard, sticks firmly, is hard to see and to shed, and spreads back over the wing, badly spoiling the aerofoil.
C. Cumulonimbus
The CB carries large supercooled drops high above the freezing level in strong updraughts - the recipe for severe clear icing.
C. Negligible
Ice crystals bounce off the airframe instead of freezing onto it. With almost no supercooled water, the high clouds carry negligible icing risk.
A. A warm front is approaching
Freezing rain needs warm air aloft over a sub-zero layer near the ground - the structure found ahead of a warm front in winter.
B. Light or moderate
The correct answer is: Light or moderate.
B. -20 °C
Below about -20 °C the proportion of supercooled droplets falls rapidly as they freeze into ice crystals, so the chance of icing drops off.
A. below the frost point
Hoar frost forms in clear, moist air when the airframe is colder than the frost point: water vapour turns straight to ice (sublimation) on the cold skin, as after a descent from cold altitude into humid air.
C. Mixture of Rime and Clear ice
Where a wide range of drop sizes is present - in As, Ns, Ac and towering Cu or Cb between 0 and -20 °C, and below 0 °C at a warm front - small drops freeze as rime and large ones as clear ice, so the two mix.
B. Large
Large supercooled drops do not freeze at once on impact. They spread back over the surface before freezing, forming a clear, heavy and hard-to-shed glaze. Small drops freeze instantly as rime.
A. Below the frost point
The frost point is the temperature at which air becomes saturated with respect to ICE. Cool a surface below it and water vapour turns straight into ice crystals on that surface - deposition, with no liquid stage. It needs no cloud and no precipitation, only a cold enough surface in clear air.
These are candidates' recollections, not official DGCA papers: wording can differ from the paper as set. Every answer was checked against the DGCA CARs, AIP India, ICAO documents or worked calculation (independent check completed 17 Oct 2026). Spotted a mistake? Tell us and we will check it against the source.