Icing: DGCA Aviation Meteorology questions

Question 1

At temperatures of between 0°C and -10°C clouds will consist of:

Accepted Answer

mostly supercooled water droplets and a few ice crystals

Answer

entirely water droplets

Answer

entirely ice crystals

Answer

mostly water vapour

Question 2

Turbulent clouds are most serious from the icing standpoint because:

Accepted Answer

strong vertical currents mean that a predominance of large supercooled water droplets will be present

Answer

strong vertical currents mean that a predominance of small supercooled water droplets will be present

Answer

turbulent clouds produce hail which sticks to the aircraft

Answer

turbulent clouds indicate a low freezing level

Question 3

Hoar frost forms on an aircraft when:

Accepted Answer

the aircraft in subzero clear air suddenly enters a warmer moist region

Answer

the aircraft suddenly enters a cloud at below freezing temperature

Answer

the aircraft in subzero clear air suddenly enters a colder region

Answer

the aircraft suddenly enters a cloud which is at a higher temperature than the surrounding air

Question 4

Most cases of serious piston engine icing occur in cloud, fog, or precipitation with a temperature range between:

Accepted Answer

-10°C to +25°C

Answer

-18°C to +5°C

Answer

-10°C to 0°C

Answer

-20°C to +15°C

Question 5

Stratus cloud of limited depth at a temperature of -5°C will most likely give:

Accepted Answer

light to moderate rime ice

Answer

moderate to heavy rime ice

Answer

moderate to heavy glaze ice

Answer

light to moderate glaze ice

10 more questions in this chapter