Which type of icing can be expected in cumuloform clouds?

• A. Clear
• B. Rime
• C. Mixed
• D. None

Answer: (B)

In icing, the kind that forms depends on droplet size and air temperature. Rime ice happens when small supercooled droplets freeze on contact with aircraft, creating a rough, milky-white coating that builds up quickly on leading edges. This is common in cumuloform clouds because they often contain many small supercooled droplets in cold air, with temperatures roughly between -15°C and -5°C. The rapid freezing of these small droplets leads to the characteristic rime ice. Clear icing, by comparison, requires larger droplets and warmer air near 0°C, which is less typical for cumulus conditions. Mixed icing would need both small and large droplets, which is not the standard scenario for cumuloform clouds. So, rime is the expected icing type in cumuloform clouds.