Question

1. in which environment is aircraft structural ice most likely to have the highest accumulation rate?

a. cumulus clouds with below freezing temperatures.
b. freezing drizzle.
c. freezing rain.

Explanation:

• Freezing rain consists of larger liquid water droplets compared to freezing drizzle. When these larger droplets encounter a surface (like an aircraft) at or below freezing temperatures, they spread out more upon impact, leading to a relatively high accumulation rate of ice.
• Cumulus clouds with below - freezing temperatures may have smaller super - cooled water droplets (in the case of stratiform clouds) or a mix of ice and liquid (in cumulus). But the droplet size and the nature of the cloud (cumulus can have updrafts that might not be as conducive to continuous, high - rate accumulation as a steady precipitation like freezing rain) make their ice accumulation rate not as high as freezing rain in general.
• Freezing drizzle has smaller droplets. Smaller droplets mean less mass of water per unit volume, and thus a lower rate of ice accumulation compared to freezing rain.

Answer:

C. Freezing rain