In case of clear sky iceing is possible when

1. ✓An aircraft surface temperature is lower than the ambient air temperatureCorrect answer
2. An aircraft surface temperature is the same as the temperature of saturated air
3. An aircraft is moving in the dry air mass
4. An aircraft surface temperature is higher than the ambient air temperature

Explanation

Icing in clear air (hoar frost) can occur when an aircraft's surface temperature is lower than the ambient air temperature and below the frost point of the air.

🔒 The full EASA/ICAO explanation is available in the app.

Related questions

• The temperature at a altitude of 500 m may be higher than ground level, where there is
• TEMPO mean change
• In the group OVC070 encrypted clouds are
• The wind blows relatively to izohips

All topics: Meteorology →