Sub module 7.17: De-icing/Anti-icing of Aircraft
EASA MODULE 7A Sub Module 7.17 AIRCRAFT HANDLING AND STORAGE DE-ICING/ANTI-ICING OF AIRCRAFT Ice Types There are three main types of ice/frost that can affect an aircraft’s performance, Hoar Frost, Rime Ice and Glaze Ice. The temperature and weather conditions will determine the type of ice that forms, but all three types can have a detrimental effect. The Dew Point is the temperature at which moist air becomes saturated and deposits dew if in contact with a colder surface or the ground. Above ground, condensation into water droplets takes place. Hoar Frost is a deposit of ice crystals that form on an objectwhen the dew point is below freezing point. High humidity will normally produce hoar frost, as these are similar to conditions that produce dew. Hoar frost can form when the air temperature is greater than 0°C, but the aircraft skin temperature is less than 0°C. This type of frost produces a very rough surface which leads to turbulent airflow. Rime Ice is a light c...