Atmospheric icing

Atmospheric icing occurs when water droplets in the air freeze on objects they contact. This is very dangerous on aircraft, as the built up ice changes the aerodynamics of the flight surfaces, and can cause loss of lift, with an increased risk of a subsequent crash.

Not all water freezes at 0°C or 32°F. Liquid water below this temperature is called supercooled, and such supercooled droplets cause the icing problems on aircraft. Below -20°C, icing is rare because clouds at these temperatures usually consist of ice particles rather than supercooled water droplets. Below -40^oC it is generally accepted that icing on aircraft is negligible.

Icing also occurs on towers, wind turbines, boats, oil rigs, trees and other objects exposed to low temperatures and water droplets.

See also

• Deicing
• Anti-icing
• Ice protection system

References

[[FAA] (U.S.) Advisory Circular 20-113]: Pilot Precautions and Procedures to be taken in Preventing Aircraft Reciprocating Engine Induction System and Fuel System Icing Problems

[[FAA] (U.S.) Advisory Circular 20-117]: Hazards Following Ground Deicing and Ground Operations in Conditions Conducive to Aircraft Icing

[[FAA] (U.S.) Advisory Circular 20-147]: Turbojet, Turboprop, and Turbofan Engine Induction System Icing and Ice Ingestion

Wind Energy in Cold Climates: Icing on wind turbines

External links

• Airline Regulators Grapple With Engine-Shutdown Peril WSJ April 7 2008