ANSI - American National Standards Institute
 Print this article  Previous Next 

Standards Protect Airplanes in the Harshest Winter Weather

New York, Dec 30, 2003

During the harsh winter months (and in regularly frosty climates), the air travel industry must go through rigorous safety precautions to ensure that equipment and systems are operating smoothly in even the cruelest of conditions. Standards for “de-icing” and “anti-icing” are critical to protecting the functioning of parts and the aerodynamics of planes, and help airline technicians and operators to comply with Federal Aviation Administration (FAA) rules.

According to FAA regulations, an airplane may not be operated in icy conditions “unless it is equipped with means for the prevention or removal of ice on windshields, wings, empennage, propellers, and other parts of the airplane where ice formation will adversely affect the safety of the airplane.” Ice and snow can potentially distort the curvature of an airplane wing’s surface and adversely affect aerodynamics and control mechanisms. To prevent this, airplanes are de-iced to remove environmental contaminants (ice, frost or snow) that may have accumulated, as well as anti-iced to prevent further accumulation.

To de-ice, technicians spray special fluids on the control surfaces of the airplane’s wings, tail, and at times on the engine inlets and fuselage from a basket mounted above a truck that drives alongside the plane. The fluids consist of combinations of ethylene or propylene glycol, hot water, and several additives. If the plane experiences a wait of more than fifteen minutes between de-icing and take-off, a second application is applied. Once airborne, the aircraft is able to keep its critical surfaces clear of contamination via special heaters.

The Society of Automotive Engineers (SAE), an ANSI member and accredited standards developer, has several publications regarding the process of de-icing. SAE AMS 1424E, Deicing/Anti-Icing Fluid, Aircraft, SAE Type 1, covers a deicing/anti-icing fluid that is generally used heated either diluted with water for the removal of, and time-limited protection against, deposits of frost, ice, and snow on exterior aircraft surfaces prior to takeoff.

In addition to the protection of aircraft protection, the runway surfaces must also be cleared of snow and ice for a safe takeoff. SAE AMS1431B, Compound, Solid Runaway and Taxiway Deicing/Anti-Icing, and SAE AMS1435, Fluid, Generic, Deicing/Anti-Icing Runways and Taxiways, cover deicing and anti-icing materials intended for use at airports on aircraft maneuvering areas, such as aprons, runways, and taxiways, for the prevention and removal of frozen deposits of snow, frost, and ice.