The FAA has published a final rule that changes preflight procedures for flights in wintry conditions. Effective Feb. 1, 2010, pilots of large general aviation aircraft, air taxis, and on-demand operations may no longer polish frost accumulations before takeoff. Frost-polishing is accomplished by scraping or buffing frost accumulations so as to obtain a smooth surface.
Currently, polishing of frost is permitted under FAR Part 91, subpart F (pertaining to large and turbine-powered multiengine airplanes, and fractional ownership aircraft), and under FAR parts 125 (airplanes having 20 or more seats and/or payloads of 6,000 pounds or greater) and 135 (air taxi and on-demand operations). The FAA final rule cites 12 accidents where airplanes with polished frost crashed shortly after takeoff. A 2004 United Kingdom recommendation to the FAA first urged that polishing of frost be banned following an accident in Birmingham, England. In 2006, an NTSB safety recommendation stressed that rules allowing frost polishing should be reversed.
Don’t forget to make sure your airplane is frost-, snow-, and ice-free before taking off this winter. Learn how to recognize the hazards of precipitation and ice, develop a strategy for avoidance, and react appropriately if you encounter unexpected conditions in the AOPA Air Safety Foundation interactive course Weather Wise: Precipitation and Icing.