FAA revises icing standards for new transport airplanes
Goal: To fly safely in icing conditions
The U.S. Department of Transportation’s Federal Aviation Administration (FAA) has issued a final rule that broadens the coverage of its icing certification standards. The updated standards require U.S. manufacturers to show that transport airplanes can operate safely in freezing drizzle or freezing rain, conditions that constitute the icing environment known as “supercooled large drops” (SLD). The standard also includes ice crystal weather conditions as well.
SLD is less common than standard small droplet icing and can form ice on the airplane that exceeds the capability of current ice protection systems. The SLD could also severely impact the airplane’s performance and handling characteristics. Pilots usually encounter ice crystals, which can clog external air data sensors or lead to ice buildup in an engine, while they are flying around thunderstorms.