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Notice of Proposed Rulemaking (NPRM).

The Federal Aviation Administration proposes to amend the airworthiness standards applicable to certain transport category airplanes certified for flight in icing conditions and the icing airworthiness standards applicable to certain aircraft engines. The proposed regulations would improve safety by addressing supercooled large drop icing conditions for transport category airplanes most affected by these icing conditions, mixed phase and ice crystal conditions for all transport category airplanes, and supercooled large drop, mixed phase, and ice crystal icing conditions for all turbine engines. These proposed regulations are the result of information gathered from a review of icing accidents and incidents.

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