NTSB Issues Safety Recommendation to FAA Regarding Deice Boot Operations

The National Transportation Safety Board (NTSB) has issued a formal safety recommendation, designated as A-11-040 with reference number CEN09MA142, directed at the Federal Aviation Administration. This directive specifically targets operators subject to 14 Code of Federal Regulations Part 121, 135, and 91 subpart K who utilize airplanes equipped with pneumatic deice boots. The NSB advises that these operators should be prohibited from dispatching or deliberately operating such aircraft in known freezing rain or freezing drizzle, regardless of the intensity of the precipitation. This restriction applies unless the airplane manufacturer has explicitly demonstrated that the specific airplane model can operate safely under those exact conditions. The recommendation aims to mitigate risks associated with ice accumulation on deice boots when standard operational protocols may not suffice for safe flight.