Airworthiness Directives; Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Bombardier Model CL-600-2B19 (Regional Jet series 100 & 400) airplanes, that requires a one-time inspection of the aft edge of the left and right main windshields to determine whether a certain placard is installed, and corrective actions if necessary. This action is necessary to prevent stress-related cracking of the windshields, and subsequent excessive frequency of abnormal procedures specified in the airplane flight manual and/or an emergency descent be accomplished, which poses an increased risk to passengers and crew members. This action is intended to address the identified unsafe condition.