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 & 440) airplanes, that requires repetitive inspections for cracking of the upper and lower web of the engine support beam between fuselage station (FS) 625 and FS 640, and repair if necessary. This AD also provides an optional terminating action for the repetitive inspections. This action is necessary to prevent failure of the engine support beam, a principal structural element, which could result in reduced structural integrity of the airplane. This action is intended to address the identified unsafe condition.