Airworthiness Directives; Bombardier, Inc. Airplanes

We are superseding an existing airworthiness directive (AD) for certain Bombardier, Inc. Model CL-600-2C10 (Regional Jet Series 700, 701, & 702), CL-600-2D15 (Regional Jet Series 705), and CL-600- 2D24 (Regional Jet Series 900) airplanes. That AD currently requires repetitive detailed inspections for cracking or deformation, or pulled or missing fasteners, on the lower panel of the left- and right-hand main landing gear (MLG) doors, as applicable, and corrective actions if necessary. That AD also reduces the repetitive inspection interval for certain airplanes. This new AD adds a new modification of the MLG door configuration, and removes certain airplanes from the applicability. This AD was prompted by further analysis of the MLG door by the manufacturer. We are issuing this AD to prevent failure of the lower panel of the MLG door, departure of the lower panel from the airplane, and consequent damage to airplane structure, which could adversely affect the airplane's continued safe flight and landing.