Summary
We propose to supersede an existing airworthiness directive (AD) that applies to 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. The existing AD currently requires a one-time inspection of the main landing gear (MLG) shock strut assemblies for part and serial numbers; for certain MLG shock strut assemblies, a one-time inspection of the torque link apex joint, and corrective actions if necessary; and, for certain MLG shock strut assemblies, replacement or rework of the apex nut. Since we issued that AD, we have determined that part and serial numbers for MLG shock strut assemblies for Model CL-600-2D15 and CL-600-2D24 airplanes were inadvertently omitted from certain requirements of the existing AD. This proposed AD would continue to require the actions in the existing AD, and would add the previously omitted part and serial numbers. We are proposing thisAD to detect and correct improper assembly and damage of the MLG torque link apex joint, which could cause heavy vibration during landing, consequent damage to MLG components, and subsequent collapse of the MLG.