Summary
The FAA proposes to supersede Airworthiness Directive (AD) 2021-20-13, which applies to certain Bombardier, Inc., Model CL-600- 2B16 (604 Variant) airplanes. AD 2021-20-13 requires repetitive lubrication and repetitive detailed visual inspections (DVI) and non- destructive test (NDT) inspections of the main landing gear (MLG) shock strut lower pins, and replacement if necessary. Since the FAA issued AD 2021-20-13, Bombardier, Inc. developed a new design solution for this potential failure. This proposed AD would continue to require the lubrication and inspections specified in AD 2021-20-13 until the MLG shock strut assembly is modified by replacing the trailing arm bushing and installing new dynamic joint components. The FAA is proposing this AD to address the unsafe condition on these products.