AD NUMBER: 2019-08-11

PRODUCT: All Bombardier, Inc., Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes.

ACTION: Final Rule.

SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2008-24-14, which applied to the airplanes listed above.

AD 2008-24-14 required revising the instructions for continued airworthiness to incorporate certain airworthiness limitations for the main landing gear (MLG) trunnion fitting assembly.

This AD requires revising the maintenance or inspection program, as applicable, to incorporate certain airworthiness limitations (AWLs). This AD also requires reworking the trunnion fitting in order to meet new structural safelife limits.

This AD was prompted by reports of cracks on the MLG trunnion fitting during fatigue testing; the introduction of new AWL tasks with revised inspection, modification, and safe-life requirements; and a determination that the trunnion fitting lower flange and both forward and aft bore holes are also subject to fatigue cracking.

DATES: This AD is effective July 11, 2019.

COST: The FAA estimates that this AD affects 460 airplanes of U.S. registry. Operators may incur the following costs in order to comply with this AD:

• Retained actions from AD 2008-24-14: 1 work-hour × $85 per hour = $85 per aircraft.
• New actions: Up to 178 work-hours × $85 per hour = Up to $15,130. Parts: 38,928. Cost per airplane: Up to $54,058.

FMI: AD