AD 2021-21-09 Retains The Requirements Of AD 2005-05-18, Revises The Applicability To Include Additional Airplanes

The FAA is superseding Airworthiness Directive (AD) 2005-05-18, which applied to certain The Boeing Company Model 737-600, -700, -700C, -800, and -900 series airplanes.

AD 2005-05-18 required repetitive inspections for cracking of the webs of the aft pressure bulkhead at a certain body station, and corrective action if necessary. This AD was prompted by cracking found in that inspection area on airplanes not identified in the applicability of AD 2005-05-18. This AD retains the requirements of AD 2005-05-18, revises the applicability to include additional airplanes, and adds an inspection for existing repairs on the newly added airplanes. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective December 13, 2021.

Supplementary Information: The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2005-05-18, Amendment 39-14007 (70 FR 12410, March 14, 2005) (AD 2005-05-18). AD 2005-05-18 applied to certain The Boeing Company Model 737-600, -700, -700C, -800, and -900 series airplanes. The NPRM published in the Federal Register on June 30, 2021 (86 FR 34660). The NPRM was prompted by cracking found in an inspection area on airplanes not identified in the applicability of AD 2005-05-18. In the NPRM, the FAA proposed to continue to require repetitive inspections for cracking of the webs of the aft pressure bulkhead at a certain body station, and corrective action if necessary. The NPRM also proposed to require revising the applicability to include additional airplanes, and adding an inspection for existing repairs on the newly added airplanes. The FAA is issuing this AD to address fatigue cracks in the webs of the aft pressure bulkhead, which could result in rapid decompression of the airplane.

FMI: www.regulations.gov