Airworthiness Directive · Amendment 39-21769 · Fuselage
The Boeing Company Airplanes
(1) This AD applies to The Boeing Company Model 737-600, -700, -700C, -800, and -900 series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 737-53A1251, Revision 2, dated January 20, 2021.
(2) Installation of Supplemental Type Certificate (STC) ST00830SE does not affect the ability to accomplish the actions required by this AD. Therefore, for airplanes on which STC ST00830SE is installed, a “change in product” alternative method of compliance (AMOC) approval request is not necessary to comply with the requirements of 14 CFR 39.17.
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.
Except as specified by paragraph (h) of this AD: At the applicable times specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 737-53A1251 Revision 2, dated January 20, 2021, do all applicable actions identified as “RC” (required for compliance) in, and in accordance with, the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1251, Revision 2, dated January 20, 2021. For Group 1 airplanes, as defined in Boeing Alert Service Bulletin 737-53A1251, Revision 2, dated January 20, 2021: Step 3.B.2. of the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1251, Revision 2, dated January 20, 2021, is an RC step, and the provisions of paragraphs (j)(5)(i) and (ii) of this AD apply.
(1) Where Boeing Alert Service Bulletin 737-53A1251, Revision 2, dated January 20, 2021, uses the phrase “the Revision 1 date of this service bulletin,” this AD requires using “the effective date of this AD.”
(2) Where Boeing Alert Service Bulletin 737-53A1251, Revision 2, dated January 20, 2021, specifies contacting Boeing for repair instructions or for alternative inspections: This AD requires doing the repair, or doing the alternative inspections and applicable on-condition actions using a method approved in accordance with the procedures specified in paragraph (j) of this AD.
