Airworthiness Directive · Amendment 39-18646 · 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, line number 1 through 1755, as identified in Boeing Alert Service Bulletin 737-53A1248, Revision 2, dated October 14, 2015.
(2) Installation of Supplemental Type Certificate (STC) ST00830SE (http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgSTC.nsf/0/38B606833BBD98B386257FAA00602538?OpenDocument&Highlight=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.
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-600, -700, -700C, -800, and -900 series airplanes. This AD was prompted by an evaluation by the design approval holder (DAH) indicating that the aft pressure bulkhead is subject to widespread fatigue damage (WFD). This AD requires repetitive inspections of the aft pressure bulkhead web for any cracking, crack indications, discrepant fastener holes, and corrosion; and corrective actions if necessary. We are issuing this AD to detect and correct cracks in the aft pressure bulkhead web, which could result in an uncontrolled decompression of the fuselage.
At the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 737-53A1248, Revision 2, dated October 14, 2015, or within 18 months after November 25, 2005 (the effective date of AD 2005-21-06), whichever occurs later: Do a low frequency eddy current (LFEC) or high frequency eddy current (HFEC) inspection, and a detailed inspection, of the aft and forward sides, as applicable, of the aft pressure bulkhead web at the Y chord, above and below stringer S-15L and stringer S-15R, to detect discrepancies (including cracking, crack indications, discrepant fastener holes, and corrosion), in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1248, Revision 2, dated October 14, 2015. Access and restoration procedures specified in the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1248, Revision 2, dated October 14, 2015, are not required by this AD. Operators may do those procedures following their maintenance practices.
(1) If no discrepancy is found: Repeat the inspections thereafter at the applicable times specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 737-53A1248, Revision 2, dated October 14, 2015.
(2) If any discrepancy is found: Do the actions specified in paragraphs (g)(2)(i) and (g)(2)(ii) of this AD.
(i) Repair the discrepancy before further flight using a method approved in accordance with the procedures specified in paragraph (j) of this AD.
(ii) On areas that are not repaired, repeat the inspections thereafter at the applicable times specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 737-53A1248, Revision 2, dated October 14, 2015.
Accomplishment of the initial inspections required by paragraph (g) of this AD terminates the requirements of AD 2005-21-06.
