Airworthiness Directive · Amendment 39-18881 · Fuselage
The Boeing Company Airplanes
This AD applies to Boeing Model 737-400 series airplanes, certificated in any category, as identified in Boeing Special Attention Service Bulletin 737-53-1187, Revision 3, dated July 10, 2015 (“SASB 737-53-1187 R3”).
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-400 series airplanes. This AD was prompted by an evaluation by the design approval holder (DAH), which indicates that the aft fuselage skin is subject to widespread fatigue damage (WFD), and reports of aft fuselage skin cracking. This AD requires repetitive inspections to detect cracking of the aft fuselage skin, inspections to detect missing or loose fasteners and any disbonding or cracking of bonded doublers, permanent repairs of time-limited repairs, related investigative and corrective actions if necessary, and skin panel replacement. We are issuing this AD to address the unsafe condition on these products.
At the applicable times specified in tables 1, 2, and 3 of paragraph 1.E., “Compliance,” of SASB 737-53-1187 R3, except as provided by paragraph (h)(1) and (h)(2) of this AD: Do the applicable inspections to detect cracks in the aft fuselage skin panels; and do all applicable related investigative and corrective actions; in accordance with the Accomplishment Instructions of SASB 737-53-1187 R3, except as required by paragraphs (h)(3) and (h)(4) of this AD. Do all applicable related investigative and corrective actions before further flight. Repeat the applicable inspections thereafter at the applicable intervals specified in tables 1, 2, and 3 of paragraph 1.E., “Compliance,” of SASB 737-53-1187 R3. Accomplishment of a repair in accordance with “Part 4: Repair” of the Accomplishment Instructions of SASB 737-53-1187 R3, except as required by paragraph (h)(3) of this AD, is terminating action for the repetitive inspections required by this paragraph at the repaired locations only.
(1) Where SASB 737-53-1187 R3, specifies compliance times “after the Revision 3 date of this service bulletin,” this AD requires compliance within the specified compliance times after the effective date of this AD.
(2) The Condition column of Paragraph 1.E., “Compliance,” of SASB 737-53-1187 R3, refers to airplanes in certain configurations as of the “issue date of Revision 3 of this service bulletin.” However, this AD applies to airplanes in the specified configurations as of the effective date of this AD.
(3) Where SASB 737-53-1187 R3 specifies contacting Boeing for repair instructions or work instructions, before further flight, repair or perform the work instructions using a method approved in accordance with the procedures specified in paragraph (n) of this AD, except as required by paragraph (h)(4) of this AD.
(4) For airplanes on which an operator has a record that a skin panel was replaced with a production skin panel before 53,000 total flight cycles: At the applicable time for the next inspection as specified in tables 1, 2, and 3 of paragraph 1.E., “Compliance,” of SASB 737-53-1187 R3, except as provided by paragraph (h)(1) and (h)(2) of this AD: Perform inspections and applicable corrective actions using a method approved in accordance with the procedures specified in paragraph (n) of this AD.
(1) For airplanes with a time-limited repair installed as specified in Boeing Service Bulletin 737-53-1187, Revision 2, dated May 9, 2007: At the applicable times specified in table 4 of paragraph 1.E., “Compliance,” of SASB 737-53-1187 R3, except as provided by paragraphs (h)(1) and (h)(2) of this AD: Do the actions specified in paragraphs (i)(1)(i) and (i)(1)(ii) of this AD.
(i) Do the applicable inspections to detect missing or loose fasteners and any disbonding or cracking of bonded doublers; and do all applicable related investigative and corrective actions; in accordance with the Accomplishment Instructions of SASB 737-53-1187 R3, except as required by paragraph (h)(3) of this AD. Do all applicable related investigative and corrective actions before further flight. Repeat the applicable inspections thereafter at the applicable intervals specified in table 4 of paragraph 1.E., “Compliance,” of SASB 737-53-1187 R3.
(ii) Make the time-limited repair permanent; and do all applicable related investigative and corrective actions; in accordance with Part 6 of the Accomplishment Instructions of SASB 737-53-1187 R3, except as required by paragraph (h)(3) of this AD. Do all applicable related investigative and corrective actions before further flight. Accomplishing the permanent repair required by this paragraph terminates the inspections required by paragraph (i)(1)(i) of this AD for the permanently repaired area only.
(2) For airplanes with a time-limited repair installed as specified in SASB 737-53-1187 R3: At the applicable times specified in table 5 of paragraph 1.E., “Compliance,” of SASB 737-53-1187 R3, except as provided by paragraph (h)(2) of this AD: Do the actions specified in paragraphs (i)(2)(i) and (i)(2)(ii) of this AD.
(i) Do the applicable inspections to detect missing or loose fasteners and any disbonding or cracking of bonded doublers; and do all applicable corrective actions; in accordance with the Accomplishment Instructions of SASB 737-53-1187 R3, except as required by paragraph (h)(3) of this AD. Do all applicable corrective actions before further flight. Repeat the applicable inspections thereafter at the applicable intervals specified in table 5 of paragraph 1.E., “Compliance,” of SASB 737-53-1187 R3.
(ii) Make the time-limited repair permanent; and do all applicable related investigative and corrective actions; in accordance with Part 6 of the Accomplishment Instructions of SASB 737-53-1187 R3, except as required by paragraph (h)(3) of this AD. Do all applicable related investigative and corrective actions before further flight. Accomplishing the permanent repair required by this paragraph terminates the inspections required by paragraph (i)(2)(i) of this AD for the permanently repaired area only.
For airplanes with an existing time-limited repair that was made permanent as specified in Boeing Service Bulletin 737-53-1187, Revision 2, dated May 9, 2007: At the applicable time specified in table 6 of paragraph 1.E., “Compliance,” of SASB 737-53-1187 R3, except as provided by paragraph (h)(1) of this AD: Modify the existing permanent repair; and do all applicable related investigative and corrective actions; in accordance with Part 6 of the Accomplishment Instructions of SASB 737-53-1187 R3, except as required by paragraph (h)(3) of this AD. Do all applicable related investigative and corrective actions before further flight.
Table 7 of paragraph 1.E., “Compliance,” of SASB 737-53-1187 R3, specifies post-repair airworthiness limitation inspections in compliance with 14 CFR 25.571(a)(3) at the repaired locations, which support compliance with 14 CFR 121.1109(c)(2) or 129.109(b)(2). As airworthiness limitations, these inspections are required by maintenance and operational rules. It is therefore unnecessary to mandate them in this AD. Deviations from these inspections require FAA approval, but do not require an alternative method of compliance.
At the later of the times specified in paragraphs (l)(1) and (1)(2) of this AD: Replace the applicable skin panels, and do all applicable related investigative and corrective actions, in accordance with the Accomplishment Instructions of SASB 737-53-1187 R3. Do all applicable related investigative and corrective actions before further flight. Doing the skin panel replacement required by this paragraph terminates the inspection requirements of paragraphs (g), (i), and (j) of this AD for that skin panel only, provided the skin panel replacement was done with a production skin panel after 53,000 total flight cycles, or with the skin panel replacement kit (S-20 to S-25 (left and right)) specified in Boeing Service Bulletin 737-53-1187.
(1) Before 60,000 total flight cycles, but not before 53,000 total flight cycles.
(2) Within 6,000 flight cycles after the effective date of this AD, but not before 53,000 total flight cycles.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Aircraft
