Airworthiness Directive · Amendment 39-17264 · Nacelles/pylons
The Boeing Company Airplanes
(1) This AD applies to The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes, certificated in any category, as identified in Boeing Special Attention Service Bulletin 737-54-1043, Revision 2, dated November 4, 2011.
(2) Supplemental Type Certificate (STC) ST00830SE (http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/408E012E008616A7862578880060456C?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. For all other AMOC requests, the operator must request approval for an AMOC in accordance with the procedures specified in paragraph (h) of this AD.
We are superseding an existing airworthiness directive (AD) for certain The Boeing Company Model 737-600, -700, -700C, -800, and - 900 series airplanes. That AD currently requires replacing the drain tube assemblies and support clamps on the aft fairing of the engine struts. This new AD requires replacing the drain tube assembly of the left and right engine strut aft fairings with a new one, which includes an integral support clamp made of nickel alloy 625. This AD also adds airplanes to the applicability. This AD was prompted by a report of a broken drain tube assembly on the left engine strut at the clamp support location under the aft fairing compartment, inside the heat shield cavity of the aft fairing. There have also been reports of tube wear at this clamp location on additional airplanes. We are issuing this AD to prevent failure of the drain tube assemblies and clamps on the aft fairings of the engine struts. Such failure could allow leaked flammable fluids in the drain systems to discharge onto the heat shields of the aft fairings of the engine struts, which could result in an undetected and uncontrollable fire.
Within 60 months after the effective date of this AD, replace the drain tube assemblies and support clamps on the aft fairing of the struts of engines 1 and 2 with new drain tube assemblies and clamps, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 737-54-1043, Revision 2, dated November 4, 2011.
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