Airworthiness Directive · Amendment 39-17843 · Fuselage
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 747-200B, 747-300, and 747-400 series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 747-53A2610, Revision 1, dated December 4, 2012.
We are superseding Airworthiness Directive (AD) 2007-16-19, which applied to certain The Boeing Company Model 747-200B, 747-300, and 747-400 series airplanes. AD 2007-16-19 required repetitive detailed inspections for cracking of the aft tension tie channels from body station (BS) 1120 to BS 1220 and from BS 880 to BS 1100, and corrective actions if necessary. AD 2007-16-19 also provided optional terminating action. This new AD retains the existing requirements, limits the area of the detailed inspection, adds repetitive surface high-frequency eddy current inspections, and mandates the previously optional terminating action. This AD was prompted by an analysis that indicated the need to mandate the previously optional modification. We are issuing this AD to prevent fatigue cracking of the tension ties, which could result in reduced structural integrity of the airplane and rapid depressurization of the airplane.
At the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-53A2610, Revision 1, dated December 4, 2012, except as specified in paragraph (j)(2) of this AD: Do detailed and surface high-frequency eddy current inspections for cracks in the tension ties at body station (BS) 880 to 1100, 1120, 1160, 1200, and 1220, and do all applicable corrective actions, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2610, Revision 1, dated December 4, 2012, except as required by paragraph (j)(3) of this AD. Do all applicable corrective actions before further flight. Repeat the inspections thereafter at the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-53A2610, Revision 1, dated December 4, 2012, until the tension ties have been modified as required by paragraph (h) of this AD or as specified in paragraph (i) of this AD. Repair or modification of a tension tie at any location in accordance with Part 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2610, Revision 1, dated December 4, 2012, terminates the repetitive inspection requirements of this AD for that tension tie location only.
At the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-53A2610, Revision 1, dated December 4, 2012, except as specified in paragraph (j)(2) of this AD: Modify the tension ties from BS 880 to 1100, and do all applicable related investigative and corrective actions, in accordance with Part 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2610, Revision 1, dated December 4, 2012, except as required by paragraph (j)(3) of this AD. Do all applicable related investigative and corrective actions before further flight. Modification as required by this paragraph terminates the repetitive inspection requirements of paragraph (g) of this AD for the affected tension tie location(s) only.
Modification of a tension tie at BS 1120 to 1220 in accordance with Boeing Service Bulletin 747-53A2559, Revision 1, dated August 4, 2011, except as required by paragraph (j)(4) of this AD, terminates the requirements of paragraph (g) of this AD for that tension tie location only. Paragraph (p) of AD 2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012), mandates the accomplishment of the modification and associated actions specified in Boeing Service Bulletin 747-53A2559, Revision 1, dated August 4, 2011.
(1) Paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-53A2610, Revision 1, dated December 4, 2012, specifies certain compliance times “after August 28, 2007.” August 28, 2007, is the effective date of AD 2007-16-19, Amendment 39-15158 (72 FR 45151, August 13, 2007).
(2) Where Boeing Alert Service Bulletin 747-53A2610, Revision 1, dated December 4, 2012, specifies a compliance time “after the Revision 1 date of this service bulletin,” this AD requires compliance within the specified time after the effective date of this AD.
(3) Where Boeing Alert Service Bulletin 747-53A2610, Revision 1, dated December 4, 2012, specifies to contact Boeing for certain repair instructions: Repair before further flight using a method approved in accordance with the procedures specified in paragraph (l) of this AD.
(4) Where Boeing Service Bulletin 747-53A2559, Revision 1, dated August 4, 2011, specifies to contact Boeing for repair instructions or additional modification requirements, repair of the cracking or additional actions must be done using a method approved in accordance with the procedures specified in paragraph (l) of this AD.
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
