Airworthiness Directive · Amendment 39-16157 · Fuselage
The Boeing Company Model 747-200F, 747-200C, 747-400, 747-400D, and 747-400F Series Airplanes
This AD applies to all The Boeing Company Model 747-200F, 747-200C, 747-400, 747-400D, and 747-400F series airplanes; certificated in any category.
The FAA is superseding an existing airworthiness directive (AD), which applies to all Model 747-200F, 747-200C, 747-400, 747-400D, and 747-400F series airplanes. That AD currently requires repetitive inspections for cracking of certain fuselage internal structure (i.e., Sections 42 and 46 fuselage frames, upper deck floor beams, electronic bay access door cutout, nose wheel well, and main entry doors and door cutouts), and repair if necessary. This new AD requires additional repetitive inspections for cracking of certain fuselage structure (i.e., Section 41 fuselage frames where they connect to upper deck floor beams, and Section 41 fuselage frames between stringers (S-8 and S-12)), and related investigative/corrective actions if necessary. This AD also reduces the inspection threshold and repetitive inspection intervals for certain airplanes. This AD results from fatigue tests and analysis that identified additional areas of the fuselage where fatigue cracks can occur. We are issuing this AD to prevent the loss of structural integrity of the fuselage, which could result in rapid depressurization of the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
Do initial and repetitive inspections for fuselage cracks using applicable internal and external detailed inspection methods, and repair all cracks, by doing all the actions specified in the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2500, dated December 21, 2004; or Revision 1, dated September 25, 2008; except as required by paragraph (h) or provided by paragraph (l) of this AD. After the effective date of this AD, Boeing Alert Service Bulletin 747-53A2500, Revision 1, dated September 25, 2008, must be used. Do the initial and repetitive inspections at the applicable times specified in paragraph (g)(1) or (g)(2) of this AD, except as required by paragraph (j) of this AD. Repair any crack before further flight after detection.
(1) For Groups 1 through 7, 9, and 10 identified in Boeing Alert Service Bulletin 747-53A2500, Revision 1, dated September 25, 2008: Do the initial and repetitive inspections at the times specified in paragraph 1.E. of Boeing Alert Service Bulletin 747-53A2500, dated December 21, 2004, except as required by paragraph (i) of this AD.
(2) For Group 8 airplanes identified in Boeing Alert Service Bulletin 747-53A2500, Revision 1, dated September 25, 2008: Do the initial and repetitive inspections at the applicable time specified in paragraph 1.E. of Boeing Alert Service Bulletin 747-53A2500, Revision 1, dated September 25, 2008, except as required by paragraph (k) of this AD.
If any crack is found during any inspection required by this AD, and Boeing Alert Service Bulletin 747-53A2500, dated December 21, 2004; or Revision 1, dated September 25, 2008; specifies to contact Boeing for appropriate action: Before further flight, repair the crack using a method approved in accordance with the procedures specified in paragraph (m) of this AD.
(i) Where Boeing Alert Service Bulletin 747-53A2500, dated December 21, 2004; or Revision 1, dated September 25, 2008; specifies a compliance time after the date on the original issue of the service bulletin, this AD requires compliance within the specified compliance time after April 6, 2006 (the effective date of AD 2006-05-02).
For the additional inspection areas of Groups 1 through 7, 9, and 10 airplanes, identified in Boeing Alert Service Bulletin 747-53A2500, Revision 1, dated September 25, 2008: Do initial and repetitive inspections for cracking of the inspection areas, and, as applicable, repair cracking, by doing all the actions specified in the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2500, Revision 1, dated September 25, 2008; except as required by paragraph (h) of this AD. Do the initial and repetitive inspections at the times specified in paragraph 1.E. of Boeing Alert Service Bulletin 747-53A2500, Revision 1, dated September 25, 2008, except as required by paragraph (k) of this AD. Repair all cracking before further flight.
(k) Where Boeing Alert Service Bulletin 747-53A2500, Revision 1, dated September 25, 2008, specifies a compliance time after the date on Revision 1 of the service bulletin, this AD requires compliance within the specified compliance time after the effective date of this AD.
(l) For Group 8 airplanes, inspection of Areas 2 and 5 identified in Boeing Alert Service Bulletin 747-53A2500, dated December 21, 2004, as required by paragraph (g) of this AD, is no longer required.
