Airworthiness Directive · Amendment 39-14576 · Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-300, 747-400, 747-400D, and 747SR Series Airplanes
Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-300, 747-400, 747-400D, and 747SR Series Airplanes
Superseded. A later AD replaced this one: AD 2006-09-06 R1. Comply with the one in force.
This AD applies to Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-300, 747-400, 747-400D, and 747SR series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 747-53A2408, Revision 1, dated April 4, 2002.
The FAA is superseding an existing airworthiness directive (AD), which applies to certain Boeing Model 747-100, -200, and -300 series airplanes. That AD currently requires repetitive inspections to detect cracking of certain lower lobe fuselage frames, and repair if necessary. This new AD retains all the requirements of the existing AD, and adds airplanes to the applicability. This AD results from reports indicating that fatigue cracks were found in lower lobe frames on the left side of the fuselage. We are issuing this AD to detect and correct fatigue cracking of certain lower lobe fuselage frames, which could lead to fatigue cracks in the fuselage skin, and consequent rapid decompression 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.
For airplanes on which the initial detailed internal inspection of the Section 46 lower lobe frames required by paragraph (f)(2) or (i)(2) of AD 2005-20-30, amendment 39-14327, has not been accomplished: Perform a detailed visual inspection to detect cracking of the lower lobe fuselage frames from Body Station 1820 to Body Station 2100, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2408, dated April 25, 1996; or Boeing Alert Service Bulletin 747-53A2408, Revision 1, dated April 4, 2002; as applicable; at the later of the applicable times specified in paragraph (f)(1), (f)(2), or (f)(3) of this AD.
(1) For all airplanes: Prior to the accumulation of 15,000 total flight cycles; or
(2) For Group 1 airplanes identified in Revision 1 of the service bulletin: Within 1,500 flight cycles or 18 months after May 5, 1999 (the effective date of AD 99-07-12), whichever occurs first.
(3) For Group 2 airplanes identified in Revision 1 of the service bulletin: Within 1,500 flight cycles or 18 months after the effective date of this AD, whichever occurs first.
Note 1: Paragraphs (f)(2) and (i)(2) of AD 2005-20-30 require a detailed inspection to detect cracks in the Section 46 lower lobe frames, in accordance with Boeing Service Bulletin 747-53A2349, Revision 2, dated April 3, 2003. The initial inspection is required prior to the accumulation of 22,000 total flight cycles; or within 1,000 flight cycles after June 11, 1993 (the effective date of AD 93-08-12, amendment 39-8559), or November 16, 2005 (the effective date of AD 2005-20-30), depending on previous inspections accomplished; whichever occurs later.
Note 2: For the purposes of this AD, a detailed inspection is: “An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirror, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate procedures may be required.”
If no cracking is detected during the inspection required by paragraph (f) of this AD, repeat the inspection thereafter at intervals not to exceed 3,000 flight cycles.
If any cracking is detected during any inspection required by paragraph (f) of this AD, prior to further flight, accomplish paragraphs (h)(1) and (h)(2) of this AD:
(1) Within 20 inches of the crack location on the frame, perform a detailed inspection of the adjacent structure to detect cracking in accordance with Boeing Service Bulletin 747-53A2349, Revision 2, dated April 3, 2003. If any cracking is detected during any detailed inspection done in accordance with paragraph (f) or (h)(1) of this AD, prior to further flight, repair in accordance with paragraph (h)(1)(i) or (h)(1)(ii) of this AD, as applicable.
(i) For Group 1 airplanes: Using a method approved in accordance with the procedures specified in paragraph (j) of this AD. The Boeing 747-400 Structural Repair Manual, Subject 53-10-04, Figure 67 or 90, is one approved method.
(ii) For Group 2 airplanes: Using a method approved in accordance with the procedures specified in paragraph (j) of this AD. The Boeing 747-400 Structural Repair Manual, Subject 53-60-07, Repair 1 or 2, is one approved method.
(2) Repeat the inspection required by paragraph (f) of this AD thereafter at intervals not to exceed 3,000 flight cycles.
(i) Accomplishment of the initial detailed inspection of the Section 46 lower lobe frames required by paragraph (f)(2) or (i)(2) of AD 2005-20-30 constitutes terminating action for the requirements of this AD only for airplanes identified in Boeing Alert Service Bulletin 747-53A2408, Revision 1, dated April 4, 2002, as Group 1 airplanes. Accomplishment of the initial detailed inspection of the Section 46 lower lobe frames required by paragraph (f) of AD 2006-05-02 constitutes terminating action for the requirements of this AD only for airplanes identified in Boeing Alert Service Bulletin 747-53A2408, Revision 1, dated April 4, 2002, as Group 2 airplanes.
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
