AD/B747/392 Amdt 1 Fuselage Upper Lobe Doubler (Cth)

AIRWORTHINESS DIRECTIVE

On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/B747/392 and issues the following AD under subregulation 39.001(1) of CASR 1998.  The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Boeing 747 Series Aeroplanes

AD/B747/392 Amdt 1 Fuselage Upper Lobe Doubler 10/2011

Applicability:

Model 747-100, -100B, -100B SUD, -200B, -200C, -200F, -300, -400, -400D, -400F, 747SR and 747SP series aircraft; as identified in Boeing Alert Service Bulletin
747-53A2651, dated 12 June 2008, or later FAA approved revision.

Requirement:

Action in accordance with the requirements of FAA AD 2009-09-08 Amdt 39-15894.

1.    The FAA has approved the inspections and corrective actions with the corresponding compliance times specified in Tables 1 and 2, under paragraph 1.E. “Compliance”, of Service Bulletin 747-53A2651, Revision 1, dated
2 September 2010 as an Alternative Method of Compliance (AMOC) to the inspections and corrective actions with the corresponding compliance times specified in Table 1, paragraph 1.E. “Compliance” of Service Bulletin
747-53A2651, dated June 12, 2008, as required by paragraphs (f) and (g) of FAA AD 2009-09-08.

When this service bulletin specifies contacting Boeing for repair instructions, the repair instructions must be approved in accordance with paragraph (j) of the FAA AD.

All other requirements of FAA AD 2009-09-08 remain fully applicable and must be complied with.

2.    Other corrective actions (repairs) that are on an FAA form 8100-9 and approved in accordance with the procedures specified in paragraph (j) of FAA AD
2009-09-08, as an AMOC to the requirements of FAA AD 2009-09-08, may be carried out without the need to obtain an exclusion from CASA from this airworthiness directive.

Compliance:

As specified in paragraph 1.E. “Compliance” (Table 1 and 2) of Boeing S/B
747-53A2651 Rev 1, dated 2 September 2010 and as per FAA AD 2009-09-08 as applicable.

This Amendment becomes effective on 20 May 2011.

Background:

The FAA received reports of cracks in the radius detail of the fuselage upper lobe doublers.  Such cracking, unless detected and corrected, could result in significant degradation of the fuselage structure and reduce its ability to carry flight loads from the vertical stabiliser, which could adversely affect the controllability of the aircraft.

This amendment is to allow the use of Revision 1 of Boeing Service Bulletin
747-53A2651 as an Alternative Method of Compliance (AMOC) and to allow FAA form 8100-9 approved repairs, without the need for a CASA Exclusion.  There is some change to the requirements and compliance and these are specified in Paragraph 1E of Boeing Service Bulletin 747-53A2651, Rev 1, dated 2 September 2010.

The original issue of this AD became effective on 2 July 2009.

Charles Lenarcic
Delegate of the Civil Aviation Safety Authority

19 May 2011