AD/B747/205 Amdt 2 - Lower Lobe Fuselage Frames (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/B747/205 Amdt 1 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/B747/205 Amdt 2 Lower Lobe Fuselage Frames 2/2007

Applicability: Model 747-100, -100B, -100B SUD, -200B, -300, -400, -400D, and 747SR series aircraft, as listed in Boeing Alert Service Bulletin 747-53A2408 Revision 1, or later FAA approved revision. Requirement: Action in accordance with the technical requirements of FAA AD 2006-09-06 R1 Amdt 39-14842. Compliance: As specified in the Requirement document, with a revised effective date of 15 February 2007. This Amendment becomes effective on 15 February 2007. Background: The FAA received reports indicating that fatigue cracks were found in lower lobe frames on the left side of the fuselage. Undetected fatigue cracking of lower lobe fuselage frames could lead to fatigue cracks in the fuselage skin, and result in rapid decompression of the aircraft.

Amendment 1 retained all the requirements of the original AD, while expanding aircraft applicability.

Amendment 2 is issued in response to a revision of the related FAA AD, which specifies appropriate service information for certain corrective actions.