AD/B737/336 Fuselage Upper Frame to Side Frame Splice (Cth)

AIRWORTHINESS DIRECTIVE

For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (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 737 Series Aeroplanes

AD/B737/336 Fuselage Upper Frame to Side Frame Splice 9/2008

Applicability:	Model 737-100, -200, -200C, -300, -400, and -500 series aircraft; as identified in Boeing Alert Service Bulletin 737-53A1261 dated 19 January 2006, or later FAA approved revision.
Requirement:	Action in accordance with the technical requirements of FAA AD 2008-13-12 Amdt 39-15575.
Compliance:	As specified in the Requirement document, with a revised effective date of 28 August 2008.
This Airworthiness Directive becomes effective on 28 August 2008.
Background:	The FAA received a report that the upper frame of the fuselage was severed between stringers S-13L and S-14L at station 747; and the adjacent frame at station 767 had a 1.3-inch long crack at the same stringer location.  Undetected fatigue cracking of the upper frame to side frame splice of the fuselage, could result in reduced structural integrity of the frame and adjacent lap joint.

David Villiers
Delegate of the Civil Aviation Safety Authority

14 July 2008