AD/B727/160 Amdt 2 - Lower Skin Panel at the Lower Row of Fasteners of Fuselage Lap Joints (Cth)

AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/B767/160 Amdt 1 and issues the following AD under subregulation 39.1 (1) of CAR 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 727 Series Aeroplanes

AD/B727/160 Amdt 2

Lower Skin Panel at the Lower Row of Fasteners of Fuselage Lap Joints

8/2002

Applicability: Model Boeing 727 series aircraft, as listed in Boeing Service Bulletin 727-53A0222, Revision 1, including Appendix A, dated 15 March 2001.

Requirement: Action in accordance with the technical requirements of FAA AD 2002-07-09, Correction, Amdt 39-12703.

Compliance: As specified in the Requirement Document, with a revised effective date of 11 July 2002.

The revised effective date remains unchanged by this issue. This amendment becomes effective on 8 August 2002. Background: The FAA received a report of a 20- inch fatigue crack in the lower skin panel of the fuselage, between BS 540 and BS 560 common to stringer S26L, at the lower row of fasteners in the lap joint. Further investigation revealed multiple site fatigue damage (approximately 80 cracks) in the stringer S-4R lap joint of the lower fastener row of the lower skin panel. Three out of four aircraft inspected were found with such damage at the stringer S-4L joint. Preliminary results of the investigation revealed that the cracking had initiated at approximately 40,000 total flight cycles.