AD/B737/286 Fuselage Skin Scribe Lines (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/B737/286 Fuselage Skin Scribe Lines 6/2006

Applicability:

Model 737-100, -200, -200C, -300, -400, and -500 series aircraft.

Requirement:

Action in accordance with the technical requirements of FAA AD 2006-07-12 Amdt 39-14539.

Note:  Boeing Alert Service Bulletin 737-53A1262 original issue, or later FAA revision, refers.

Compliance:

As specified in the Requirement document, with a revised effective date of
8 June 2006.

This Airworthiness Directive becomes effective on 8 June 2006.

Background:

The FAA received reports of fuselage skin cracks adjacent to the skin lap joints on aircraft that had scribe lines.  Scribe line damage can occur at many other locations, including butt joints, external doublers, door scuff plates, the wing-to-body fairing, and areas of the fuselage where decals have been applied or removed.  Undetected fatigue cracks that propagate from scribe lines on pressurised structure could result in rapid decompression of the aircraft.

Richard Castles
Delegate of the Civil Aviation Safety Authority

28 April 2006