AD/B737/343 Cracks in Fuselage Skin (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/B737/343 Cracks in Fuselage Skin 12/2008 DM

Applicability:

Boeing Model 737-300, -400, and -500 series airplanes, certificated in any category; as identified in Boeing Alert Service Bulletin 737-53A1293, dated August 13, 2008.

Requirement:

Action in accordance with the technical requirements of FAA AD 2008-19-03.

Note:  Boeing Alert Service Bulletin 737-53A1293 dated August 13, 2008 or later approved FAA revision refers.

Compliance:

As specified in the requirement document.

This Airworthiness Directive becomes effective on 16 October 2008.

Background:

The FAA have received reports of cracks in the fuselage skin common to stringer S-1 and between STA 400 and STA 460.  This directive is issued to detect and correct fatigue cracking of the fuselage skin panels at the chemical milling steps, which could result in sudden fracture and failure of the fuselage skin panels, and consequent rapid decompression of the airplane.

This directive requires repetitive external detailed inspections or non destructive inspections to detect cracks in the fuselage skin along the chemical milling steps at stringers S-1 and S-2R, between station (STA) 400 and STA 460, and repair if necessary.

David Villiers
Delegate of the Civil Aviation Safety Authority

3 October 2008