AD/B737/316 Floor Beam Web (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/B737/316 Floor Beam Web 5/2008 DM

Applicability:

Boeing Model 737-100, -200, -300, -400 and -500 series aircraft; as identified in Boeing Service Bulletin 737-57-1296, dated 13 June 2007.

Requirement:

Action in accordance with the technical requirements of FAA AD 2008-05-06, Amdt 39-15400.

Note:  Boeing Service Bulletin 737-57-1296, dated 13 June 2007, or later revision approved as an FAA AMOC, refers.

Compliance:

As specified in the requirement document with a revised effective date of 8 April 2008.

This Airworthiness Directive becomes effective on 8 April 2008.

Background:

This AD results from several reports of cracks in the centre wing box longitudinal floor beams, upper chord and lower chord.  This AD mandates inspections to detect and correct fatigue cracking of the upper and lower chords and web of the longitudinal floor beams, which could result in the loss of cabin pressure.

David Villiers
Delegate of the Civil Aviation Safety Authority

5 March 2008