COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY

SCHEDULE OF AIRWORTHINESS DIRECTIVES

Boeing 737 Series Aeroplanes

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 39.1 (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.

AD/B737/141 Forward Pressure Bulkhead 6/2000

Applicability: Model 737-100, -200, -300, -400, and -500 series aircraft, with line numbers 1

through 2737.

Requirement:  Action in accordance with the technical requirements of FAA AD 2000-05-29 Amdt 39-11639.

Note 1: Boeing Alert Service Bulletin (ASB) 737-53A1173 Revisions 1, 2, and 3 refer.

Note 2: Accomplishment of the preventive modifications of the centre web, vertical chords, and side chord areas, including the side chord areas at water line (WL) 207, of the forward pressure bulkhead, in accordance with Boeing ASB 737-53A1173, Revision 3, constitutes terminating action for the repetitive inspections requirements of this Directive for that area.

Note 3: Accomplishment of the preventive modification of the vertical chords and side chord areas at WL 195 in accordance with Boeing ASB 737-53A1173 Revision 2, constitutes terminating action for the repetitive inspections requirements of this Directive for the vertical chords and side chord at WL 195 only.

Compliance:  As specified in the Requirement document for the initial and repetitive inspections, with a revised effective date of 15 June 2000.

This Airworthiness Directive becomes effective on 15 June 2000.

Background:  The FAA received reports of numerous fatigue cracks found on critical areas of the forward pressure bulkhead. The actions specified by this Directive are intended to prevent such cracking, which could result in rapid decompression of the fuselage.

Bernard Malcolm Hole

Delegate of the Civil Aviation Safety Authority 5 May 2000

The above AD is notified in the Commonwealth of Australia Gazette on 17 May 2000.