AD/B767/240 Horizontal Stabiliser Ballscrew (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 767 Series Aeroplanes

AD/B767/240 Horizontal Stabiliser Ballscrew 6/2008

Applicability:

All Model 767-200, -300, -300F, and -400ER aircraft.

Requirement:

Action in accordance with the technical requirements of FAA AD 2008-06-06 Amdt 39-15418.

Note:  Boeing Service Bulletins 767-27A0194 Revision 2 and 767-27A0195
Revision 2, or later FAA approved revisions, refer.

Compliance:

As specified in the Requirement document, with a revised effective date of
5 June 2008.

This Airworthiness Directive becomes effective on 5 June 2008.

Background:

The FAA received a report of extensive corrosion of a ballscrew in the drive mechanism of the horizontal stabiliser on a similar aircraft model.  An undetected failure of the primary load path for the ballscrew in the drive mechanism of the horizontal stabiliser and subsequent wear and failure of the secondary load path, could lead to loss of control of the horizontal stabiliser and consequent loss of control of the aircraft.

David Villiers
Delegate of the Civil Aviation Safety Authority

16 April 2008