AD/BAe 146/134 Horizontal Stabiliser Lower Skin & Joint Plates (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.

British Aerospace BAe 146 Series Aeroplanes

AD/BAe 146/134 Horizontal Stabiliser Lower
Skin & Joint Plates 11/2008

Applicability:

BAe 146 Series 100 and 200 aircraft, serial numbers as identified in BAE Systems (Operations) Limited Inspection Service Bulletin ISB.55-020.

Requirement:

1.    Inspect the horizontal stabiliser lower skin and joint plates in accordance with paragraphs 2.C.(1) through 2.C.(3) of BAE Systems ISB.55-020 Initial issue, dated 11 December 2007 or later approved revision.

If no damage is found, drill and ream four (4) holes in accordance with paragraph 2.C.(4)(a) and inspect the holes in accordance with paragraph 2.C.(4)(b).

a.     If distortion or corrosion is found in the rivet holes, before further flight, contact BAE Systems for approved repair instructions to be accomplished prior to fitting of the rivets.

b.    If no distortion or corrosion is found, before further flight, install the four rivets in accordance with paragraph 2.C.(4)(c) of ISB.55-020.

2.    Repeat the inspection in accordance with paragraphs 2.C.(1) through 2.C.(3).

If damage is found during any inspection, before further flight, contact BAe Systems in accordance with paragraph 2.C.(5) of ISB.55.020 and accomplish an approved repair in accordance with paragraph 2.C.(6).

Accomplishment of the approved repair in accordance with BAE Systems Repair Information Leaflet HC551H9061 (at issue 2, dated 16 November 2007 or later revision) on the left and right sides of the horizontal stabiliser is terminating action for the repetitive inspection requirement (2) of this AD.

Note:  EASA AD 2008-0167, dated 2 September 2008, refers.

Compliance:

1.    No later than 6 months after 16 September 2008.

2.    At intervals not exceeding 24 months.

This Airworthiness Directive becomes effective on 23 October 2008.

Background:

BAE Systems has determined that in order to assure the continued structural integrity of the horizontal stabiliser lower skin and joint plates in the rib 1 area of certain
BAe 146 aircraft, a revised inspection programme for this area is considered necessary.  The disbonding of joints can lead to corrosion which, if undetected, could result in degradation of the structural integrity of the horizontal stabiliser.

Consequently, this AD requires the implementation of repetitive inspections and corrective actions, depending on inspection findings.  It also provides an approved repair as optional terminating action for the repetitive inspections.

David Villiers
Delegate of the Civil Aviation Safety Authority

8 September 2008