AD/F27/158 Main Landing Gear Drag Stay Units (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.

Fokker F27 Series Aeroplanes

AD/F27/158 Main Landing Gear Drag Stay Units 8/2005 DM

Applicability:

All Model F27 Mk 500 series aircraft, equipped with Messier-Dowty (formerly known as Dowty Aerospace Gloucester) Rough-Field Main Landing Gear that have Drag Stay units with part numbers 200261001, 200485001, or 200684001 installed; or re-identified units part number 200261002, 200485002, or 200684002 installed.

Requirement:

Action in accordance with paragraphs (a), (b), and (c), of Netherlands CAA AD NL-2005-003.

Note 1:  A copy of the Requirement document was provided with this Directive.

Note 2:  Dowty Aerospace Service Bulletins 32-82W Revision 2 and 32-169B Revision 2, or later UK CAA approved revision, refer; and Fokker Aircraft/Services Service Bulletins F27/32-167 and F27/32-171, or later CAA-NL approved revision, refer.

Compliance:

As specified in the Requirement document.

This Airworthiness Directive becomes effective on 8 June 2005.

Background:

Recently, following a MLG “unsafe” indication during flight, an emergency landing by an F27 Mk 500 aircraft resulted in a RH MLG collapse shortly after touchdown.  Investigation revealed that the RH Drag Stay unit had broken, and initiations of fatigue were found in the cracked surface.  An earlier similar incident lead to the issue of RLD AD 1993-169 and related SB F27/32-167, however, in the text of the related SB a statement said that “All F27 aircraft, except the Mk 500, could be equipped with part number 200261001, 200485001, or 200684001 drag stays”.  As a result of this confusion, there may be aircraft flying which are non-compliant or only partially compliant with the earlier AD.

David Villiers
Delegate of the Civil Aviation Safety Authority

3 June 2005