Document ID: chunk:federal_register_of_legislation:F2009L00142:body:0:p1
Version: federal_register_of_legislation:F2009L00142
Segment Type: other
Provision Reference: 
Character Range: 0–3096

AIRWORTHINESS DIRECTIVE
On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/PA-31/118 Amdt 1 and issues the following 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.

Piper PA-31 Series Aeroplanes
AD/PA-31/118 Amdt 2  Aileron Spar  2/2009

Applicability:  All PA-31 Series.
Requirement:         1 (a) Remove the LH and RH ailerons from the aircraft, and remove the inboard and outboard hinge brackets and the control horn brackets.  Strip and clean the areas around the bracket attachments including the spar flanges, and inspect the visible surfaces of the front spar element (doubler) for cracks, using an approved dye penetrant inspection procedure.  Particular attention should be paid to the hinge bracket attachment and the horn bracket attachment areas; or,
                     (b) Inspect the aileron in accordance with an alternative scheme approved by the Authority.
                     2 (a) If any cracking or damage is identified, dismantle sufficient of the aileron structure to remove the spar doubler and gain good access to the main spar element, and the aft rib forward flange, in the vicinity of the identified defect.  Inspect all surfaces in the area using an approved dye penetrant inspection procedure.
                     (b) Repair cracking and damage in accordance with instructions approved by the holder of the USA type certificate, the Authority or an appropriate CAR 35 authorised person.
                Note 1:  Colour contrast dye penetrant used in accordance with Appendix II to
                CAO 108.10 is an approved inspection procedure.
                Note 2:  Cracking in these areas may be exacerbated by degradation of the control system stiffness (eg due to pivot bearing wear) and by aileron deflection during ground handling and pre-flight inspection.
Compliance:     Inspect before 5000 hours aileron time in service, and thereafter at intervals not exceeding 500 hours aileron time in service.
                Compliance with Amendment 1 of this airworthiness directive constitutes compliance with this Amendment.

             This Amendment becomes effective on 12 February 2009.
Background:  Numerous reports have been received of fatigue cracking in the aileron spar, spar doubler, and rib flanges, which appear to be caused by high out-of-plane stresses.  Cracking in these areas will degrade the strength of the hinge attachment and may have an adverse affect on the aileron flutter characteristics.
             Amendment 1 was raised to alleviate the