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/A320/190 Amdt 2 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. Airbus Industrie A319, A320 and A321 Series Aeroplanes AD/A320/190 Amdt 3 Engine Pylon Spar Box Ribs 3/2007 Applicability: All Model A318, A319, A320, and A321 aircraft, with Manufacturer Serial Number 0791, 1464, 1660, 1969, 1979, 2026, 2028, 2030, 2032, 2033, 2035, 2037, 2039, 2041, 2043, 2045, 2047, 2050 through 2053, 2055, 2057, 2059, 2060, 2062, 2064, 2066, 2067, 2069, 2071, 2072, 2074, 2078 through 2269, 2271 through 2506, 2508 through 2565, 2567 through 2580, 2582 through 2591, 2593 through 2597, 2600, 2601, 2605, 2607, 2610, or 2615. Requirement: Action in accordance with the requirements of EASA AD 2006-0136. Note: All Operators Telex (AOT) A320-54A1015 Revision 2, or later EASA approved revision, refers. Compliance: As specified in the Requirement document, with a revised effective date of 15 March 2007. This Amendment becomes effective on 15 March 2007. Background: The manufacturer recently discovered that certain engine pylon spar box ribs constructed of stainless steel material may not have been heat-treated in production, prior to installation in the pylon. The omission of the heat treatment operation results in a significant reduction of the material allowable yield stress. As a consequence, non heat-treated ribs may not meet all the certification requirements, especially for vertical gust. Amendment 1 clarified manual applicability in Requirement 1. Amendment 2 introduced Revision 1 of the Requirement document. No additional work was required. Amendment 3 is issued in response to a new EASA AD, which adjusts the means to comply with paragraph 1; and clarifies that once corrective actions in compliance with Airbus AOT A320-54A1015 original issue, Revision 1, or Revision 2 have been applied to any discrepant rib found on the aircraft, the change to the Airworthiness Limitation section of the Aircraft Flight Manual is no longer required, and no further action is mandated by this Directive. David Villiers Delegate of the Civil Aviation Safety Authority 1 February 2007