99-23-16: Inspect Vertical Flange of Inboard Z-Stiffeners

99-23-16 AIRBUS INDUSTRIE: Amendment 39-11412. Docket 99-NM-184-AD. Applicability: Model A330 and A340 series airplanes; except those airplanes on which Airbus Modification 42605, or Airbus Service Bulletin A330-53-3019 (for Model A330 series airplanes) or A340-53-4028 (for Model A340 series airplanes) has been accomplished; certificated in any category. NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, ifthe unsafe condition has not been eliminated, the request should include specific proposed actions to address it. Compliance: Required as indicated, unless accomplished previously. To detect and correct fatigue cracking of the vertical flange of the inboard Z-stiffeners of the centerline panel of the fuselage belly fairing, which could result in reduced structural integrity of the belly fairing, accomplish the following: Repetitive Detailed Visual Inspections (a) Prior to the accumulation of 5,500 total flight cycles, or within 500 flight hours after the effective date of this AD, whichever occurs later, perform a detailed visual inspection to detect cracking of the vertical flange of the inboard Z-stiffeners of the centerline panel of the fuselage belly fairing, in accordance with Airbus Service Bulletin A330-53-3020 (for Model A330 series airplanes) or A340-53-4029 (for Model A340 series airplanes); each dated November 30, 1995; as applicable. NOTE 2: For thepurposes of this AD, a detailed visual inspection is defined as: "An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc. may be used. Surface cleaning and elaborate access procedures may be required." (1) If no cracking is detected, repeat the inspection thereafter at intervals not to exceed 5,500 flight cycles, until the requirements of paragraph (b) of this AD are accomplished. Corrective Actions (2) If any cracking is detected during any inspection required by this AD, prior to further flight, modify the vertical flange of both inboard Z-stiffeners of the centerline panel of the fuselage belly fairing and re-inspect the modified area to determine if cracking has been eliminated, in accordance with Airbus Service Bulletin A330-53-3019 (for Model A330 series airplanes) or A340-53-4028 (for Model A340 series airplanes); each dated November 30, 1995; as applicable. (i) If all cracking is not eliminated after accomplishment of the modification, prior to further flight, repair in accordance with a method approved by either the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate; or the Direction G n rale de l'Aviation Civile (DGAC) (or its delegated agent). For a repair method to be approved by the Manager, International Branch, ANM-116, as required by this paragraph, the Manager's approval letter must specifically reference this AD. (ii) If all cracking is eliminated after the accomplishment of the modification, no further action is required by this AD. Optional Terminating Action (b) Modification of the vertical flange of both inboard Z-stiffeners of the centerline panel of the fuselage belly fairing in accordance with Airbus ServiceBulletin A330-53-3019 (for Model A330 series airplanes) or A340-53-4028 (for Model A340 series airplanes); each dated November 30, 1995; as applicable; constitutes terminating action for the requirements of this AD. Alternative Methods of Compliance (c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, International Branch, ANM-116. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, International Branch, ANM-116. NOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116. Special Flight Permits (d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. Incorporation by Reference (e) The inspections and modification shall be done in accordance with Airbus Service Bulletin A330-53-3020, dated November 30, 1995; Airbus Service Bulletin A340-53-4029, dated November 30, 1995; Airbus Service Bulletin A330-53-3019, dated November 30, 1995; and Airbus Service Bulletin A340-53-4028, dated November 30, 1995; as applicable. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. NOTE 4: The subject of this AD is addressed in French airworthiness directives96-056-029 (B) and 96-057-042 (B); each dated March 13, 1996. (f) This amendment becomes effective on December 17, 1999.