99-23-09: Nose Landing Gear Wheel Rotation

99-23-09 AIRBUS INDUSTRIE: Amendment 39-11405. Docket 99-NM-106-AD. Applicability: Model A319, A320, and A321 series airplanes; except those airplanes on which Airbus Modification 23740 was accomplished during production, and those airplanes on which Airbus Service Bulletin A320-32-1197, dated October 9, 1998, or Revision 01, dated February 11, 1999, 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, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it. Compliance: Required as indicated, unless accomplished previously. To prevent uncommanded nose landing gear wheel rotation, due to defective seals in the wheel steering selector valve of the hydraulic control unit for the nose landing gear, which could result in reduced controllability of the airplane, accomplish the following: Modification (a) Within 12 months after the effective date of this AD, modify the electro-distributor for the nose wheel steering servo-control in accordance with Airbus Industrie Service Bulletin A320-32-1197, Revision 01, dated February 11, 1999. NOTE 2: Airbus Service Bulletin A320-32-1197 references MESSIER-BUGATTI Service Bulletin C24736-32-3166, dated December 4, 1998, as an additional source of service information for accomplishment of the modification. NOTE 3: Replacement of the by-pass valve in accordance with MESSIER-BUGATTI Service Bulletin C24736-32-3126, dated February 15, 1995, as revised by Change Notice Number 1, dated March 16, 1999, is considered acceptable for compliance with the action specified in paragraph (a) of this AD. Spares (b) As of the effective date of this AD, no person shall install a hydraulic control unit, part number C24736000 or C24736001, on any airplane, unless it has been modified in accordance with the actions required by paragraph (a) 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, FAA, Transport Airplane Directorate. 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 4: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 modification shall be done in accordance with Airbus Industrie Service Bulletin A320-32-1197, Revision 01, dated February 11, 1999. 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 FederalRegister, 800 North Capitol Street, NW., suite 700, Washington, DC. NOTE 5: The subject of this AD is addressed in French airworthiness directive 1999-124-129(B), dated March 24, 1999. (f) This amendment becomes effective on December 17, 1999.