AD 96-01-52 SUPERSEDED

96-01-52 AIRBUS: Amendment 39-9491. Docket 96-NM-03-AD.

Applicability: Model A310 and A300-600 series airplanes; equipped with a trimmable horizontal stabilizer (THS) actuator having part number (P/N) 47142-201 or P/N 47142-203; 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 use the authority provided in paragraph (c) of this AD to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition; or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any airplane from the applicability of this AD.

Compliance: Required as indicated, unless accomplished previously.

To prevent runaway of the horizontal stabilizer to its full up or down position, subsequent reduced maneuvering capability, and a potential pitch upset, accomplish the following:

(a) Within 12 days after the effective date of this AD, perform an inspection to ensure correct synchronization of the hydraulic control valves of the trimmable horizontal stabilizer (THS) actuator, in accordance with paragraph 4.2.2.1 of Airbus All Operators Telex (AOT) 27-21, Revision 1, dated January 5, 1996.

(1) If the actuator is synchronized correctly, prior to further flight, perform a functional test of the THS in accordance with paragraph 4.2.2.1 of the AOT. Thereafter, repeat the inspection required by paragraph (a) of thisAD at intervals not to exceed 500 hours time-in- service.

(2) If the actuator is desynchronized slightly, as specified in the AOT, prior to further flight, adjust the synchronization, and perform a functional test of the THS, in accordance with paragraph 4.2.2.2 of the AOT. Thereafter, repeat the inspection required by paragraph (a) of this AD at intervals not to exceed 500 hours time-in-service.

(3) If the actuator is desynchronized significantly, as specified in the AOT, prior to further flight, accomplish either paragraph (a)(3)(i) or (a)(3)(ii) of this AD. Prior to further flight following the accomplishment of either of those paragraphs, adjust the synchronization, and perform a functional test of the THS, in accordance with paragraph 4.2.2.3 of the AOT. Thereafter, repeat the inspection required by paragraph (a) of this AD at intervals not to exceed 500 hours time-in-service.

(i) Remove and replace the hydraulic motors of the horizontal stabilizer actuator (HSA) with new or serviceable motors in accordance with procedures specified in the Airplane Maintenance Manual. Or

(ii) Remove the hydraulic motors of the HSA and perform the various follow-on actions specified in paragraph 4.2.2.4 of the AOT, in accordance with that paragraph. (The follow-on actions include checking the motors and the cam seats, assembling the motors, and metal stamping the modification plate of the motors.) If any discrepancy is found during the check, prior to further flight, repair in accordance with paragraph 4.2.2.4 of the AOT.

(b) For airplanes on which any maintenance action relating to a hydraulic motor or a hydraulic valve block of the HSA has occurred since the airplane was new: Within 12 days after the effective date of this AD, accomplish either paragraph (b)(1) or (b)(2) of this AD.

(1) Replace both hydraulic motors of the HSA with new or serviceable motors in accordance with the procedures specified in the Airplane Maintenance Manual. Adjust the synchronization, and perform a functional test of the THS in accordance with paragraph 4.2.2.3 of Airbus AOT 27-21, Revision 1, dated January 5, 1996. Thereafter, perform the repetitive inspections required by paragraph (a) of this AD at intervals not to exceed 500 hours time-in-service. Or

(2) Remove the hydraulic motors of the HSA and perform the various follow-on actions specified in paragraph 4.2.2.4 of the AOT, in accordance with that paragraph of the AOT. Adjust the synchronization, and perform a functional test of the THS in accordance with paragraph 4.2.2.3 of the AOT. (The follow-on actions include checking the motors and the cam seats, assembling the motors, and metal stamping the modification plate of the motors.) If any discrepancy is found during the check, prior to further flight, repair in accordance with paragraph 4.2.2.4 of the AOT. Thereafter, perform the repetitive inspections required by paragraph (a) of this AD at intervals not to exceed500 hours time-in-service.

(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, Standardization Branch, ANM-113, 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, Standardization Branch, ANM-113.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Standardization Branch, ANM-113.

(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.

(e) The actions shall be done in accordance with Airbus All Operators Telex (AOT) 27-21, Revision 1, dated January 5, 1996. 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.

(f) This amendment becomes effective on February 5, 1996, to all persons except those persons to whom it was made immediately effective by telegraphic AD T96-01-52, issued January 9, 1996, which contained the requirements of this amendment.