Airworthiness Directive · Amendment 39-17634 · Flight controls
Airbus Airplanes
This AD applies to Airbus Model A330-301, -302, -303, -321, -322, -323, -341, -342, and -343 airplanes; and Model A340-211, -212, -213, -311, -312, and -313 airplanes; certificated in any category; all manufacturer serial numbers.
We are adopting a new airworthiness directive (AD) for all Airbus Model A330-300 series airplanes and Model A340-200 and -300 series airplanes. This AD was prompted by reports of corrosion found on certain trimmable horizontal stabilizer actuators (THSA), affecting the ballscrew lower splines between the tie bar and the screw-jack. This AD requires repetitive detailed inspections for corrosion of certain THSAs, ballscrew integrity tests if necessary; and replacing any affected THSA with a serviceable or new and improved THSA, if necessary. We are issuing this AD to detect and correct corrosion of the THSAs, which could lead, in the case of ballscrew rupture, to the loss of transmission of THSA torque loads from the ballscrew to the tie-bar, prompting THSA blowback, and possibly resulting in loss of control of the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
At the applicable time specified in paragraph (g)(1) or (g)(2) of this AD, except as required by paragraphs (h)(1) and (h)(2) of this AD: Do a detailed inspection of the gaps between the screw shaft and tie rod teeth of any THSA having part numbers (P/N) 47147-500 and 47147-700, to determine if the corrosion condition is Type I, Type II, or Type III, in accordance with the Accomplishment Instructions of Airbus Mandatory Service Bulletin A330-27-3179, Revision 01, dated June 13, 2013 (for Model A330-301, -302, -303, -321, -322, -323, -341, -342, and -343 airplanes); or A340-27-4175, Revision 01, dated June 13, 2013 (for Model A340-211, -212, -213, -311, -312, and -313 airplanes); and the Accomplishment Instructions and flowchart following the Accomplishment Instructions of Goodrich Actuation Systems Service Bulletin 47147-27-18, dated February 17, 2012. Repeat the inspection thereafter at intervals not to exceed 24 months until the modification specified in paragraph (k) is done.
(1) For any THSA, which, as of the effective date of this AD, has accumulated less than 156 months since its first flight on an airplane as THSA P/N 47147-400, or since its first flight after the modification specified in the Accomplishment Instructions of Airbus Mandatory Service Bulletin A330-27-3052 or A340-27-4059 has been done: Do the inspection before the accumulation of 156 months but not before the accumulation of 132 months since first flight on an airplane as THSA P/N 47147-400, or since the THSA's first flight after the modification specified in the Accomplishment Instructions of Airbus Mandatory Service Bulletin A330-27-3052 or A340-27-4059 has been done; or within 3 months after the effective date of this AD; whichever occurs later.
(2) For any THSA, which, as of the effective date of this AD, has accumulated 156 months or more since its first flight on an airplane as THSA P/N 47147-400, or since its first flight after the modification specified in the Accomplishment Instructions of Airbus Mandatory Service Bulletin A330-27-3052 or A340-27-4059 has been done: Do the inspection within 3 months after the effective date of this AD.
(1) Some THSAs having P/N 47147-500 (and further derivative with P/N 47147-700) were originally THSA P/N 47147-400 and were subsequently modified in service. In this case, the time accumulated by any THSA must be calculated from the first installation on airplanes as THSA P/N 47147-400.
(2) Some THSAs having P/N 47147-500 (and further derivative with P/N 47147-700) were originally THSA P/N 47147-200, -210, -213, -300, -303, or -350 and were subsequently modified in service as specified in the Accomplishment Instructions of Airbus Mandatory Service Bulletin A330-27-3052 or A340-27-4059. In this case, the time accumulated by any THSA must be calculated from the first flight on an airplane after the THSA has been modified as specified in the Accomplishment Instructions of Airbus Mandatory Service Bulletin A330-27-3052 or A340-27-4059.
If, during any inspection required by paragraph (g) of this AD, it is determined that a THSA has Type II or Type III corrosion: Before further flight, do a ballscrew integrity test, in accordance with the Accomplishment Instructions of Airbus Mandatory Service Bulletin A330-27-3179, Revision 01, dated June 13, 2013 (for Model A330-301, -302, -303, -321, -322, -323, -341, -342, and -343 airplanes); or A340-27-4175, Revision 01, dated June 13, 2013 (for Model A340-211, -212, -213, -311, -312, and -313 airplanes).
(1) For THSAs having Type II or Type III corrosion, and on which the results of the ballscrew integrity test were not correct, as specified in the Accomplishment Instructions of Airbus Mandatory Service Bulletin A330-27-3179, Revision 01, dated June 13, 2013 (for Model A330-301, -302, -303, -321, -322, -323, -341, -342, and -343 airplanes); or A340-27-4175, Revision 01, dated June 13, 2013 (for Model A340-211, -212, -213, -311, -312, and -313 airplanes): Before further flight, replace the affected THSA with a new or serviceable THSA, in accordance with the Accomplishment Instructions of Airbus Mandatory Service Bulletin A330-27-3179, Revision 01, dated June 13, 2013 (for Model A330-301, -302, -303, -321, -322, -323, -341, -342, and -343 airplanes); or A340-27-4175, Revision 01, dated June 13, 2013 (for Model A340-211, -212, -213, -311, -312, and -313 airplanes).
(2) For THSAs having Type III corrosion, and on which the results of the ballscrew integrity test are correct, as specified in the Accomplishment Instructions of Airbus Mandatory Service Bulletin A330-27-3179, Revision 01, dated June 13, 2013 (for Model A330-301, -302, -303, -321, -322, -323, -341, -342, and -343 airplanes); or A340-27-4175, Revision 01, dated June 13, 2013 (for Model A340-211, -212, -213, -311, -312, and -313 airplanes): Within 10 days after the most recent inspection, replace the THSA with a new or serviceable THSA, in accordance with the Accomplishment Instructions of Airbus Mandatory Service Bulletin A330-27-3179, Revision 01, dated June 13, 2013 (for Model A330-301, -302, -303, -321, -322, -323, -341, -342, and -343 airplanes); or A340-27-4175, Revision 01, dated June 13, 2013 (for Model A340-211, -212, -213, -311, -312, and -313 airplanes).
(3) For THSAs having Type II corrosion, and on which the results of the ballscrew integrity test are correct: Within 24 months or 4,400 flight cycles after the most recent inspection, whichever occurs first, replace the THSA with a new or serviceable THSA, in accordance with the Accomplishment Instructions of Airbus Mandatory Service Bulletin A330-27-3179, Revision 01, dated June 13, 2013 (for Model A330-301, -302, -303, -321, -322, -323, -341, -342, and -343 airplanes); or A340-27-4175, Revision 01, dated June 13, 2013 (for Model A340-211, -212, -213, -311, -312, and -313 airplanes).
Replacement of a THSA with a THSA having P/N 47147-500 or 47147-700 does not constitute a terminating action for the repetitive inspections required by paragraph (g) of this AD.
(1) Replacing any THSA having P/N 47147-500 with a new improved THSA having P/N 47172-300 (Airbus modification 200238), in accordance with the Accomplishment Instructions of Airbus Service Bulletin A330-27-3182 (for Model A330-301, -302, -303, -321, -322, -323, -341, -342, and -343 airplanes); or A340-27-4178 (for Model A340-211, -212, -213, -311, -312, and -313 airplanes); both dated February 14, 2012; terminates the repetitive inspections required by paragraph (g) of this AD.
(2) Replacing any THSA having P/N 47147-700 with a new improved THSA having P/N 47172-530 (Airbus modification 202802), in accordance with the Accomplishment Instructions of Airbus Service Bulletin A330-27-3194 (for Model A330-301, -302, -303, -321, -322, -323, -341, -342, and -343 airplanes); or A340-27-4187 (for Model A340-211, -212, -213, -311, -312, and -313 airplanes); both dated October 8, 2012; terminates the repetitive inspections required by paragraph (g) of this AD.
As of the effective date of this AD, no person may install a THSA, P/N 47147-500 or P/N 47147-700, on any airplane, unless the THSA is classified as Type I (no corrosion), in accordance with the criteria defined in Goodrich Actuation Systems Service Bulletin 47147-27-18, dated February 17, 2012; and thereafter inspected in accordance with the requirements of paragraph (g) of this AD and any applicable actions required by paragraph (i) of this AD are accomplished.
